Tag Archives: processed food

More than 70% of America’s packaged food is ultra-processed — and it’s a big problem

The food supply in the US is dominated by ultra-processed foods which are almost always high in energy, saturated fat, sugar, and salt.

Avoid ultra-processed foods, physicians warn. Image credits: FDA.

Unhealthy processed food

For every 10 calories someone in the US eats, 8 come from store-bought foods and beverages (packaged and unpackaged). The ready-to-eat food market plays a crucial role in the US, and it also plays a crucial role in the development of obesity and cardiovascular diseases.

Time and time again, studies have shown that processed foods (and particularly, ultra-processed foods) are dangerous to human health. Not only do they make you fat, but they also increase the risk of many serious conditions, including cancer and diabetes — and yet, Americans can’t have enough of them.

“The US packaged food and beverage supply is large, heterogeneous, highly processed, and generally unhealthy,” the new study reads.

Scientists analyzed 230,156 products, finding that 71% of products such as bread, salad dressings, snack foods, sweets, sugary drinks and more were ultra-processed. When they looked at the largest 25 manufacturers, a whopping 86% of products were classified as ultra-processed.

Scientists also ranked foods based on their healthfulness, using a ranking system developed in Australia that ranks foods from 0.5 stars (unhealthiest) to 5 stars (healthiest) The Health Star Rating system scores packaged foods, offering consumers a quick look at the nutritional profile of packaged foods — something which can be difficult to assess in our day to day lives.

What’s ultra-processed anyway?

A decision we’ve all had to make countless times — what did you choose? Image credits: US Air Force.

The way we eat has changed substantially in the past few decades.  When early dietary guidelines were compiled and published in the first half of the last century, the vast majority of foods was sold as ingredients to be combined and consumed in the form of dishes or meals, or eat as it is. But after the 1950s, things started to change. More and more, we had access to pre-packaged, branded, and ready-to-eat (or drink) food. This was seen as more convenient and became increasingly prominent in high-income countries. But not long after that, it became clear that foods purchased this way aren’t healthy at all.

Although processed foods don’t need to be unhealthy, in practice, they almost always are. This is why the NOVA classification for food was devised, to help people understand what’s processed and what’s not. Here are the main categories:

  • unprocessed or minimally processed foods (think seeds, fruits, vegetables, eggs, etc);
  • processed culinary ingredients (flour, butter, vegetable oils, etc);
  • processed foods (relatively simple foods prepared with 2-3 ingredients — think canned beans or sugared nuts);
  • ultra-processed foods (complex foods that typically have many ingredients including sugar, oils, fats, salt, stabilizers, and preservatives — think foods like ice cream, cakes, sodas, burgers, sausages, nuggets, pastries, energy bars, and many many more).

Ultra-processed foods are unhealthy no matter where you look but compared to other countries, the US version is even worse, because it is generally processed with a higher sugar and sodium content, the study reports.

While the study did not analyze 100% of the market, it analyzed data collected by the Chicago company Label Insight, which represents more than 80% of all food and beverage products sold in the US over the past three years — enough to paint a comprehensive picture.

“We need to better capture real-time information of our constantly changing food supply if we’re going to track and improve its healthfulness,” said study co-author Dr. Mark Huffman, the Quentin D. Young Professor of Health Policy, associate professor of preventive medicine and medicine at Feinberg and a Northwestern Medicine cardiologist.

The fact that the average American has an unhealthy diet isn’t really a surprise by now. However, it’s important to understand the scale of the problem and reduce it as much as possible.

“To say that our food supply is highly processed won’t shock anyone, but it’s important that we hold food and beverage manufacturers accountable by continually documenting how they’re doing in terms of providing healthy foods for consumers,” said lead author Abigail Baldridge, a biostatistician in the department of preventive medicine at Northwestern University Feinberg School of Medicine. “And the verdict is they can and should be doing a whole lot better.”

The study was published in the journal Nutrients.


Eating processed food linked to eating too much and being overweight

A new study confirms a long-standing theory of nutrition science: processed food really makes you eat more.

This image shows one of the study’s processed lunches, consisting of quesadillas, refried beans, and diet lemonade. Image credits: Hall et al./Cell Metabolism.

Some researchers have long thought that eating processed food leads to overeating, but separating individual factors like this is hard to do because comparing dietary habits is notoriously complicated. However, in the new study, researchers were able to show that even when two diets were matched for the amount of carbohydrates, fat, sugar, salt, and calories — people consumed more food and gained weight on an ultra-processed diet.

“I was surprised by the findings from this study, because I thought that if we matched the two diets for components like sugars, fat, carbohydrates, protein, and sodium, there wouldn’t be anything magical about the ultra-processed food that would cause people to eat more,” says lead author Kevin Hall, a section chief in the Laboratory of Biological Modeling at the National Institute of Diabetes and Digestive and Kidney Diseases within the National Institutes of Health. “But we found that, in fact, people ate many more calories on the ultra-processed diet, and this caused them to gain weight and body fat.”

The study enrolled 20 healthy (an important limitation of this study is its small sample size). Each participant was given either an ultra-processed diet or an unprocessed diet for two weeks. The meals were then switched. The volunteers were given three meals a day and had access to bottled water and either ultra-processed or unprocessed snacks throughout the day. They were instructed to eat as much as they want.

Meanwhile, researchers measured the quantities of consumed food.

The scale of the difference was shocking: during the two weeks that they were given ultra-processed food, participants consumed an average of 508 calories more per day, compared with the days they got unprocessed food. For reference, an average woman needs to eat about 2000 calories per day to maintain, and an average man needs to eat about 2500 calories.

This image shows one of the study’s unprocessed lunches, consisting of a spinach salad with chicken breast, apple slices, bulgur, sunflower seeds, and grapes. Image credits: Hall et al./Cell Metabolism.

Participants gained, on average, 2 pounds (0.9 kg) during the two weeks of processed food, but lost them in the unprocessed diet weeks. Body fat exhibited a similar trend, growing during the processed food weeks and dropping during for the unprocessed diet.

Researchers also noticed another interesting trend: when people were on the processed diet, they ate faster.

“There may be something about the textural or sensory properties of the food that made them eat more quickly,” Hall also adds. “If you’re eating very quickly, perhaps you’re not giving your gastrointestinal tract enough time to signal to your brain that you’re full. When this happens, you might easily overeat.”

It’s not fully clear why these differences were observed. It could be that, as Hall speculates, the speed of eating is very important. Another hypothesis refers to the role of solid foods versus beverages. In order to match the calorie and dietary fiber intake, researchers had to add lemonades and juices to the ultra-processed meals. These juices were “spiked” with dietary fiber since processed foods tend to be extremely poor in fibers. However, even though the nutritional content was perfectly matched, some researchers believe that beverages don’t offer the same satiety as solid foods. So people might have not felt as full and might have been more inclined to overeat on the processed diets.

A third factor could be that although the diets were matched as closely as possible, the unprocessed diet contained slightly more protein, about 15.6% of calories versus 14% for the ultra-processed diet. “It could be that people ate more because they were trying to reach certain protein targets,” Hall speculates.

Regardless of the reason, this is one of the first studies to directly show that processed food can lead to overeating. Ultra-processed foods have been linked to a multitude of health problems, from gut conditions to cancer. We need to be mindful of what we eat, researchers urge. A healthy diet involves lots of fruits and veggies, low quantities of sugar and processed foods.

“We know there are a lot of factors that contribute to why someone might choose an ultra-processed meal over an unprocessed one,” Hall says. “For people in lower socio-economic brackets especially, we need to be mindful of the skills, equipment, knowledge, and expense needed to create unprocessed meals.”

Journal Reference: Cell Metabolism, Hall et al.: “Ultra-processed diets cause excess calorie intake and weight gain: An inpatient randomized controlled trial of ad libitum food intake”

Strong link found between ultra-processed foods and cancer

Ultra-processed foods, such as pre-made cakes, fizzy drinks, or nuggets, may be associated with a higher risk of cancer, a new study concludes.


Unhealthy processed snacks. Image credits: National Cancer Institute.

Generally speaking, processed foods tend to be bad for you. They’re often sweeter, richer in calories, and lower in healthy nutrients than their counterparts. There’s no strict definition for ultra-processed foods, though they typically involve a large number of additives (such as preservatives, sweeteners, sensory enhancers, flavors and processing aids), but little or no whole foods. A new study has found another reason to avoid these processed foods: they might be linked to cancer.

French researchers at the Université Sorbonne Paris Cité analyzed the diets of around 105,000 people for an average of five years. Participants were split into four equal groups, depending on how much processed foods they had in their diet.

Researchers found a correlation between ultra-processed foods and cancer — the more processed foods people ate, the higher the cancer risk, for all groups. When the proportion of ultra-processed foods increased by 10%, the risk of overall cancer increased by 12%, with the risk of breast cancer alone increasing by 11%. This is particularly worrying since previous studies have found that people are eating more and more processed foods. Americans get 61% of their calories from highly processed foods. Within this study, 18% of the people’s diet was ultra-processed.

Researchers note that the findings need to be replicated in different populations, but they also raise a red flag — if we start eating more and more processed foods, the burden of cancer will likely increase accordingly.

“If confirmed in other populations and settings, these results suggest that the rapidly increasing consumption of ultra-processed foods may drive an increasing burden of cancer in the next decades.”

Overall cancer risk according to quarters of proportion of ultra-processed food in diet. Image credits: Fiolet et al / BMJ.

However, not everyone is convinced by this study. It’s not that anyone’s saying that processed foods are good for you, but there are still a few points of debate. For instance, it’s not exactly clear what an ultra-processed food really is. In this study, researchers defined them as “mass produced packaged breads and buns; sweet or savosamry packaged snacks; industrialised confectionery and desserts; sodas and sweetened drinks; meatballs, poultry and fish nuggets, and other reconstituted meat products.” They also included instant noodles and frozen ready meals in the list. But Tom Sanders, head of the diabetes and nutritional sciences division at King’s College London, says that including “mass-produced” in the definition of ultra-processed foods seems arbitrary and unnecessary.

While on average, mass-produced foods tend to be less healthy, there’s no underlying reason why this is always the case. Conversely, there’s no reason why a small production batch is necessarily healthier. Taking a simple example, let’s say you have two breads — one that was mass produced and sold in the millions, and another that is produced by a local, artisanal bakery. Chemically and nutritionally, they could be the same bread but by the study’s definition, one might be ultra processed and the other might not.

Furthermore, the more pressing issue is that of causality. Essentially, this study has found a correlation, but there’s nothing to suggest that the processed foods themselves are causing the cancer. Even if they are, we don’t really know if they’re causing it directly.

Processed foods are known to affect your body in a number of ways, and that can have cascading effects. For instance, they make you fatter, and being fatter makes you more likely to suffer from cancer. Is there a separate mechanism through which they’re linked to cancer, or is it just because of the extra pounds? That remains to be answered.

Prof Linda Bauld, Cancer Research UK’s prevention expert, said:

“It’s already known that eating a lot of these foods can lead to weight gain, and being overweight or obese can also increase your risk of cancer, so it’s hard to disentangle the effects of diet and weight.”

However, there’s still a clear takeaway. There’s another study in an already impressive pile that says you should be careful not to eat too much processed food.

Journal Reference: Thibault Fiolet et al. Consumption of ultra-processed foods and cancer risk: results from NutriNet-Santé prospective cohorthttps://doi.org/10.1136/bmj.k322

Why processed foods make you fat: two common food additives linked to obesity and gut inflammation

A new study suggests that two very common emulsifiers – chemicals that stabilize foods and stop products like mayo from separating – could increase the risk of obesity and irritable bowel syndrome.

Mayo and mustard are among the products which almost always contain emulsifiers. Image via Wiki Commons.

The emulsifiers in question are carboxymethycellulose and polysorbate-80; especially in Europe and North America, they are commonly used in processed foods (mayo, ketchup, numerous sauces, ice cream, gluten-free products, fat-free products and many others) and other common products (toothpaste, detergents etc). The study conducted on mice showed that even in low concentrations, these substances drastically affect the gut bacteria which seems to lead to obesity as well as a number of gut-related problems.

In recent times, numerous studies have shown that gut bacteria is crucial to our well-being; it’s important to our weight, immune system and digestive health… it may even control our mind (seriously). Anything disrupting the activity of the “good bacteria” in the gut has the potential to do massive damage. With this in mind, the scientists who conducted this new study might have found why processed food make us so fat, and why gut conditions like irritable bowel syndrome have increased since the mid-twentieth century, especially in association with processed foods.

Andrew Gewirtz at Georgia State University and his team added the two emulsifiers in varying levels to the drinking water of lab mice. They found that most healthy mice who were given the emulsifiers soon developed metabolic problems and/or became obese. When they fed mice even more emulsifiers, they started to develop inflammatory gut diseases, with the severity of the affection being directly linked to the quantity of ingested emulsifiers. These effects were seen even in mice that consumed the equivalent of just one-tenth of the concentration of the emulsifiers that the FDA permits in food products.

The researchers then wanted to see why this happens, so they tested the gut bacteria of these animals and found that the emulsifiers destroy much of the microbial fauna in the gut (again, this microbial fauna is actually beneficial to the body).

Scientists advise eating less processed foods. Image via Wiki Commons.

This is extremely worrying because it’s not easy to find emulsifier-free foods – products labeled as ‘organic’ are just as likely to contain these substances, as emulsifiers are not generally considered processed (I’m really not sure why though). Gewirtz says that many more human and animal studies need to be completed before regulatory agencies would consider changing how additives are approved – but it seems clear that we need to change the way we approve and the way we eat, especially when it comes to processed foods.

The next step would be to move on to human tests and see how our bodies are reacting to these substances. Over the past 50 years, no study has conclusively found that food additives are toxic in mammals, but then again, no large studies have ever focused on the gut bacteria.

Overall, this paper adds a lot to the idea that processed foods have long-lasting and hard to understand effects on our bodies – effects which aren’t at all positive.

Immunologist Andrew Gewirtz at Georgia State University in Atlanta who was also involved in the study concluded:

“When it comes to people making their own decisions, between our studies and others out there, it’s better to eat less processed food,” he says.

You can read the full scientific paper for free, at Nature.