Written by Corrie Pelc — Fact checked by Jill Seladi-Schulman, Ph.D.
The food we eat can play a much greater role in health and longevity than many people may realize. In fact, previous research suggests that 1 in 5 deaths around the world could be prevented by improving diet.
Now, two new studies recently published in the journal The BMJ examine the effects of ultra-processed foods on certain health conditions.
Another study from a research team at IRCCS Neuromed in Pozzilli, Italy says that adults with the lowest-quality diet and highest ultra-processed food consumption have an increased risk for heart disease and all-cause mortality.
What are ultra-processed foods?
Ultra-processed foods are a category of the NOVA food classification system designed by researchers from the Center for Epidemiological Studies in Health and Nutrition at the School of Public Health at the University of Sao Paulo, Brazil.
The NOVA system classifies foods into four different groups:
- Group 1: unprocessed or minimally processed foods
- Group 2: processed culinary ingredients (oils, fats, salt, and sugar)
- Group 3: processed foods
- Group 4: ultra-processed foods
Ultra-processed foods include products made in an industrial setting from ingredients that are mostly or entirely made in a laboratory or extracted from foods.
In general, ultra-processed foods can be identified in a product if at least one item on its list of ingredients is characteristic of the ultra-processed food group, which is defined by the following:
Examples of ultra-processed foods include:
- sodas and sweetened juices
- sports and energy drinks
- energy bars
- powdered and instant soups
- mass-produced and packaged bread and baked goods made with hydrogenated fats, sugar, and additives
- pre-prepared meals such as pizza, hot dogs, chicken nuggets, and fish sticks
- infant formulas
- meal replacement beverages
- mass-produced ice cream
- sweetened yogurt
Increased risk for colorectal cancer
Colorectal cancer — sometimes also called colon cancer or rectal cancer — is the third-leading cause of cancer death in both men and women in the United States, according to the American Cancer Society (ACS).
Dr. Fang Fang Zhang is an associate professor and chair of the Division of Nutrition Epidemiology and Data Science at the Gerald J. and Dorothy R. Friedman School of Nutrition Science and Policy at Tufts University, and corresponding author and co-senior author of the colorectal cancer study.
She told MNT that previous studies have linked ultra-processed foods to higher risks of obesity, high blood pressure, cholesterol, and some cancers, but few studies have assessed the association between ultra-processed food intake and colorectal cancer risk.
“The dietary risk factors for colorectal cancer include high consumption of red and processed meats and low consumption of dietary fiber and whole grains,” she explained.
“Ultra-processed foods include processed meats and are low in dietary fiber. Ultra-processed [foods] are also energy dense and contain a high level of added sugars, which contributes to obesity, a known risk factor for colorectal cancer. These motivated us to study the association between ultra-processed food consumption and colorectal cancer risk in the population of U.S. adults.” – Dr. Fang Fang Zhang, corresponding author and co-senior author of the colorectal cancer study
Upon analyzing data from over 3,200 colorectal cancer cases, Dr. Zhang and her team found men who ate the most ultra-processed foods had a 29% higher risk of developing colorectal cancer than those who ate the least ultra-processed foods.
However, researchers reported no correlation between overall ultra-processed food consumption and increased colorectal cancer risk in women.
Additionally, researchers found that certain types of ultra-processed foods placed both men and women at higher colorectal cancer risk.
For example, men who consumed more meat-, poultry-, or seafood-based ready-to-eat products and sugar-sweetened beverages had a higher risk, as did women who ate ready-to-eat and heat-mixed dishes.
Dr. Anton Bilchik, surgical oncologist and division chair of general surgery at Providence Saint John’s Health Center and chief of medicine at Saint John’s Cancer Institute in Santa Monica, CA, told MNT he found this study “fascinating.”
“We’ve certainly known about the higher risk of colorectal cancer with processed food, such as bacon and other processed products, which may be related to preservatives, nitrates, and a higher association with red meat,” he explained. “But this is really the first study describing ultra-processed food.”
Dr. Bilchik said he found it striking that the study showed an increase in colorectal cancer predominantly for men and it appears to be more associated with distal or left-sided colon cancers.
“What’s fascinating about what we’re learning, not only from this study but from other studies as well, is that the well-known risk factors such as obesity, diabetes, (and) smoking are not the only factors involved in an increased risk in colorectal cancer,” Dr. Bilchik said.
“Fresh food, what is commonly described as going into the supermarket and shopping from the outside in, plays an important role in being anti-inflammatory and in supporting the good bacteria and the good immune cells in fighting disease.” – Dr. Anton Bilchik, chief of medicine at Saint John’s Cancer Institute in Santa Monica
“Right now, we’re experiencing an epidemic of young patients being diagnosed with colon cancer under age 45,” Dr. Bilchik continued.
“Colon cancer is increasing among young people more so than any other cancer and every oncologist, both medical and surgical, is just totally perplexed by this enormous change. The only plausible explanation relates to what this paper is referring to, which is an increased use in processed food and the disruption of cells in our body and bacteria and immune cells that help fight cancer or reduce the chances of developing cancer.”
Increased heart disease and mortality risk
Researchers estimate cardiovascular disease is responsible for 32% of all deaths globally each year.
Clinicians have known for some time that nutrition plays an important role in preventing cardiovascular disease. And previous research links a diet high in ultra-processed foods to an increased risk for cardiovascular disease.
In this new study, lead author Dr. Marialaura Bonaccio, senior epidemiologist in the Department of Epidemiology and Prevention at IRCCS Neuromed in Pozzilli, Italy, and her team compared two different ways of looking at diet: the traditional way of rating food based on its nutritional content only, such as the Food Standards Agency Nutrient Profiling System (FSAm-NPS), and through the NOVA classification system.
“The aim was basically to see what type of perspective counts most in terms of defining the long-term risk of mortality of our participants,” Bonaccio explained.
The researchers found that people with the lowest quality diet based on the FSAm-NPS dietary index and the highest ultra-processed food intake based on the NOVA classification system were at the highest risk for both all-cause and cardiovascular death.
“However, when both these food dimensions were taken into account jointly, we found that a higher degree of food processing was more relevant for this increased risk than the poor nutritional quality of the diet,” Dr. Bonaccio added.
Dietary recommendations for disease prevention
Lauren Pelehach Sepe, a clinical nutritionist at the Kellman Wellness Center in New York, NY, said that a poor-quality diet, which leads to an imbalanced microbiome and inflammation, is a root cause of many chronic illnesses, including cardiovascular disease.
“Research has shown that inflammation is a key risk factor for cardiovascular disease,” Sepe told MNT.
“Although historically the focus of the treatment for cardiovascular disease was on lowering cholesterol, more and more we are seeing that even if you improve these blood markers, addressing overall inflammation is key to reversing and preventing cardiovascular disease.”
“We know that the standard Western diet, which includes many ultra-processed foods, is highly inflammatory, [which means] it also increases your risk of cardiovascular disease.” – Lauren Pelehach Sepe, clinical nutritionist at the Kellman Wellness Center
For people looking to improve their diet to help lower their risk of developing cardiovascular disease, colorectal cancer, and other health issues, Sepe suggests:
Add more healthy foods to your daily diet
Rather than focusing on what you cannot eat, Sepe said that “when people start making changes to the diet, they often feel like they have to make a major change overnight, which includes giving up all of their favorite foods.
“Start slow and add in some new foods each week,” she added. “Over time, the healthy foods will begin to ‘crowd out’ the old ones.”
Start cooking your own meals
“Most ready-to-heat foods are high in added sugars, salt, and additives, which are highly inflammatory,” Sepe said.
“Further, they are often contained in plastic containers, which particularly when heated, leach chemicals into the food you are eating. These are not only highly inflammatory, but they can also be carcinogenic.”
Take a good quality probiotic daily
Although diet is key to health, Sepe said that “adding in a daily probiotic will help to improve the balance of bacteria in the gut microbiome, which also helps to lower inflammation.”
This article originally appeared here and was republished with permission.