Updated March 2022
Compared to children who ate few highly processed foods, children who ate lots of them showed more rapid increases in their weight and body mass index (BMI) measures, a recent British study has found. “These results echo lots of earlier studies that have also shown that diets high in ultra-processed foods tend to be associated with people being overweight or obese,” says Rajesh Kumar Garg, M.D., an endocrinologist and director of the Comprehensive Diabetes Center at the University of Miami Health System.
“Both kids and adults who eat lots of these industrially-designed foods have been observed to be at higher risk for diabetes, heart disease and a number of cancers.”
Examples of ultra-processed foods include frozen dinners, all-in-one lunchbox meals, sweetened drinks, packaged lunch meats, and hot dogs, packaged cakes, cookies, and pastries, and most salty snacks.
A large study, over a long timespan
Between 1998 and 2017, British researchers tracked the health of 9,025 children, half boys, half girls. At ages 7, 10, and 13, the families submitted 3-day food diaries that detailed what the children ate.
Once a year, when the children were between 7 and 24, the researchers gathered weight-related data on each child. Measurements included weight, BMI, waist size, and how much fat and lean tissue their body contained.
Intake of ultra-processed foods varied widely
“At the study’s outset, the research team divided the children into five groups, based on how much ultra-processed food they ate,” Dr. Garg said. The lightest consumers, in group 1, derived about 23% of their total daily calories from ultra-processed foods.
Group 2 children got about 35%; group 3, 43%; group 4, 53%. Youngsters in group 5 derived about 68% of their calories from ultra-processed foods, almost three times as many as the group 1 kids.
More industrial foods meant faster gains of weight and girth
The researchers compared the weight gained per year among children who ate the least ultra-processed foods with that gained among children who ate the most. The heavy consumers gained nearly half a pound more each year than the light consumers. “Overall, the years of childhood and adolescence, that much can add up to a lot of excess weight,” Dr. Garg says.
The waist sizes of heavy consumers grew by an additional three-quarters of an inch per year compared to the lightest consumers.
Possible pathways to overeating and other health problems
The exact reasons for the link between the high intake of ultra-processed foods and obesity are unclear. “Some evidence suggests that the hormones that control our metabolism are disturbed by certain chemicals in these foods,” Dr. Garg says, referring to insulin and glucagon. These two hormones work as a team to keep blood sugar levels in a healthy range and they both seem to be thrown off by certain food additives.
The nature of these unnatural foods
“Manufacturers want products to be tasty, cheap, and convenient, and to keep for a long time … also to look and taste appealing,” Dr. Garg says. To these ends, they add artificial colors, flavors, sweeteners, and thickeners as they engineer items many people buy.
“These items tend to be high in calories, sugar, salt, and fat, and low in terms of nutrition,” Dr. Garg says. They generally contain little or no fiber, vitamins and minerals, and other health-promoting substances such as antioxidants.
Ultra-processed foods are not designed for healthfulness
“Most food manufacturers don’t focus on how wholesome their products are,” Dr. Garg says. It is up to us, as consumers and as parents, to choose foods wisely.
We need to know the difference between healthy foods and those that lack real value and include artificial ingredients we should avoid. Most Americans need to do better because today, 58% of the calories eaten by people living in the U.S. are coming from ultra-processed foods.
Minimal processing? No problem
Some foods undergo no processing – fresh fruits and vegetables, fresh fish, meat, and poultry.
“The more fresh, simple foods you and your family eat, the better,” Dr. Garg says.
Many perfectly healthy foods are processed, but just a little, leaving their nutrients intact and with few, if any, added ingredients.
- Baby carrots
- Sliced mushrooms
- Cut-up broccoli flowerets
- Other ready-to-cook produce items
Many standard grocery items such as canned fish, beans and vegetables, and frozen produce have all been treated in ways that lock in nutrients and extend shelf life. Pastas and noodles are processed foods, but they contain only a few simple, natural ingredients and have been eaten by humans for thousands of years.
Fresh-baked bread falls into this middle range of more processed foods. Before plunking items into your grocery cart, ask yourself whether or not your great-grandmother would have eaten it, he says. If she would have, then it’s probably a reasonable choice.
If you can’t pronounce the ingredients, think twice.
Look at the ingredients listed for one major brand of beef bologna. The first two ingredients are beef and water. That’s fair enough, but then comes corn syrup, salt, potassium lactate, dextrose, sodium lactate, sodium phosphates, sodium diacetate, sodium ascorbate, and sodium nitrite. Do you want to put all of those chemicals in your child’s sandwich?
The five different kinds of sodium are all salts, and most Americans already eat way too much salt, which contributes to high blood pressure.
“Throughout human history, people have not been consuming these kinds of chemical additives, and we are all better off not eating them either, or at least eating as little of them as possible,” Dr. Garg says.
Overweight and obesity hits children of color extra hard
“US data shows that Hispanic and Latinx children in our country are nearly twice as likely to be obese as non-Hispanic white children,” Dr. Garg says. “It’s an issue with 10% of white children and nearly 20% of Hispanic kids.”
Overweight and obesity are also especially pressing problems for Black Americans, with much higher rates among Black children than their white peers. According to the U.S Office of Minority Health, non-Hispanic Black girls aged 6 to 11 are more than twice as likely as white girls their age to be overweight or obese. Black boys in those years are also at higher risk, although their risk is not as dramatically increased as it is for Black girls.
Ultra-processed foods and higher risks for serious illnesses
Children often maintain the eating patterns of their youth. Meanwhile, many links have emerged between increased risk of cardiovascular disease and death and high intake of ultra-processed foods. “Increased risk for several cancers has also been found in people who are heavy consumers of ultra-processed food,” Dr. Garg says.
Cancer risk rises for fans of ultra-processed foods. One study looked at the associations between intake of ultra-processed food and the cancer risks in about 105,000 adults. “These British researchers found that for every 10% increase in a person’s intake of ultra-processed foods, there was an increase of over 10% in their overall cancer risk and their breast cancer risk,” Dr. Garg says.
Italian researchers studied the association between diets high in ultra-processed foods and death due to any cause in a group of about 22,500 adults whom they followed for eight years. Adults who ate the most ultra-processed food had higher rates of death caused by heart disease and all other problems, as compared to the people who ate the least.
Drop these foods entirely
“There is no value to soda and to many foods sweetened with high fructose corn syrup,” Dr. Garg says. He suggests that you and your children drink water to quench thirst instead and choose fresh fruit for a sweet snack. “If you just don’t buy chips, candies, and cookies and don’t bring them home, avoiding them becomes so much easier,” he says.
Most supermarkets stock unprocessed foods such as produce, dairy, and meats, in the store’s outside aisles. Accordingly, many nutritionists advise people to do most of their shopping along those aisles.
Shopping and cooking tips
If you’re hooked on convenient ultra-processed foods that demand no work from you, you may have to adjust how you think about food and how you spend your time and money. Some fresh foods, such as berries and mushrooms, can be relatively costly, but not all healthy foods have high price tags.
Carrots and yams, collards, and cabbage are nutrient-packed and reasonably priced. These are just the kinds of brightly colored foods that nutritionists urge us to eat daily. Rice and beans, pasta with veggies in the sauce, and soups and stews that involve less expensive meat cuts can also be affordable.
“It does take more time and effort to make a healthy meal than to go to a fast-food drive-through,” Dr. Garg says. “But we’re talking about your family’s health for a lifetime. What better deserves time and attention?”
Be strategic when you cook at home — plan on having leftovers to cut down kitchen time. “A big pot of soup or a lasagna can last for days and improves over time,” Dr. Garg says. Many vegetables today come cut up and ready to roast or steam, with virtually no cutting or preparation needed.
“Don’t expect to revamp your family’s diet all at once,” Dr. Garg says.
“Changing habits takes commitment, time, and effort.” Perhaps you can limit fast food to one or two meals a week, at first, and then reduce even further.
If you do take yourself or your kids for a fast food meal, choose healthier options. “Steer clear of fried foods, like French fries and onion rings, and order small portions,” Dr. Garg says. “Do not buy sodas. Get skim or low-fat milk instead, or drink water.”
For your main dish, opt for a grilled chicken sandwich instead of a hamburger to reduce calories and fat.
Get the kids involved
“With proper supervision, kids can be a big help in the kitchen,” Dr. Garg says. “And cooking can be a time for them to practice reading and math skills.” They are likely to be highly interested in dishes they helped to prepare, even the healthiest ones, he adds.
Perhaps you have room for a garden that you and your child can nurture. Even a few pots on a sunny windowsill where your child tends some herb seedlings can be an exciting project for youngsters.
Take the long view
“It’s pretty well proven that obese children become obese adults,” Dr. Garg says. “They have higher levels of diabetes, heart disease, and certain cancers that are associated with obesity too.”
Most parents’ deepest desire is for their children to live long, good, healthy lives. While changing eating habits late in life has proven problematic for people in many studies, research also shows that childhood is the right time for establishing healthy eating patterns that promote lifelong mental and physical health.
Explore further, with help from the American Academy of Pediatrics.
Milly Dawson is a contributing writer for UMiami Health News.
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