Tag Archives: Calorie

Cold sandwiches are calorie traps — don’t fall for it

For some reason, we tend to feel that cold food isn’t as filling as hot food, and it’s tricking us into overeating.

When you’re tempted to conclude that the human species is rational, you may want to slide over to marketing research and check out a journal called Appetite. The journal looks at sensory and other influences on people’s selections of food and drinks. It doesn’t take long to understand the selections we make don’t exactly scream common sense.

A recent research effort in the journal examines our practice of adding orders “on the side” if our main item on order is a cold sandwich. They found that customers who bought cold sandwiches were twice as likely to order a la carte extras such salty crisps and cookies, as if the sandwich, just for its being cold, could not possibly satisfy them without companion sides.

Imagine customer Raph telling the waiter what he wants. After studying his lunch menu, he pats on cold crabmeat sandwich. He wants to know, “What will it come with?” Raph looks at the sides list on the menu and taps on stuffed olives and plantain chips. Was Raph’s sandwich (580 calories and 26 grams of fat, but who’s counting) was not enough to sustain him for a few hours?

If we look at the research in focus, we know that Raph or customers standing at takeout counters think they need more than just the sandwich to complete a sit-down eating experience, because it’s just a cold sandwich, and that’s not much. They simply feel that the cold sandwich alone will not offer ample satiety.

“We show that the temperature at which foods and beverages are served impacts consumers’ complementary purchases, defined as additional foods and beverages purchased for a consumption episode.” wrote Sara Baskentli, Lauren Block, Maureen Morrin in their journal article, “The serving temperature effect: Food temperature, expected satiety, and complementary food purchases.”

Somebody cared

Anyone hunting for explanations for this behavior might remember all the family memories of steaming food on a table marking religious holidays and celebrations. A psychological add-on is that the hot food is a reminder that somebody in the household cared enough to stand, mix, pour, bake, braise, and simmer so that you could be pleased and nourished. Translation: Hot food equals caring. Cold food? Not so much.

To test the hypothesis, researchers examined customers’ café orders over a two-week period. The researchers saw 123 customers’ orders at a New York City café with sandwiches on their menu. People buying cold sandwiches were twice as likely to buy other food items. As for cold beverage orders? Calorie and money traps were evident, too.

“When a customer purchased a cold beverage, they were three times more likely to also buy food items, such as a croissant or a muffin,” said the news release from Rutgers.

The authors in their paper nailed the good news for restaurant business and the caution for the rest of us.

“Serving temperatures that increase complementary purchasing may enhance the firm’s bottom line, but could add unnecessary calories to the meal, and thus is of interest to both consumers and managers.”

In the bigger picture, this is a research discussion that indicates the important difference between appetite and hunger. Scientists like to point out the difference between the two words. Appetite is not hunger, plain and simple. According to the Aspen Clinic, for example, “appetite” involves a “conditioned response to food” and the word is more closely linked to behavior and emotional connection to food. Appetite “can increase/decrease due to hormones, emotional state, and taste preferences.”

Pizza study shows one big meal isn’t as bad for you if your nutrition is healthy overall

Most people would have enjoyed participating in this study by University of Bath researchers — especially because it involves eating a lot of pizza.

Researchers recruited 14 healthy participants and had them eat pizza on two occasions: one time until they were comfortably full, and the other until they couldn’t eat another bite. The results, as the eternal clickbait goes, will surprise you.

Image credits: Chad Montano.

Researchers at the Centre for Nutrition, Exercise and Metabolism at the University of Bath analyzed the blood of participants before and after each meal.

In the ‘eat all you can’ group session, participants ate around 3000 kcal on average, roughly about one and a half large pizzas — about two times more than the other ‘normal meal’ group. However, this varied a lot, as some individuals were able to consume up to two and a half large pizzas in one go. Researchers were surprised to see that even when participants pushed way beyond their usual limits and doubled their calorie intake, they managed to keep the amount of nutrients in the bloodstream within the normal range, at least in the short term.

Essentially, this one overindulgent meal did not seem to make much of a difference, says lead researcher Aaron Hengist.

“We all know the long-term risks of over-indulgence with food when it comes to obesity, type II diabetes and cardiovascular disease, but we know much less about some of the immediate effects ‘all you can eat’ places on the body. Our findings show that the body actually copes remarkably well when faced with a massive and sudden calorie excess. Healthy humans can eat twice as much as ‘full’ and deal effectively with this huge initial energy surplus.”

For instance, blood sugar was no higher than after a normal meal, and blood lipids were only slightly higher. The one major difference was the amount of insulin in the blood, which was 50% higher for the large meal than the normal one.

The study also analyzed the participants’ appetite and found that after eating the big pizza meal, participants felt sleepy, lethargic, and had no desire to eat anything else, even dessert. This was somewhat surprising, researchers note, because reward centers in the brain are typically food-specific, so eating a lot of pizza might not be expected to change the desire for sweet food.

This study should not be interpreted as ‘eat all you want and all is OK’. All the participants in the study had a healthy body mass index and were generally healthy — this was a one-off for them, and it was a very small sample size, insufficient to draw any general conclusions.

Still, given all the interest in nutrition and how people tend to overeat, we know surprisingly little about maximal eating, says Professor James Betts, who oversaw the work.

“We know that people often eat beyond their needs, which is why so many of us struggle to manage our body weight. It is therefore surprising that no previous research had measured the maximal capacity for eating at a single meal in order to understand how the human body responds to that challenge.”

“This study reveals that humans are capable of eating twice as much food as is needed to make us feel ‘full’, but that our bodies are well adapted to an excessive delivery of dietary nutrients at one huge meal. Specifically, those tested in this study were able to efficiently use or store the nutrients they ingested during the pizza-eating challenge, such that the levels of sugar and fats in their blood were not much higher than when they ate half as much food.”

The study could also help reconcile research about how and when we eat. For instance, recent studies have shown that people who eat one big breakfast burn more calories than those who don’t.

While the question of the long-term effects of one-off big meals is still unanswered, it’s encouraging to know that if your diet is healthy overall, one exception probably won’t make a huge difference.

“The main problem with overeating is that it adds more stored energy to our bodies (in the form of fat), which can culminate in obesity if you overeat day after day. However, this study shows that if an otherwise healthy person overindulges occasionally, for example eating a large buffet meal or Christmas lunch, then there are no immediate negative consequences in terms of losing metabolic control.”

The study has been published in the British Journal of Nutrition.

You burn more calories in the afternoon than in the morning

All other things equal, you consume about 10% more calories in the afternoon than in the morning — something which surprised even researchers.

“The fact that doing the same thing at one time of day burned so many more calories than doing the same thing at a different time of day surprised us,” says Kirsi-Marja Zitting of the Division of Sleep and Circadian Disorders at Brigham and Women’s Hospital and Harvard Medical School, lead author of the paper.

A calorie is essentially a measure of energy. Our bodies get energy from food, and that energy can be measured in calories. Although it’s technically unofficial, the calorie is by far the most common measure of food energy, and is a common talking point of most diets and nutritional strategies.

If you’ve ever kept an eye on your calorie intake and consumption, then you probably know what the Resting Metabolic Rate is — essentially, it’s a measure of how many calories the body consumes without doing anything. Think of it this way: you get energy from food, and you burn some of it just by existing; it’s pretty nice.

Zitting and colleagues wanted to see how calorie consumption is affected by the time of day, so they studied seven people in a special laboratory without any clues about what time it was outside. There were no clocks, windows, phones, or Internet. Participants were given fixed hours when they had to go to bed and, to make things even more confusing, those times were adjusted four hours later each night.

“Because they were doing the equivalent of circling the globe every week, their body’s internal clock could not keep up, and so it oscillated at its own pace,” co-author Jeanne Duffy, also in the Division of Sleep and Circadian Disorders at Brigham and Women’s Hospital, explains. “This allowed us to measure metabolic rate at all different biological times of day.”

They found that the circadian rhythm has a strong impact on the resting metabolic rate. During the biological night, when the body cools down slightly, calorie consumption was lowest — which makes a lot of sense. What was unusual, however, was that energy consumption was highest 12 hours later, during the biological afternoon — 10% more than the normal rate. The participants’ respiratory quotient, which reflects macronutrient utilization, also varies by circadian phase, and the two may be connected.

This adds to an already growing number of studies showing that our metabolic rates differ greatly — not only from person to person, but also from time to time.

“It is not only what we eat, but when we eat–and rest–that impacts how much energy we burn or store as fat,” Duffy says. “Regularity of habits such as eating and sleeping is very important to overall health.”

Next, the team will look at how appetite and the body’s response to food vary with time of day.

Journal Reference: Current Biology, Zitting et al.: “Human Resting Energy Expenditure Varies with Circadian Phase” https://www.cell.com/current-biology/fulltext/S0960-9822(18)31334-4

Cutting calories delays ageing, new study shows

A new comprehensive study has shown that reducing caloric intake slows down metabolism. Researchers believe the findings indicate that a low-calorie diet could extend lifespan and prolong health in old age.

Via Pixabay/Divily

Previous studies on animals with short lifespans — such as worms, mice, and flies — have shown that reducing calorie intake might slow down metabolism and prolong life. However, demonstrating this effect on humans and other animals with long lifespans has proven quite difficult.

Researchers studied some of the people who participated in the multi-center trial CALERIE (Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy), sponsored by the US National Institutes of Health. Scientists observed the effects of restricting calories for 2 years on metabolism in over 200 healthy, non-fat adult participants.

“The CALERIE trial has been important in addressing the question of whether the pace of aging can be altered in humans,” says Rozalyn Anderson, who studies aging at the University of Wisconsin–Madison. She leads one of two large, independent studies on calorie restriction in rhesus monkeys. “This new report provides the most robust evidence to date that everything we have learnt in other animals can be applied to ourselves.”

The latest paper, which was published on March 22nd in the journal Cell Metabolism, monitored 53 CALERIE participants recruited at the Pennington Biomedical Research Center in Baton Rouge, Louisiana. Researchers were able to track how the participants used energy with unprecedented precision thanks to state-of-the-art metabolic chambers —  small, hotel-like sealed rooms that measure oxygen and carbon dioxide concentrations every 60 seconds. Researchers calculated the ratio between the two gases and then analyzed occupants’ urinary nitrogen, indicating whether the occupant is burning fat, carbohydrate or protein.

Participants, with ages between 21 and 50, were randomly separated into two groups: the 34 people in the experimental group reduced their calorie consumption by an average of 15%, while the 19 people in the control group ate as usual. Next, researchers tested the participants annually to record overall metabolism and biological markers of aging, including damage associated with oxygen free radicals released during metabolism. At the end of the trial, participants spent 24 hours in the metabolic chamber.

Researchers discovered that the people who had dieted used energy much more efficiently while sleeping than the control group. Their base metabolism had essentially slowed down. In consequence, people in the experimental group lost an average of 9 kilos individually. All other measurements showed a reduced metabolic rate and fewer signs of aging.

“The Rolls-Royce of a human longevity study would carry on for many decades to see if people do actually live longer,” says Pennington physiologist Leanne Redman, the lead author of the latest study.

Low-calorie diets have previously been shown to extend life in different species, such as the short lifespan worm Caenorhabditis elegans, and in the fly Drosophila melanogaster. Following studies also revealed that mice with restricted diets can live up to 65% longer than mice allowed to eat freely. In addition, studies on monkeys suggest longer survival and reduced signs of aging.

Redman wants to repeat the study combining moderate calorie restriction with a diet rich in antioxidants to monitor oxidative stress, or with a drug such as resveratrol, which mimics key aspects of calorie restriction.

If researchers demonstrate the causality between caloric reduction and longer lives in humans, could you stick to such a diet?

Reconstruction of the mid-Pliocene Protarctos abstrusus in the Beaver Pond site area during the late summer. Credit: Art by Mauricio Antón.

Scientists find primitive 3.5-million-year old bear with a sweet tooth for berries

Reconstruction of the mid-Pliocene Protarctos abstrusus in the Beaver Pond site area during the late summer. Credit: Art by Mauricio Antón.

Reconstruction of the mid-Pliocene Protarctos abstrusus in the Beaver Pond site area during the late summer. Credit: Art by Mauricio Antón.

Two 3.5-million-year-old bears had a sweet tooth for berries. Paleontologists have discovered ancient teeth with cavities that serve as evidence.

“This is evidence of the most northerly record for primitive bears, and provides an idea of what the ancestor of modern bears may have looked like,” says Dr. Xiaoming Wang, lead author of the study and Head of Vertebrate Paleontology at the Natural History Museum of Los Angeles County (NHMLA).

“Just as interesting is the presence of dental caries, showing that oral infections have a long evolutionary history in the animals, which can tell us about their sugary diet, presumably from berries. This is the first and earliest documented occurrence of high-calorie diet in basal bears, likely related to fat storage in preparation for the harsh Arctic winters.”

A rare glimpse into High Arctic life

The international team of researchers excavated the ancient bear fossils belonging to Protarctos abstrusus at the Beaver Pond site on Ellesmere Island, Canada. This site is one of the few where fossils have been found in the Arctic, especially mammal fossils.

Unlike other sites down south where scientists can chisel fossils out of rock, at Beaver Pond you have to pick your way through layers of peat. The bones are usually fragmented from all the repeated cycles of freezing and thawing, and appear brown or iridescent blue in color due to the presence of a mineral called vivianite.

The first pieces of a bears skulls’ were found in the 1990s. During excavations over the last 14 years, paleontologists have recovered more fragments of the skull, a jaw, and other skeleton fragments. When the researchers pieced together the fragments, they found the pieces belonged to two bears. One was five to seven years old and the other was older. Both didn’t seem to brush their teeth, judging from the cavities.

“It is a significant find, in part because all other ancient fossil ursine bears, and even some modern bear species like the sloth bear and sun bear, are associated with lower-latitude, milder habitats,” says co-author Dr. Natalia Rybczynski, a Research Associate and paleontologist with the Canadian Museum of Nature. “So, the Ellesmere bear is important because it suggests that the capacity to exploit the harshest, most northern forests on the planet is not an innovation of modern grizzlies and black bears, but may have characterized the ursine lineage from its beginning.”

Digital reconstruction of the Canadian Arctic fossil bear, Protarctos abstrusus. Credit: Xiaoming Wang.

Digital reconstruction of the Canadian Arctic fossil bear, Protarctos abstrusus. Credit: Xiaoming Wang.


Along with the fossils, scientists have found remains of raspberry, blueberry, lingonberry and crowberry plants. Their sweet berries likely helped the ancient bears hibernate through the polar winter, just like their modern cousins.

While Canada’s High Arctic doesn’t look all that hospitable nowadays, three and a half million years ago Beaver Pond was home to a boreal forest. It provided a home to a variety of animals like beavers, deer, and three-toed horses, to name a few.

A view of the Beaver Pond fossil site, with a number of the animals and plants based on fossils recovered from the site. Credit: George "Rinaldinho" Teichmann.

A view of the Beaver Pond fossil site, with a number of the animals and plants based on fossils recovered from the site. Credit: George “Rinaldinho” Teichmann.

In addition to being able to discern what some ancient bears had for breakfast — which is fascinating in its own right — scientists say the fossils also provide a missing link between primitive and modern bears. The findings suggest that bears were stuffing up on a high-sugar diet to hibernate very early in their evolutionary history. About 44 percent of modern black bears have cavities, which are very rare in other animals.

Protarctos abstrusus — a species first discovered in Idaho in 1970 — was able to reach up to 100 kilograms, making it a bit smaller than modern black bears. The two species are related but Protarctos abstrusus is not the direct ancestor of the black bear, which crossed into North America from Asia much later, during the last ice age.

Scientific reference: Xiaoming Wang et al, A basal ursine bear (Protarctos abstrusus) from the Pliocene High Arctic reveals Eurasian affinities and a diet rich in fermentable sugars, Scientific Reports (2017). DOI: 10.1038/s41598-017-17657-8.

Low calorie diet ensures longer and healthier lifespan for monkeys

Researchers just added more weight to the idea that a low-calorie diet extends lifespan.

A 2009 image of rhesus monkeys in a landmark study of the benefits of caloric restriction. The then 27-year-old monkey on the left was given a diet with fewer calories while the then 29-year-old monkey on the right was allowed to eat as much as it liked.
Credit: Jeff Miller/University of Wisconsin-Madison

As it so often happens, competing teams would have much better results if they worked together instead of trying to surpass each other. This time, a team from the University of Wisconsin-Madison and one from the National Institute on Aging (NIA) have worked together for the first time, leading them to settle a long-standing controversy.

In 2009, the UW-Madison study team found that a low-calorie diet caused significant health improvements, including reductions in cancer, cardiovascular disease, and insulin resistance. Monkeys that ate less than their peers were healthier and lived longer. But then, in 2012, the NIA team reported no significant improvement in survival, but did find a trend toward improved health.

“These conflicting outcomes had cast a shadow of doubt on the translatability of the caloric-restriction paradigm as a means to understand aging and what creates age-related disease vulnerability,” says UW-Madison Associate Professor of Medicine Rozalyn Anderson one of the report’s corresponding authors.

But when they stopped contradicting each other and worked together, they not only realized what the low-calorie diet was doing, but why they were seeing such different results.

The first difference was that the two teams restricted the diets of the monkeys starting at different ages. Analysis has shown that eating less is beneficial in adult and older primates but is not beneficial for younger animals. This is a bit counterintuitive, especially when we consider that in rodents it’s exactly the opposite. Secondly, in the old-onset group of monkeys at NIA, the control monkeys ate less than the Wisconsin control group. Even small differences could lead to broadly different results. Thirdly, the two teams had completely different monkey diets. At the end of the day, it’s not just about the calories but also about the types of foods the monkeys were eating. The NIA monkeys ate organic food while most animals from the Wisconsin National Primate Research Center ate processed foods rich in sugar.

When all these things are controlled for, the improvements in health were clearly visible. Researchers also made another observation: male and female monkeys are affected by calories in different ways. For males, the calorie intensity of the meals was much more important than for females.

At this point, it’s not clear exactly how this translates to humans, but with this type of study, results likely translate as well. In other words, there’s a good chance that reducing the number of calories in your diet could lead you to live a longer and healthier life. This is a landmark finding which could serve as inspiration to countless people all around the planet.

Journal Reference: Julie A. Mattison, Ricki J. Colman, T. Mark Beasley, David B. Allison, Joseph W. Kemnitz, George S. Roth, Donald K. Ingram, Richard Weindruch, Rafael de Cabo, Rozalyn M. Anderson. Caloric restriction improves health and survival of rhesus monkeys. Nature Communications, 2017; 8: 14063 DOI: 10.1038/ncomms14063


The cake isn’t a lie — but the nutritional value on the box definitely is

Food packaging does influence the amount of calories consumed, a new study found. By showing portion sizes much larger than recommended, the pictures on various product’s packaging could make it difficult to eat healthy. Extras such as toppings or frosting on cakes are also usually not taken into account on nutritional labels, exacerbating the problem.

“Layer cake with chocolate bits. Layers filled with icing and cheesecake bits. Iced and topped with caramel sauce & cookies.”
Image credits to flickr user Ginny.

Dr. John Brand and his colleagues at the Cornell University Food and Brand Lab found that the way cakes are depicted on ready-mix cake packaging — in large servings covered with lots of frosting — cause consumers to overestimate portion sizes.

“If we see a slice of cake smothered in frosting on the cake box, we think that is what is normal to serve and eat,” he explained in a statement.

“But that’s not what is reflected in the serving size recommendation on the nutrition label,”

This can lead people to overestimate what constitutes an ordinary, healthy serving of the high-calorie desert, he and his colleagues found.

The team carried out a series of four studies to find out if images on food packaging can influence serving size. They used 51 different cake mixes to see if people would overestimate how much calories each contained by looking at the picture alone. This would in turn cause them to serve larger portions.

In the first study, they compared the cake’s caloric value as listed on the nutritional label with the actual number calories contained in the cake and frosting as shown on the package. The results showed that the products usually had 134 percent more calories than the label stated.

So for the final three studies, the team recruited undergrads or food-service professionals and gave each of them one typical cake mix box. Some were informed that the nutritional label doesn’t factor in the frosting, but most of them weren’t. They were then asked to asses whether or not the depicted piece of cake was a reasonable serving.

Undergrads that were warned about the nutritional labels’ inaccuracy wanted smaller portions than their peers. The final study found that even industry professionals would, on average, over-serve cake without that information.

“Undoubtedly, companies don’t intend to deceive us when they include frosting in cake box depictions, but these seemingly small elements of packaging can have a huge impact,” explained co-author Dr. Brian Wansink, director of the Food and Brand Lab.

Simply including a warning that frosting or other extras are not included in nutritional labeling would make packaging “less misleading,” the study concludes.