How Ultra-processed Foods Drive Obesity, Metabolic Risks

• A new study finds that higher ultra-processed food (UPF) intake is associated with an increased body mass index (BMI).
• The link between UPFs and higher BMI was most pronounced for soda consumption.
• The findings also demonstrate how adherence to the Mediterranean diet may impact BMI.
• The study is relatively small but builds on existing evidence showing the health dangers of consuming ultra-processed foods.

Although ultra-processed food (UPF) is a relatively new term, it has already become a household name. Every new study makes it clearer that many of these products are harmful to human health.

The latest in a long line of studies shows that people who consume more UPFs are more likely to have a higher BMI and increased adiposity — the amount of excess fat an individual has.

The Italian study, recently published in the journal Nutrients, also shows that people who follow the Mediterranean diet the least closely are more likely to have a higher BMI.

For this study, researchers recruited 175 people with obesity, all of whom completed a food diary, providing information about their UPF intake and how closely they followed the Mediterranean diet. The scientists also measured their body composition and BMI.

According to their analysis: “The data showed an increase in UPF consumption as the BMI increased.”

In other words, individuals who consumed the highest amounts of UPFs were more likely to have a higher BMI. At the same time, as UPF intake increased, adherence to the Mediterranean diet decreased.

The scientists found that some UPFs were more closely linked to BMI and adiposity than others, notably soda. This is not the first time soda has been singled out.

Although the recent study is relatively small, it is yet more evidence that reducing UPF intake — particularly soda — is probably a smart move for health.

“The study confirmed what we emphasize to our weight loss patients: Focus on adding lean proteins and vegetables to the diet,” Mir Ali, MD, a board certified general surgeon, bariatric surgeon, and medical director of MemorialCare Surgical Weight Loss Center at Orange Coast Medical Center in Fountain Valley, CA, told Healthline.

“The more processed the food,” he continued, “the more it stimulates insulin secretion and fat deposition.”

Ali noted that “processed foods take less energy to break down and make the person feel hungry sooner.” He also told us that highly processed foods can trigger addictive eating behaviors. “For all these reasons, limiting UPFs can greatly help a person in their weight loss efforts,” he said.

According to NOVA, the most commonly used classification system for food processing, UPFs are:

“Industrially manufactured food products made up of several ingredients (formulations) including sugar, oils, fats, and salt (generally in combination and in higher amounts than in processed foods) and food substances of no or rare culinary use (such as high-fructose corn syrup, hydrogenated oils, modified starches, and protein isolates).”

This means UPFs tend to contain large quantities of sugar, fat, and a list of ingredients you would not find in a standard home kitchen. UPFs are produced industrially, are relatively low cost, and have a long shelf life, all of which make them convenient for the customer and the manufacturer. Importantly, they’re also highly palatable and easy to overeat.

In recent years, researchers have linked higher intakes of UPFs to a host of chronic health conditions, including diabetes, cancer, and heart disease.

For instance, a recent study found that greater UPF intake was associated with type 2 diabetes. However, when the researchers broke down their analysis by food type, not all UPFs were as tightly linked to the condition. The closest ties were with sodas, savory snacks, animal-based products, and ready-to-eat dishes.

Additionally, there may be a link between highly processed foods and mental health conditions like depression.

Because of the growing evidence that UPFs are closely linked to worse health outcomes, many experts are calling for stricter regulations on these foods, like sugar taxes and warning labels on packages. However, it remains to be seen whether such restrictions in the ultra-processed food industry will take effect.

Federica Amati, PhD, MPH, a postdoctoral medical scientist and registered public health nutritionist with the Association for Nutrition (AfN), suggested making dietary changes slowly, particularly when it comes to reducing ultra-processed food intake.

“It’s clear that certain UPFs are worse for our health than others, so if you’re looking to cut down, start with the worst offender: soda. The evidence of links between high intakes of soda and poor health outcomes is now overwhelming. So, if you can cut it out of your diet, you’ll be doing your health a huge favor,” Amati told Healthline.

She recommended replacing soda with water with optional added fruit. “Or even better, switch to kombucha — a type of fermented tea, which contains live microbes. We know that fermented foods are likely to support your gut health and overall health,” she suggested.

“If you’re cutting back on your UPF intake,” Amati continued, “you don’t have to forgo all of your favorite foods — you can still enjoy chocolate, for instance.” She suggested looking for products that are at least 75% cocoa with as few ingredients on the label as possible.

“Dark chocolate,” she explained, “is rich in antioxidants and other beneficial plant compounds. So, if you choose the right kind, and eat it in moderation, it can actually benefit your health.”

“Finally, chips are high in salt and fat and contain no useful nutrients. I suggest swapping these for minimally processed popcorn. Because popcorn is made from whole grains, it contains nutrients, including fiber, which most of us don’t consume nearly enough of.”

“Just make sure you select a product that doesn’t contain a raft of additives, sugar, and salt,” she advised.

If you’re interested in learning more about the benefits of the Mediterranean diet or need additional guidance for reducing your intake of UPFs, talk with your doctor for further guidance.

A new study shows increased UPF intake is associated with higher BMI and greater overall adiposity.

Although the study is relatively small, it adds to the growing evidence that overall UPF intake — particularly soda intake — is linked to worse health outcomes.

“At the moment, most of us eat around 60% of our calories as UPFs,” Amati said. “Removing those products entirely would be nearly impossible, especially if we tried to do it all at once. Instead, make small sustainable changes, with the goal of reducing your total energy intake to around 20% from UPFs.”

“A good place to start is by replacing the UPFs that are highest in energy, like sodas and pastries,” Amati concluded.