Tag Archives: obesity

Credit: Pixabay.

Sleeping too little is bad for your health, but so is too much

Getting less than six hours of shut-eye per day is associated with metabolic syndrome, which can lead to weight gain, raised blood pressure, insulin resistance, and inflammation among other things. However, sleeping for too long, such as more than ten hours per day, can also trigger metabolic syndrome.

Credit: Pixabay.

Credit: Pixabay.

There is still a lot we don’t know about the role of sleep and what exactly goes inside the brain during slumber. But while its functions haven’t been fully mapped out, scientists agree that quality sleep is critical to a healthy lifestyle. For instance, previous studies have found that neurons are remodeled during sleep and that animals and humans deprived of sleep do not perform well on memory tasks. According to National Heart, Lung and Blood Institute, prolonged sleep deficiency is also linked to an increased risk of heart disease, kidney disease, high blood pressure, diabetes, and stroke.

A new study performed by researchers at the Seoul National University College of Medicine adds new depth to the importance of sleep in human health. The team crunched the numbers on a huge dataset from the HEXA study, a large-scale community-based study conducted in Korea during the years 2004-2013, involving 133,608 Korean men and women aged 40 to 69 years. For each HEXA participant samples of plasma, serum, buffy coat, blood cells, genomic DNA, and urine were collected. Sleep duration was assessed by asking the question: “In the past year, on average, how many hours/minutes of sleep (including daytime naps) did you take per day?”

The authors found that nearly 11% of men and 13% of women slept less than six hours each day, while 1.5% of men and 1.7% of women slept more than ten hours.

Compared to individuals who slept six to seven hours per day, men who slept fewer than six hours were likelier to have metabolic syndrome and a higher waist circumference. Women who slept less than six hours were more likely to have a higher waist circumference.

Metabolic syndrome is a cluster of conditions — increased blood pressure, high blood sugar, excess body fat around the waist, and abnormal cholesterol or triglyceride levels — that occur together, increasing your risk of heart disease, stroke, and diabetes.

Both men and women who slept for more than ten hours a day were at a higher risk of developing metabolic syndrome and increased levels of triglycerides than people who slept under ten hours. Additionally, women who slept more than ten hours per day also showed signs of high blood sugar and low levels of ‘good’ cholesterol (HDL-C).

“This is the largest study examining a dose-response association between sleep duration and metabolic syndrome and its components separately for men and women. Because we were able to expand the sample of our previous study, we were able to detect associations between sleep and metabolic syndrome that were unnoticed before. We observed a potential gender difference between sleep duration and metabolic syndrome, with an association between metabolic syndrome and long sleep in women and metabolic syndrome and short sleep in men,” said Claire E. Kim, lead author of the new study published in the journal BMC Public Health. 

The prevalence of metabolic syndrome was just over 29% in men and 24.5% in women. However, the biological mechanisms that underlie the association between sleep duration and metabolic syndrome are not clear yet. One possible explanation is that elevated levels of hormones increase appetite and caloric intake or reduce energy expenditure in people who are sleep deprived.

Whatever may be the case, this is yet another study that underscores the importance of sleep for living a healthy life.

Illustration of the new pill developed at BWH that mimics the effects of gastric bypass surgery. Credit: Brigham and Women's Hospital and Randal Mckenzie.

“Surgery in a pill” mimics weight loss benefits of gastric band or bypass surgery

Researchers at the Harvard Medical School have developed an oral treatment that delivers the same weight-loss benefits associated with invasive procedures such as gastric band or bypass surgery.

Illustration of the new pill developed at BWH that mimics the effects of gastric bypass surgery. Credit: Brigham and Women's Hospital and Randal Mckenzie.

Illustration of the new pill developed at BWH that mimics the effects of gastric bypass surgery. Credit: Brigham and Women’s Hospital and Randal Mckenzie.

The pill is essentially a gut-coating medication that prevents sugars and other nutrients in food from being absorbed by the intestines. Taken before each meal, this treatment ought to offer the same benefits of bariatric weight-loss surgery with lower risk and at a lower cost. In a couple of hours, the effects of the pill dissipate.

When coupled with exercise and a healthy diet, weight loss surgery has been found effective in dramatically reducing a patient’s excess body fat.

Gastric band surgery involves inserting a band that reduces the stomach’s size, meaning you will feel full after eating a reduced amount of food. Recent research in the United States found that people with gastric bands lose around half of their excess body weight. Meanwhile, gastric bypasses reduce this excess body weight by two-thirds post-op. The surgery involves re-routing the digestive system past the stomach, so you digest less food and it takes less to make you feel full.

Besides weight loss, gastric bypass — one of the best-studied surgeries in the world — can also lead to other beneficial health outcomes, including positive effects for blood pressure, sleep apnea, and certain forms of cancer. The surgery is also remarkably effective at curing type 2 diabetes.

Having a pill that mimics the effects of this kind of surgery without all the hassle involved with a gastric bypass would be immensely valuable to patients and healthcare providers.

“We envision a pill that a patient can take before a meal that transiently coats the gut to replicate the effects of surgery,” said co-senior author Jeff Karp, PhD, a bioengineer and principal investigator at Brigham and Women’s Hospital (BWH). “Over the last several years, we’ve been working with our surgical colleagues on this idea and have developed a material that meets an important clinical need.”

According to the researchers at BWH at Harvard, the transient coating has so far only been tested on rats. Experiments showed that the rodents’ blood sugar levels were 47 percent lower than in rats without the treatment. This shows that calories weren’t taken up although the rats ate the same diets.

“What we’ve developed here is essentially, ‘surgery in a pill,'” said co-lead author Yuhan Lee, PhD, a materials scientist in the BWH Division of Engineering in Medicine. “We’ve used a bioengineering approach to formulate a pill that has good adhesion properties and can attach nicely to the gut in a preclinical model. And after a couple of hours, its effects dissipate.”

The pill’s main component is sucralfate, a substance that is already approved as safe for human consumption in treating ulcers of the stomach and intestine. Since the main active ingredient is already FDA-approved, the enrolling process for a clinical trial should run more smoothly, although it’s not clear at this point if the pill is safe for human consumption or — if it is safe — how long before it might become available.

The findings appeared in the journal Nature Materials.

Weight gain is mostly controlled by what you eat — not genetics

If you want to blame someone for those extra pounds, the best place to look is probably in the mirror.

As the world tries to deal with its ever-growing obesity crisis, the main causes of this problem are still under debate. However, more and more studies are indicating that the main culprit is, as expected, food.

Genes decide a lot of things about your body — your eye color, your hair, even how you look like. But, according to a new study, it doesn’t really decide how much you weigh (as an adult, at least). Scientists at King’s College London recently carried out a study on twins to assess how the gut processes and distributes fat.

Essentially, they analyzed poop samples from over 500 pairs of twins to build up a picture of how the gut microbiome distributes fat. They also analyzed how much of this process is genetic and how much is directed by environmental factors. Overall, they found that only 17.9% of all gut processes could be attributed to hereditary factors, while 67.7% of gut activity was influenced by environmental factors — mainly, the regular diet.

This is an exciting study, not just because it confirms that what we eat governs how our weight is distributed, but because it allows researchers to understand which microbes are associated with which chemical metabolites in the gut. Ultimately, this could help scientists understand how the gut bacteria affects us, and how it can be modified for weight management.

The fecal metabolome largely reflects gut microbial composition, and it is strongly associated with visceral-fat mass, thereby illustrating potential mechanisms underlying the well-established microbial influence on abdominal obesity. Dr. Jonas Zierer, the lead author of the study, believes this could one day be instrumental in dealing with obesity.

‘This study has really accelerated our understanding of the interplay between what we eat, the way it is processed in the gut and the development of fat in the body, but also immunity and inflammation. By analysing the faecal metabolome, we have been able to get a snapshot of both the health of the body and the complex processes taking place in the gut.’

This is also good news because it means that most of the factors associated with extra pounds are modifiable. Zierer adds:

‘This new knowledge means we can alter the gut environment and confront the challenge of obesity from a new angle that is related to modifiable factors such as diet and the microbes in the gut. This is exciting, because unlike our genes and our innate risk to develop fat around the belly, the gut microbes can be modified with probiotics, with drugs or with high fibre diets.’

Head of the Department of Twin Research at King’s, Professor Tim Spector was also excited by the possibility. He emphasizes another advantage of this study — the fact that potential treatments or supplements might be implemented at a large scale through innovative approaches.

‘This exciting work in our twins shows the importance to our health and weight of the thousands of chemicals that gut microbes produce in response to food. Knowing that they are largely controlled by what we eat rather than our genes is great news, and opens up many ways to use food as medicine. In the future these chemicals could even be used in smart toilets or as smart toilet paper.’

Worldwide, over 2 billion people are overweight or obese, and over the past 20 years, obesity rates have more than doubled. The growing trend shows no sign of stopping or slowing down, as childhood obesity also grows at dramatic rates: 1000% in the past 40 years.

Journal Reference: Zierer et al. “The fecal metabolome as a functional readout of the gut microbiome.” Nature Genetics (2018). https://doi.org/10.1038/s41588-018-0135-7

Over 4% of English children are obese by the time they’re 11

More than 1 in 25 children in England are severely obese by the time they leave primary school. The overall number of children entering primary school obese is 15,000 — and by the time they finish primary, there will be 22,000 of them.

This is not the ideal children’s food.

Obesity is definitely a modern plague. For the first time in its history, mankind has (in the developed world, at least) an abundance of nutrients and foods available at its disposal. The problem, it seems, is that we’re largely incapable of choosing wisely. Right now, mankind is facing an obesity pandemic, with 2 billion individuals worldwide. Childhood obesity has also grown by a staggering amount: 1000% in the past 40 years. In Europe, Britain is the most obese country, whereas worldwide, the US is the undisputed “champion” of obesity rates, with 70.1% of its population being overweight, and 38.2% obese.

In England, it’s the first time this type of comprehensive analysis has been carried out on childhood obesity. The Local Government Association (LGA), which published the report based on Public Health England figures, said more government action was urgently needed. Izzi Seccombe, chairwoman of the LGA’s community wellbeing board, said:

“These new figures on severely obese children, who are in the most critical overweight category, are a further worrying wake-up call for urgent joined-up action.” She added that unless the problem is tackled, “today’s obese children will become tomorrow’s obese adults” .

However, the government seems unimpressed by these figures. The UK leaders insist that their plan to tackle obesity is among the most comprehensive in the world, even though things seem to be getting worse.

Truth be told though, the UK government isn’t just idling. Just a month ago, it implemented a tax on sugary drinks, which was hailed by doctors and policymakers alike as a victory for health. Already, in many bars across the country, the diet version of soft drinks has become prevalent (and while this is still far from ideal, it’s a big step forward). But for all its merits, the sugary tax might not be enough — and, more importantly, the growth of obesity might be connected with other, deeper problems.

The widely controversial austerity measures implemented over the past decade have caused poverty in the UK to soar. NY Times’ Peter Goodman recently wrote, “After eight years of budget cutting, Britain is looking less like the rest of Europe and more like the United States, with a shrinking welfare state and spreading poverty” — and this is clearly visible in the obesity rates. Unfortunately, healthy food is often more expensive than the unhealthy, calorie-rich alternatives. As a result, Britain has developed its own fast-food culture, with pre-packaged and pre-cooked food often being the norm. These foods are generally cheaper, more filling, but also very unhealthy.

Obesity is linked to a swarm of health problems including type 2 diabetes, high blood pressure, gallstones, asthma, liver disease, kidney disease, and several types of cancer.

high calorie food

An energy-dense diet changes the brain — makes rats hungrier and more prone to obesity

It’s no secret that consuming energy-dense foods consistently promotes weight gain. However, when Stephanie Borgland at the University of Calgary gave rats unrestricted access to high-fat, high-sugar foods, the rodents not only got fat, their brains changed too. The food essentially rewired their brains, inducing the rodents to crave more of the same food, even when their hunger should have been satisfied.

high calorie food

Credit: Pixabay.

Borgland and colleagues fed rats a the so-called “cafeteria diet”, which, besides the regular “rat chow” (a balanced diet), consists of unlimited access to food rich in fat and sugar, such as chocolate and other treats. Freely left to eat any food and as much as they wished from the 24h/day cafeteria diet, the rats became obese in only 40 days. However, rats that had limited access to the energy-dense diet (one hour per day), did not become obese.

“Eating an energy dense diet can change circuits in your brain to make you want to eat more. This is not food addiction, but probably a natural mechanism to help you maximize opportunities to eat when presented with energy dense (typically palatable) food,” Borgland told ZME Science.

Previously, work carried out by the same team of researchers had shown that obese mice have modifications in signaling in a brain region called the orbitofrontal cortex (OFC), which is located right above the orbits of the eyes. This brain region is associated with decision-making and receives information from the senses in order to register the value of the food, then updates feeding behavior based on this information. For instance, delicious-smelling food relayed to the OFC by the sense of smell might promote a more enthusiastic appetite.

In non-obese animals, satiety leads to food devaluation, which reduces appetite. Conversely, obese animals show a reduction in the inhibitory signals on a class of neurons called pyramidal neurons, found in the OFC. In other words, the obese rats feel less full even though they should be.

The new study identified endocannabinoid signaling as a key component in this modification, which was a very exciting discovery.

“Obesity is typically associated with an elevated level of endocannabinoids in both humans and rodents, so these results are not surprising,” Borgland said in a statement. “However, endocannabinoid signaling is much more complex than previously thought. Our research shows that endocannabinoid signaling selectively affects inhibitory signals onto the pyramidal neurons of the OFC. This effect is mediated through changes in specific receptors on the neurons, but may also involve other types of cells in the brain, called astrocytes,” the researcher added.

Since 1975, obesity rates around the world have tripled, today leading 13% of the adult population to be classed as obese. Obesity is a serious concern because it is associated with poorer mental health outcomes, reduced quality of life, and the leading causes of death in the U.S. and worldwide including diabetes, heart disease, stroke, and some types of cancer.

“Future studies will need to further investigate the mechanisms through which endocannabinoids affect the motivation to eat beyond satiety. This will be critical in identifying novel therapeutic strategies for treating obesity with fewer side effects” concludes Dr. Borgland.

The findings were presented at the 12th Annual Canadian Neuroscience Meeting. 

A fat belly is bad for your heart

Belly fat, even in people who are not overall overweight, is a sign of an unhealthy heart, a new study reports.

“See your doctor if your waist is bigger than your hips,” said study author Dr. Jose Medina-Inojosa

A fat belly is a bad sign for your health.

The most common way to measure how overweight or underweight someone is the Body Mass Index (BMI), a simple measure defined as the body mass divided by the square of the body height. BMI is a decent index, but it’s far from perfect and can be misleading. BMI completely disregards the distribution of muscle and fat. Muscles are much denser and compact than fatty tissue, so someone with a lot of muscle might seem overweight and similarly, a person might have a normal BMI but be high on fat and low on muscle. Storing fat around the belly is a very bad sign for your health, even if your overall weight seems fine.

The study tracked 1,692 residents of Olmsted County, Minnesota, aged 45 years or older, a sample that was representative of the county population for age and sex. Participants underwent clinical evaluation and also underwent measurements of their weight, height, hip, and waist circumference. Researchers defined central obesity, in a ratio which divides the waist circumference by the hip circumference, as 0.90 or above for men and 0.85 or above for women.

The initial study was carried out from 1997 to 2000, and follow-up evaluations were carried up until 2016. Researchers found that people with a normal BMI and central obesity were twice as likely to suffer from heart problems compared to participants without central obesity, regardless of their BMI. Dr. Medina-Inojosa said:

“People with a normal weight but a fat belly have more chance of heart problems than people without a fat belly, even if they are obese according to BMI. This body shape indicates a sedentary lifestyle, low muscle mass, and eating too many refined carbohydrates.”

The opposite is also true: people with a higher BMI but no belly fat probably have more muscle tissue, which is a sign of better health.

“The belly is usually the first place we deposit fat, so people classified as overweight BMI but without a fat belly probably have more muscle which is good for health,” he continued. “Muscle is like a metabolic storehouse and helps decrease lipid and sugar levels in the blood.”

The main takeaway, Medina-Inojosa says, is for doctors not to assume that patients are at low risk of heart conditions just because they have a normal BMI. As useful as the BMI can be, it can also be misleading, tricking patients into a sense of false security.

“Our study provides evidence that doctors should also measure central obesity to get a better picture of whether a patient is at risk,” Medina-Inojosa concludes.

The results have not been peer-reviewed yet.

The soda tax works: After tax, Philadelphians are 40 percent less likely to drink soda every day

After a soda tax was introduced in Philadelphia, people started drinking less sugary drinks and more water.

The world is facing an unprecedented obesity crisis and sugar is one of the main culprits. We simply eat too much sugar, and not only in its raw form — there’s plenty of sugar embedded in our foods, and especially in our drinks. The consumption of sugary drinks has increased dramatically in the past few decades, and lawmakers are finally stepping in.

In Philadelphia, for instance, a sugar tax was imposed about a year ago. Now, the effects are becoming clear.

The 1.5 cents-an-ounce tax went into effect Jan. 1, 2017, and raised $72.3 million in its first 11 months. That money went into funding pre-K and community schools, and already, there are more children attending these programs. But these are just the secondary aspects of the tax. Its main purpose was to push people to drink less soda — and that’s working too.

A survey of 900 people from Philadelphia found that 40% less likely to drink sugary soda and 60% less likely to drink an energy drink each day. At the same time, they are 58% more likely to drink more bottled water. Yichen Zhong, a doctoral student at the Dornsife School of Public Health and lead author, comments:

“If distributors fully pass the tax on to customers, it could increase the price of soda and energy drinks by about 20 percent,” said Zhong. “It is expected that a price increase of that magnitude will influence some consumers to stop purchasing non-essential items like sugary soda and possibly switch to a lower-priced beverage, like bottled water — and our results are in line with that.”

Interestingly though, not all sugary beverages dropped — the fruit flavors of Snapple and Sunny Delight, for instance, were not seen to have a decline in consumption, and it’s not yet clear why. It may be that people are willing to pay more for them, or that they mistakenly view them as healthier.

“We were not able to assess whether this was because retailers didn’t raise prices for fruit drinks or whether consumers chose to pay more for those beverages. Those drinks may be viewed as healthier than soda despite having the same amount of added sugar (about 10 packets of sugar per 12-ounces),” said Amy Auchincloss, co-author of the study.

The study is important because essentially, it shows that the sugar tax works. There is a mountain of evidence connecting sugar consumption with obesity and diabetes, as well as heart disease and tooth decay.

“Considering that 30 percent of Philadelphians have at least one sugary beverage each day, any kind of cut in consumption could be impactful,” notes Auchincloss.

Recently, the UK has also introduced a nationwide sugar tax for drinks. I’m curious to see whether effects will be similar there as well.

Scientists find link between obesity and body temperature

Scientists have found a potential connection between your ability to maintain your body’s temperature and obesity. But don’t go blaming obesity for those extra pounds just yet.

Screenshot of a video recording of IR thermography of a WT (left) and a TRPM8-deficient mouse (KO, right). Note the difference in the tails of the two mice. Image credits: Reimúndez et al., JNeurosci (2018).

As humans are warm-blooded animals, our bodies work vigorously, day and night, to keep our body temperature constant — and food plays an important role in that process. We don’t often think about it this way, but food is essentially fuel for our body. However, food does much more than just provide us with the energy to operate through the day.

A normal body temperature is around 37 degrees Celsius (99 Fahrenheit), though it may vary somewhat from person to person. Eating tends to lead to a slight increase in body temperature as your metabolic rate increases to allow the digestion of food. Depending on what and how much you eat, your body temperature may increase by as much as 1.1 degrees Celsius (2 Fahrenheit), as the chemical reactions associated with digestion kick in.

Rosa Señarís and colleagues from the University of Santiago de Compostela and the Institute of Neuroscience/University Miguel Hernandez of Alicante (Spain), analyzed a different connection between temperature and food intake. They studied a group of lab mice, disabling their a receptor called TRPM8, also known as the cold and menthol receptor 1 (CMR1). They found that in a mildly cold environment, mice lacking the cold-sensing TRPM8 consumed more food during the day, when mice are usually asleep. This change took place from a young age, and led to obesity and high blood sugar in adulthood. Researchers believe this may have been caused by reduced fat utilization.

This isn’t the first time something like this has been reported. In 2011, a team writing in The American Journal of Clinical Nutrition found that a “lower core body temperature set point has been suggested to be a factor that could potentially predispose humans to develop obesity.” In a 2015 study, researchers found that a “biological inability to create sufficient core body heat could be linked to the obesity epidemic,” concluding that a diurnal thermogenic handicap can play a crucial role in favoring weight gain in obese subjects. Both studies called for more research on the matter, but there seems to be growing evidence for this obesity-temperature connection.

The article ‘Deletion of the cold thermoreceptor TRPM8 increases heat loss and food intake leading to reduced body temperature and obesity in mice’ has been published in JNeurosci. DOI: https://doi.org/10.1523/JNEUROSCI.3002-17.2018

overweight-obesity

Scientists debunk ‘obesity paradox.’ No, you won’t live longer being overweight

overweight-obesity

Credit: CRISPR.

Studies published over the last couple of years had oddly suggested that people who have been diagnosed with cardiovascular disease can expect to live longer if they are overweight or obese. This contradictory association has been called the “obesity paradox.”

It’s well established that being overweight or obese — defined as having a body-mass index (BMI) over 25 — is linked to health risks like cardiovascular disease, osteoarthritis, diabetes, and cancer, to name a few. But what of this so-called obesity paradox? How can we explain it? Well, a new study published in the journal Jama Cardiology suggests there’s not much to debate — we’ve misinterpreted the data all along.

That’s according to researchers at Northwestern University. Dr. Sadiya Khan, an assistant professor of medicine at Northwestern University Feinberg School of Medicine, along with colleagues, examined individual-level data pertaining to over 190,000 in-person examinations. At the time of enrollment, all participants were free of cardiovascular disease. This proved to be critical to debunking the “obesity paradox.”

There isn’t any paradox at all. People of unhealthy weight live unhealthily.

“Recent data have suggested that individuals with cardiovascular disease who are obese may live longer. But, we were able to investigate this in the greater context of healthspan and cardiovascular morbidity and shed light on this controversy by using a lifespan perspective beginning prior to the onset of cardiovascular disease. We are able to provide clear perspective of increased cardiovascular burden in overweight and obese,” Khan told ZME Science.

The data was sourced from 10 large prospective cohorts with an aggregate of 3.2 million years of follow-up. Over follow-up, researchers assessed whether or not participants had acquired any cardiovascular disease, including coronary heart disease, stroke, and heart failure. The researchers also recorded whether fatalities were due to cardiovascular or non-cardiovascular reasons.

This thorough examination shows that there’s a similar longevity between people who are of normal weight and overweight. However, overweight and obese individuals had a much higher risk of developing cardiovascular disease and spent more years with cardiovascular disease than those of normal weight.

Overall, overweight and obese individuals had higher odds of developing a stroke, having a heart attack or heart failure, or dying from heart disease than people of normal weight. Key findings from the study include:

  • The likelihood of having a stroke, heart attack, heart failure or cardiovascular death in overweight middle-aged men 40 to 59 years old was 21 percent higher than in normal weight men. The odds were 32 percent higher in overweight women than normal weight women.
  • The likelihood of having a stroke, heart attack, heart failure or cardiovascular death in obese middle-aged men 40 to 59 years old was 67 percent higher than in normal weight men. The odds were 85 percent higher in obese women than normal weight women.
  • Normal weight middle-aged men also lived 1.9 years longer than obese men and six years longer than morbidly obese. Normal weight men had similar longevity to overweight men.
  • Normal weight middle-aged women lived 1.4 years longer than overweight women, 3.4 years longer than obese women and six years longer than morbidly obese women.

This is the first study to provide a lifespan perspective on the risks of developing cardiovascular disease for normal weight, overweight, and obese individuals. Its findings are greatly welcomed seeing how the obesity paradox has seeded confusion and may even have caused harm. Suddenly, people would wonder why they should go through the effort of losing weight when research showed they are going to live longer. We now know this isn’t the case. What’s more, losing weight doesn’t only reduce the incidence of cardiovascular disease, but also other afflictions like diabetes or cancer.

“Future research needs to focus on strategies for primordial prevention to reduce the burden of cardiovascular disease in the population as a whole. We are also interested in identifying the differences in healthcare costs related to cardiovascular morbidity and mortality associated with overweight and obese,” Khan said.

At the end of the day, people should always strive to hover at a normal weight. Even if the obesity paradox were true — and it isn’t — what good is it living a bit longer in an unhealthy body?

“Maintaining a healthy or normal BMI throughout younger to older adulthood is associated with a longer, healthier life!” Khan told our readers.

Scientific reference: Sadiya S. Khan, Hongyan Ning, John T. Wilkins, Norrina Allen, Mercedes Carnethon, Jarett D. Berry, Ranya N. Sweis, Donald M. Lloyd-Jones. Association of Body Mass Index With Lifetime Risk of Cardiovascular Disease and Compression of MorbidityJAMA Cardiology, 2018; DOI: 10.1001/jamacardio.2018.0022.

pan pot

How your waterproof jacket might be making you fat

pan pot

Credit: Pexels.

Chemical compounds used in the manufacturing of non-stick pots and pans, stain-resistant clothing and carpets, and food packaging might be putting people at risk of becoming obese. A new study found an association between chemicals called perfluoroalkyl substances (PFASs) and high levels of obesity, which scientists hypothesize could be disrupting the body’s ability to burn calories properly.

The team at Harvard University led by Qi Sun, an associate professor at the university’s Department of Nutrition, analyzed the records for 621 overweight and obese individuals who were followed for two years as they dieted.

Over the first six months of the trial, participants had lost 6.4 kg, but somewhat expectedly regained 2.7 kg over the course of the following 18 months. What was surprising, however, was that those who gained the most weight back also had the highest blood concentrations of PFASs, and this was particularly true for women.

According to the study published in the journal PLOS Medicine, women with the highest PFAS levels gained about 2 kg more than those with the lowest levels of PFASs. Upon closer investigation, the researchers found that those with PFAS levels in their blood also burned calories slower, having a lower resting metabolic rate.

The scientists were quite fortunate to complete their investigation: the diet trials were conducted in the 2000s, and along the years the samples had been drained for other research.

“When this project was funded, plasma samples collected from study participants in the POUNDS-Lost trial were almost depleted because they were used for other projects over the years. These precise samples have to be shared among trial investigators. One of the most memorable and happiest moments was when Dr. Jeremy Furtado (our lab director) finally found enough samples in freezers!” Sun told ZME Science in an email.

PFASs have been employed in the manufacturing of a wide range of products in the last 60 years from food wrapping to pots to clothing. These are very persistent chemicals that, once in the bloodstream, stay there and accumulate, potentially causing chronic illnesses. Highly fluorinated chemicals have been previously associated with kidney and testicular cancer, elevated cholesterol, decreased fertility, thyroid problems, and hormone disruption.

The new findings now suggest that PFASs are also obesogenic — chemicals that promote excess weight gain and obesity. PFASs may be acting on a pathway that slows down the metabolism, though more research is needed to investigate this relationship, as this cannot be determined from a causal study.

“Given this is the first human study that linked PFASs with weight regain after dieting, I would like to call for replications and further research for mechanisms. Having said this, I think the public should be aware of the issue of PFASs exposures and associated potential health consequences,” Sun told ZME Science.

“I personally avoid using products that contain PFASs whenever possible. For example, I primarily use cast iron instead of nonstick cookware to cook dinner and do not eat fast foods, including popcorn, that can be contaminated by PFASs through contact with food packaging materials,” he advises.

junk food

Junk food could be taxed like cigarettes or alcohol, researchers find

junk food

Credit: Pixabay.

Researchers found that a tax on junk food is both legally and administratively feasible at the federal level in the United States. Proponents of such a tax claim it will help curb obesity in the country which is now peaking at alarming levels, essentially becoming a public health hazard.

“Economic and social environments can influence food choice in beneficial and harmful directions. Our finding that a federal manufacturer excise junk food tax — defined through product category or combined category-nutrient approaches — appears to be legally and administratively feasible and has strong implications for nutrition policy,” said Jennifer L. Pomeranz,  who is an assistant professor of public health policy and management at NYU College of Global Public Health.

According to the CDC, 36.5 percent of American adults and roughly 20 percent of children ages 6 to 19 are obese. What’s more, over 70 percent of all men and 60 percent of all women from the US are overweight. This makes a huge fraction of the country’s population at risk of developing cardiovascular disease, cancer, diabetes, osteoarthritis, and chronic kidney disease. And to be fair, this is no longer an American problem. A third of the world’s population —  over two billion people — is now either overweight or obese.

Given the public health risks, many experts believe we ought to enact policies that improve American diets. One course of action would be to regulate the price of food and beverage to incite consumers to make healthier choices, either through taxing unhealthy foods or offering subsidies for healthier foods.

A legally feasible tax

Researchers at New York University and the Friedman School at Tufts University investigated the feasibility of implementing a national soda or junk food tax. A federal-level tax, rather than state-by-state, is preferred because the effects are broader and you avoid seeing things like consumers traveling from state to state to fill groceries and dine at restaurants where they can escape the tax. On the other hand, the United States is not heterogeneous in its citizens’ attitude towards junk food or healthy eating, which will make a nation-wide tax challenging to implement.

The team examined the present scientific literature to identify which products should be targeted for junk food taxes but also looked elsewhere where similar legislation was passed. There are eight countries in the world who have implemented some kind of food and beverage taxation specifically aimed at curbing obesity.

Kerala, a state on India’s tropical Malabar Coast, imposed a 14.5 percent tax on the consumption of fast food. In 2014, France introduced a tax on sugary drinks that made a noticeable dent in the sales. And in the United States, some municipalities have taken matters into their hands. The city of Berkeley, for instance, introduced a one penny-per-ounce tax on all sugar-sweetened beverages sold in the city. Five months after its implementation, lower-income residents had reduced their consumption of these items by 21 percent compared to pre-tax levels.

Researchers identified four ways of classifying foods:

  • by product category (such as soda or candy),
  • broad nutrient criteria,
  • specific nutrients or calories,
  • or a combination.

The most frequently targeted categories were sugar-sweetened beverages, candy, processed meat products, and sweet and salty snacks, and the most frequently targeted foods were sugar, calories, and salt.

Next, the researchers looked at the various federal taxing mechanisms that would be the most administratively feasible. For instance, there are two main types of tax: sales or excise. Excise taxes are charged on the manufacture, distribution, or sale of commodities, and it’s up to the taxed entity to determine the extent to which it will pass on the tax to consumers. Sales taxes are paid directly by consumers and collected by sellers.

Other countries where there’s a junk food tax overwhelmingly use an excise tax mechanism, similar to the kind you see for alcohol and tobacco.

“One advantage of a manufacturer excise tax is that food companies may be incentivized to reformulate their products if nutrition criteria are incorporated into the tax,” Pomeranz said.

Ultimately, from a legal and administrative perspective, the team concluded that a federal junk food tax is feasible. Existing bills and laws support defining junk food through product-specific categories, and add a graduated taxation strategy where the tax increases as the nutritional quality of the food decreases. From an administrative perspective, current taxing mechanisms support the viability of a junk food excise tax paid by manufacturers, the researchers reported in the American Journal of Public Health. So, the ball is now in the court of policymakers who have the, admittedly, challenging and unpopular job of taxing junk food and soda.

 

Intensive weight management can put type 2 diabetes into remission

After the intensive program, patients lost 10 kg (22 pounds) on average and half of them reverted to a non-diabetic state without any diabetes treatment whatsoever.

Image credits: Tero Vesalainen.

Type 2 diabetes is a chronic, lifelong condition where the body doesn’t produce enough insulin or the cells stop responding to insulin, leading blood sugar to rise to dangerously high levels. Almost 90% percent of the people suffering from it are overweight or obese, and there’s a very tight connection between extra pounds and diabetes. Worldwide, type 2 diabetes incidence has quadrupled, rising from 108 million in 1980 to 422 million in 2014 and showing no sign of stopping. The world is eating unhealthily and it’s paying the price for it. Heavy medication can keep the disease under control, but Scottish researchers had a different idea: if the problem lies in the diet, the solution might also be there. So they implemented an aggressive diet to 298 adults aged 20-65 years who had been diagnosed with type 2 diabetes. Results were encouraging to say the least.

“Our findings suggest that even if you have had type 2 diabetes for 6 years, putting the disease into remission is feasible”, says Professor Michael Lean from the University of Glasgow who co-led the study. “In contrast to other approaches, we focus on the need for long-term maintenance of weight loss through diet and exercise and encourage flexibility to optimise individual results.”

Rather surprisingly, diet and lifestyle are rarely discussed as a treatment for diabetes. Even when they are discussed, the focus is more on what you should and shouldn’t eat, not on how much you should eat. The root cause, unfortunately, is often ignored.

“Rather than addressing the root cause, management guidelines for type 2 diabetes focus on reducing blood sugar levels through drug treatments. Diet and lifestyle are touched upon but diabetes remission by cutting calories is rarely discussed”, explains Professor Roy Taylor from Newcastle University, UK, who co-led the study.

So researchers started by changing the diet of the patients. It wasn’t a simple diet to follow, as they were only allowed to consume 825-853 calories/day for 3 to 5 months — for comparison, sedentary men and women burn around 2,400 and 2,000 calories per day, respectively. After a period, patients were gradually reintroduced to a normal diet. They were also offered support for weight loss maintenance, including cognitive behavioral therapy combined with strategies to increase physical activity. For this entire period, all diabetes and blood pressure-lowering drops were completely stopped.

Image credits: Blue Diamond Gallery.

Interestingly, the program was considered acceptable by most participants. Dropout rate was 21%, but it was mostly caused by social reasons (i.e. moving to a different city or starting a new job). The results were truly impressive.

The average weight loss was 10 kg, but a quarter of participants dropped 15 kg (about 33 pounds) or more. The remission rate was also tightly connected to the weight loss rate. For instance, half of all participants were diabetes-free by the end of the study, but 9 out of 10 participants who lost 15 kg or more went into remission. Researchers note that the patients were white and British, so the same findings may or may not carry on to other types of people.

Even so, the results are truly encouraging, and there is a good chance they do pass on to other populations. The fact that simply losing weight (which also reduces your risk of cancer, cardiovascular diseases, and many other health issues) gives people a great chance of getting rid of diabetes, should give many people hope. Now, all we need to do is convince people to lose weight and not gain it back. Professor Taylor concludes:

“Our findings suggest that the very large weight losses targeted by bariatric surgery are not essential to reverse the underlying processes which cause type 2 diabetes. The weight loss goals provided by this programme are achievable for many people. The big challenge is long-term avoidance of weight re-gain. Follow-up of DiRECT will continue for 4 years and reveal whether weight loss and remission is achievable in the long-term.”

The study was published in The Lancet.

Being overweight is even more harmful than we thought, new study shows

We knew that extra pounds are bad for your health, but a new study claims that we may have underestimated the effect.

From left to right, a healthy, overweight, and obese man. Image credits: Report of the Dietary Guidelines Advisory Committee on the Dietary Guidelines for Americans.

The reason, researchers say, is that the early stages of illness (when weight is often measured) associated with a higher risk of mortality are also associated with a lower body mass index (BMI). In other words, when you’re really sick, you might lose some extra pounds, and that might skew the data.

In order to reach this conclusion, Bristol researchers analyzed the (BMI),  along with health and mortality data for around 60,000 parents and their children — 30,000 mother and child pairs and 30,000 father and child pairs were assessed. The idea was to analyze them in such a way that eliminates “reverse causation” — disease causing lower BMI, not BMI causing disease.

So researchers wanted to see what would happen if instead of correlating the parent’s health with his own BMI, they correlated it with the child’s BMI. When they did this instead of conventional analysis, the harmful effects of high BMI were greater than those found in the conventional analyses.

Dr David Carslake, the study’s lead author and Senior Research Associate from the MRC Integrative Epidemiology Unit (IEU) at the University of Bristol, said:

“An alarming increase in obesity levels across the world which have risen from 105 million in 1975 to 641 million in 2014, according to a recent Lancet study, create concern about the implications for public health.”

Still the current recommended BMI range hasn’t changed. The BMI, which is defined as the body mass divided by the square of the body height, is recommended to be under 25.

“This study demonstrates that correlation is not causation and that when it comes to public health recommendations we need to be cautious interpreting data based on associations alone. We found that previous studies have underestimated the impact of being overweight on mortality and our findings support current advice to maintain a BMI of between 18.5 and 25.”

Whether or not the effects of being overweight have been underestimated or not remains a matter of debate, but it’s clear that without establishing causation, observational studies (even large-scale studies), can include large errors and significantly skew our perspective.

Journal Reference: ‘Confounding by ill health in the observed association between BMI and mortality: Evidence from the HUNT Study using offspring BMI as an instrument’ by David Carslake et al in International Journal of Epidemiology, 26.10.2017

Britain becomes Europe’s most obese country, as US maintains “leader” status worldwide

Britain’s obesity rates have almost doubled in only 20 years, with rates increasing faster than any other developed nation. Over 60 percent of the country is now obese or overweight.

Image credits: OECD.

The world is dealing with an obesity crisis that shows no sign of stopping down. Obesity is touching people of all ages, ethnicities, and either gender. A new report from Organization for Economic Cooperation and Development (OECD) found that within OECD countries, 54% of people are fatter than they should be, with 19.4% being obese.

The most overweight country is Mexico, where over 72% of people are overweight and 33.3% are obese. The US has fewer overweight people, at “only” 70.1%, but has the most obese people in the world: 38.2%.

The case of UK is particularly concerning as the rates grow at an alarming rate. However, the rates of Korea and Norway have also doubled since 1990, though total figures aren’t as high as in Britain. However, Britan’s overall health indicators remain strong. Life expectancy is 81 years, largely due to access to low-cost, quality healthcare, thanks to the country’s National Health Service (NHS). The UK per capita health expenditure is more than two times lower than that of the US.

The OECD reports that access to care is generally good, though the NHS is under great financial stress in recent years.

“The average access to care is generally good. Out of pocket payments are low, and few people report skipping consultations due to the cost of care — 4.2 percent compared to an average of 10.5 percent among 17 OECD countries with comparable data,” the report says.

The health problems associated with obesity are severe and far-reaching, the report highlights. Obesity increases the likelihood of various diseases and conditions, particularly cardiovascular diseases, type 2 diabetes, obstructive sleep apnea, certain types of cancer, osteoarthritis, and depression, significantly reducing life expectancy.

While most countries in the developed world have various campaigns against obesity, their efficiency has proven to be relatively low. It’s not that they don’t have an impact, but they don’t do enough to counteract rising obesity rates, and much more could be done, the report writes. For instance, England’s decision to ban ‘super-size’ chocolate bars from hospital outlets is laudable but will do little to curb the overall problem. The impending government sugar tax is expected to have a much more significant impact, though it remains to be seen exactly how effective the tax will be in tackling overall obesity rates.

Obesity is most commonly caused by a combination of excessive food intake and lack of physical activity, through genetic predispositions can also play a role. The good news is that obesity is completely preventable and treatable, through a series of fairly simple lifestyle changes. Improvements in overall diet and exercising are the main treatments. Reducing the consumption of foods with high-calorie intake such as sugars and increasing the intake of dietary fiber is the best way to start. Sometimes, medical treatments are also used, but no matter what, nothing can ever substitute healthy eating and exercising.

stressed frog

Stress could be as harmful to your gut’s health as junk food

A study on mice performed by researchers at Brigham Young University (BYU) found stress can be as bad for digestion as a diet of low-nutrient fast food.

stressed frog

Credit: Pixabay.

 

The team studied the gut microbiota of these mice. These bacteria live in a relationship that is vital to normal health, although some species are also opportunistic pathogens that can invade the host gut and cause disease. The human body is host to around 100 trillion microbes, meaning they outnumber somatic cells by about 10 to 1.  

Microorganisms start colonizing the gut immediately after birth in mammalian hosts and are followed by a succession of populations until a stable adult microbiota has been established.

Studies on the microbiota, though numerous, can be extremely challenging. Because there are so many different species of microorganisms colonizing the gut, it can be very difficult if not impossible to identify which organisms are beneficial and which are bad for our health, especially since the effects are rooted in an interplay of various bacteria. Most gut bacteria can’t be cultured in a dish, making these types of studies even harder. What we do know for sure is that the microbiota is essential to the health of all mammals.

Sometimes, the intestine-wandering bacteria can affect us in unexpected ways. For instance, when a team at BYU sampled the gut microbiome from female mice subjected to a stress test, the microbiota resembled that of an obese mouse. This surprising finding seems to suggest that stress can have as much of an impact on our metabolism as poor diet. Interestingly enough, male mice didn’t exhibit the same microbiome shift, but they became more anxious and less physically active.

“Stress can be harmful in a lot of ways but this research is novel in that it ties stress to female-specific changes in the gut microbiota,” BYU professor of microbiology and molecular biology Laura Bridgewater said in a statement. “We sometimes think of stress as a purely psychological phenomenon but it causes distinct physical changes.”

These findings, which were reported in a paper in Scientific Reports, logically follow previous findings. For instance, scientists previously found that high levels of the stress hormone cortisol are linked to a higher body mass index (BMI). The higher the BMI, the more likely an individual is overweight or obese.

This sort of metabolic response to stress, though a nuisance to our modern lifestyle, may have provided evolutionary advantages. When faced with a threat, like a predator, glucose levels rise so we have more energy for our ‘flight or fight’ response. However, when glucose rises, so does insulin, which causes fat storage.

As such, these findings suggest that any diet or weight loss routine should also be paired with stress management. Obese people looking to lose weight are advised to relax more often by engaging in calming and pleasurable activities.

“In society, women tend to have higher rates of depression and anxiety, which are linked to stress,” Bridgewater said. “This study suggests that a possible source of the gender discrepancy may be the different ways gut microbiota responds to stress in males versus females.”

Obesity in U.S. reaches all-time high. Almost half of all Americans are obese, according to latest figures

Almost half of all Americans are obese and there seems to be no stopping this trend, new research shows.

Data from the National Health and Nutrition Examination Survey found that in 2015-2016, 39.8% adults and 18.5% of youth in the US were obese. While extremely worrying, this isn’t really surprising. In the past 30 years, obesity rates have been constantly on the rise, especially among adults. In more recent years, youth obesity has also taken a foothold. From 2000 to 2016, there has been a 30% increase in adult obesity and 33% increase in youth obesity. If this keeps up, then there will soon be more obese than non-obese people.

The main culprits are fairly easy to point out: unhealthy diet and a lack of physical activity. Sugary foods — and just as importantly, sugary drinks — greatly contribute to the surge in obesity prevalence. But there’s no silver bullet to fighting obesity. Changes to diet and exercising are the main “treatments” but they take a lot of time, effort, and motivation. Diet quality can be improved by replacing processed and energy-dense foods (high in fat and sugar) with more fruits and vegetables. Exercise is also extremely important but the sedentary lifestyle is slowly taking over.

That a healthy diet and exercising tackle obesity is not really groundbreaking science. Everyone knows, or at the very least, should know this. But something is not working, it’s not just clicking together. Dr. Craig Hales, medical epidemiologist at the US Centers for Disease Control and Prevention, and author of the study suggests that national policy has been lacking. He is one of the many medical scientists calling for stronger policy and regulation. Michael W. Long, assistant professor at the Milken Institute of School Public Health at George Washington University, who wasn’t involved in the study, says the government just isn’t doing enough. Patrick T. Bradshaw, who studies population health at UC Berkeley, also says we need more aggressive intervention.

However, this growing consensus isn’t being echoed by policymakers. With no clear solutions in sight, a group of nationally disparaged efforts can’t stem the tide of surging obesity rates, especially as the current administration hasn’t made solving the crisis one of its priorities.

The impact of obesity cannot be overstated. Obesity is claiming the lives of some 400,000 Americans every year, costing society an estimated $117 billion in direct and indirect costs. Obesity is one of the main reasons why the US has a relatively low life expectancy compared to other high-income countries.

Childhood obesity has grown by 1,000% worldwide in the last 40 years

In 2016, the number of obese children and teenagers rose to 124 million. Another 213 million children were overweight, a worrying new study shows.

Childhood obesity can lead to life-threatening conditions including diabetes, high blood pressure, heart disease, sleep problems, cancer, and other disorders. Credits: Tony Alter.

The most obese children (above 30%) were in some islands in Polynesia, with the US trailing close by. At a 20% child obesity rate, the US hosts the most obese children in the world. Several Arab countries (eg Egypt, Kuwait, Qatar and Saudi Arabia) also had similar rates. Overall, global obesity prevalence has increased to 5.6% for girls, and to 7.8% for boys, based on the Body Mass Index (BMI).

“Rates of child and adolescent obesity have increased significantly over the past four decades in most countries in the world,” says study author Dr James Bentham, University of Kent, UK. “While average BMI among children and adolescents has recently plateaued in Europe and North America, this is not an excuse for complacency as more than 1 in 5 young people in the USA and 1 in 10 in the UK are obese. Additionally, rates of child and adolescent obesity are accelerating in east, south and southeast Asia, and continue to increase in other low and middle-income regions.

 

The world will have more obese children and adolescents than underweight by 2022, according to a the study by Imperial College London and WHO.

The study, led by Imperial College London in the UK and the World Health Organisation (WHO), gathered data from 2,416 studies involving 128.9 million participants worldwide. Researchers warn that despite massive alarm flags coming from scientists and physicians, governments and policymakers have been slow to react and we are now seeing the effects of this lack of action. Most importantly, we have to change dietary habits — shift away from processed foods and sodas, and focus more on fruits and veggies — through market mechanisms such as taxation. Basically, researchers are indirectly calling for taxing sugar and other unhealthy foods. They say that current policies are especially harmful to people in developing countries and the underprivileged. Unhealthy foods are often cheaper than healthier alternatives, and that’s a problem.

Professor Majid Ezzati, study author from Imperial College London, explains:

“While there have been some initiatives led by governments, communities or schools to increase awareness about childhood and adolescent obesity, most high income countries have been reluctant to use taxes and industry regulations to change eating and drinking behaviours to tackle child obesity. Most importantly, very few policies and programmes attempt to make healthy foods such as whole grains and fresh fruits and vegetables affordable to poor families. Unaffordability of healthy food options to the poor can lead to social inequalities in obesity, and limit how much we can reduce its burden.”

The health issues associated with childhood obesity are complex and far-reaching. The first problems for these obese children are usually emotional or psychological. Bullying and depression go hand in hand with childhood obesity. In the long run, things are even worse, as the children are more likely to develop life-threatening conditions including diabetes, high blood pressure, heart disease, sleep problems, cancer, and other disorders.

To make things even more worrying, the study also found that globally, more children and adolescents remain underweight than obese. The prevalence of moderate and severe underweight has somewhat decreased (from 9.2% to 8.4%), but food security is still a pressing issue in many parts of the world. Almost two-thirds of all underweight children live in South Asia, where 20.3% of girls and 28.6% of boys were moderately or severely underweight in 2016.

Furthermore, these children aren’t at opposite ends of the spectrum — data shows that underweight children can quickly become overweight, due to the same reasons mentioned above. Foods that are poor in nutrients but high in calories tend to be cheaper than healthier alternatives, leading kids to become both obese and malnourished.

The data is pretty much stating what we already knew, but now we get to see the exact magnitude of the problem. Hopefully, faced with the evidence, political figures will take more serious action. By now, this is a worldwide health crisis which should not be treated lightly.

The study was published in the Lancet.

Knee arthritis has doubled since 1950, and we don’t really know why

Aging and obesity alone cannot explain it.

 

Arthritis is an inflammation of the joints (or another area where the bones come together). It’s often a chronic condition which typically starts off in the hands or feet, and most often ends up affecting the knees. It’s estimated that one in five Americans over 45 suffer from knee arthritis, and similar figures are reported in many parts of the world.

Initially, this was thought to be a consequence of aging — people lived to older ages, and therefore started suffering more from “old age diseases.” Obesity is also thought to play a role — the more you weigh, the more pressure you put on your joints. But a new study found that these factors alone cannot explain the rise in knee arthritis prevalence.

Stretching my knees

Image credits: BruceBlaus.

Ian Wallace is a paleoanthropologist at Harvard University who studies how human health and diseases have changed over time. He was aware that knee arthritis is often associated with obesity and aging, but wanted to see how these and other factors affected the prevalence of obesity through the years. So he and his colleagues studied several thousand American skeletons, from pre-industrial, early industrial, and post-industrial periods. They were specifically looking at the wear and tear in the skeleton’s knees. The age and body mass index were also assessed and through statistical processing, the impact of obesity and age was removed.

Wallace and colleagues found that 18 percent of the skeletons from the post-industrial ages (1950) had signs of advanced arthritis, compared to six and eight percent of the early industrial and prehistoric bones, respectively. The statistical model showed that neither aging nor obesity can explain the phenomenon.

“It points to this mysterious conclusion: A lot of cases of osteoarthritis, which we thought might be inevitable, may be preventable… and are due to unknown factors,” Wallace says.

Of course, both obesity and aging take their toll — no one’s saying they just don’t matter. But what this study shows is that there’s something else we’re missing.

What could it be?

The study didn’t attempt to explain the findings, but it’s not very difficult to speculate. Wallace too says that lack of physical activity is a very likely culprit. Since the 1950s, office jobs have multiplied dramatically, more and more cars flood the streets, and physical activity has declined accordingly. Sitting down is also a possible culprit. David Felson, study co-author, a renowned arthritis expert and physician at Boston University comments:

“Our joints don’t do well when they aren’t active much of the time,” Felson says.

But that might not tell the whole story. Inflammation might also be at blame. Arthritis itself is an inflammation, but different inflammations, while a natural reaction, promote injury and prevent proper healing. Francis Berenbaum, a researcher and physician at Pierre and Marie Curie University and  AP-HP hospital in Paris, France, who wasn’t involved in the study, believes an unhealthy diet might also be at blame. The same diet (high in processed foods and sugars) that’s favoring diabetes and heart diseases might also be contributing to arthritis. Other factors, such as walking more on hard surfaces such as concrete or asphalt or concrete might also contribute, but at the moment, the truth is we don’t really know.

“I study this, and I don’t know… what [more] can be done to prevent it,” Felson adds.

For now, your best bet is to keep a healthy diet and be physically active.

Journal Reference: Ian J. Wallace, Steven Worthington, David T. Felson, Robert D. Jurmain, Kimberly T. Wren, Heli Maijanen, Robert J. Woods, and Daniel E. Lieberman — Knee osteoarthritis has doubled in prevalence since the mid-20th century. doi: 10.1073/pnas.1703856114

Overweight Asian Americans seen as “more American” than their thinner counterparts

An unusual study suggests that body weight affects how American someone is perceived as.

Researchers from University of Washington asked more than 1,000 college students to look at photos of Asian, black Latino and white men and women. The photos had been previously edited to create thinner and heavier versions of each subject. All other image variables remained unchanged. They then asked the participants questions such as ‘how likely is this person to have been born outside the U.S.’? and ‘how likely is it that this person’s native language is English’?

The idea was to study what it is that people associate with the image of “American-ness.” Caitlin Handron, a doctoral student at Stanford University and corresponding author, explains:

‘In the U.S., there is a strong bias associating American identity with whiteness, and this can have negative consequences for people of color in the U.S. We wanted to see whether ideas of nationality are malleable and how body shape factors into these judgments.’

White and Black people were seen are more likely to be Americans, which is not really surprising. But rather ironically, people who appeared to be heavier were perceived to be more American than their thinner counterparts — something which did not carry on to participants of different descents. A second analysis showed that overweight Asian men were also perceived as less likely to be in the United States without documentation than their normal-weight counterparts.

Sapna Cheryan, a co-author of the study, discussed how being overweight, a factor that commonly leads to stigmatization, actually provides a racial buffer.

‘We found that there was a paradoxical social benefit for Asian Americans, where extra weight allows them to be seen as more American and less likely to face prejudice directed at those assumed to be foreign.’

So does this mean that there’s something about being heavy that makes people look “more American” — not really. Remember, this only carried out for Asian Americans, not for whites or blacks. However, there might be some truth to this stereotype.

The United States contains one of the highest percentage of obese people in the world, with every two out of three Americans being overweight or obese. This is not only unhealthy but also very costly. It’s estimated that approximately $147 billion is spent on obesity-related medical expenses per year within the United States.

Image credits: Caitlin Handron et al — Unexpected Gains: Being Overweight Buffers Asian Americans From Prejudice Against Foreigners.

It’s not just humans — 1 in 3 US pets are also overweight

A new worrying report found that over a third of all US pets are too plump.

Exercise can do wonders for plump pets, doctors recommend.

The study analyzed data from 2.5 million dogs and 500,000 cats in the United States, taken from 975 veterinary hospitals run by Banfield, a chain that operates in 42 states. According to a standard veterinary check, a third of them weighed more than they should. It’s worth noting that Banfield’s numbers are actually lower than other commonly cited figures from the Association for Pet Obesity Prevention (APOP). According to APOP, over half of all American pets could lose some weight.

This is a trend that’s getting more and more prevalent with every passing year. Banfield says it tracked a 158 percent increase in overweight dogs over the past 10 years, and an even more impressive 169 percent increase in cats. It’s not exactly clear why this is happening, though there are several reasonable causes that contribute.

For starters, now more than ever, pets are being considered part of the family, and as a result, they’re being spoiled. Treats, extra food, scraps — dogs especially enjoy a lot of special treatment. The idea of a normal pet body is also switching. Many pet owners don’t understand that their pet is overweight, which is why they don’t worry and don’t do anything about it. The genetic effects of breeding might also be at play. Just last year, researchers identified a variation in a gene in Labrador retrievers which causes them to often overeat. A similar gene might be present in many other breeds, though this hasn’t yet been established. Breeds might actually be causing numerous long-term problems, as this video (not related to the report) illustrates.

There’s also widespread confusion among owners regarding food. What food should you give your pet? Different doctors recommend different things, the advertising for products is all the same, so what do you do? There’s no universal solution, different animals might require different nutritional inputs, but this might be a problem of quantity rather than quality.

The solution, as is the case with humans, is simple in essence but difficult to apply: diet and exercise. Sure, feeding your pet healthy food is essential, and your vet would surely be able to recommend one of many existing solutions, but too much of anything will make animals overweight. For dogs, there’s a simple way to do that: walk them more. You’ll reap the benefits alongside your dog, and you’ll both be healthier. Apartment cats can also benefit from exercise. Laser pointers, toys, or simple hands-on play can make a big difference. Even just ten minutes every day can have long-term positive impacts, researchers say. To add a bit of motivation, this will also save you money in the long run — healthy pets require less medication and fewer medical procedures, which often cost a lot of money. But the main motivation, of course, should be the well-being of your furry friends.

Researchers highlighted another interesting aspect, for which they have no explanation yet. They were expecting a correlation between human and pet obesity rates, but that wasn’t the case. In fact, in some cases, there was a strong inverse correlation. Louisiana, Alabama, and Mississippi — which have some of the nation’s highest rates of human obesity, according to the Centers for Disease Control and Prevention — all rank in the bottom five states for pet obesity.

These are the states with the most overweight dogs:

  1. Minnesota
  2. Nebraska
  3. Michigan
  4. Idaho
  5. Nevada
  6. New Mexico
  7. Washington
  8. Utah
  9. Indiana
  10. Oregon

These are the states with the most overweight cats:

  1. Minnesota
  2. Nebraska
  3. Iowa
  4. Idaho
  5. Delaware
  6. Michigan
  7. Nevada
  8. Kansas
  9. Utah
  10. New Mexico