A decade ago, most people had never heard of ultra-processed foods.
But that changed in 2019, when Kevin Hall, then a scientist at the National Institutes of Health, published a study that shocked the nutrition world.
Hall recruited a group of healthy adults and put them on two different diets. One diet consisted of mostly homemade, unprocessed foods like fresh fruits and vegetables, nuts, whole grains, Greek yogurt and salads with grilled chicken. The other contained an assortment of packaged foods: sugary breakfast cereals, blueberry muffins, canned ravioli, chocolate milk, goldfish crackers, potato chips and other staples of an ultra-processed diet.
Hall found that the participants consumed an extra 500 calories a day on the ultra-processed diet and quickly gained weight — even though both diets were matched for nutrients such as salt, sugar, fat and fiber.
The study created a paradigm shift in how we think about nutrition, prompting public health experts to realize that it’s not just the amount of salt, sugar, fat and calories in our food that matters for our health, but also the extent to which our food undergoes industrial processing.
Do you think that the major driver of obesity and diabetes is what we’re eating?
Not just our food but the overall food environment. That’s one thing we have to be careful about. Our food environment is not just about our food — it’s the marketing of food, it’s how convenient and cheap and tasty it is. I think that’s a natural progression of this desire we’ve had to adequately feed the growing population. Decades ago, we were worried about mass starvation, so we put in place policies and incentives to mass produce protein and calories at an industrial scale, and that’s created a calorie glut.
In the book, we calculated how many calories per person per day are grown in the major food commodity crops in the United States — that’s wheat, soy, corn and rice. Just in the U.S., we grow 15,000 calories per person per day. And the food system is designed to get rid of those calories. We feed a huge chunk of them to animals primarily for factory farming. We find ways to create biofuels out of corn and soy. And then we’ve come up with really ingenious ways in food technology and food science to create cheap inputs for ultra-processed foods.
One of the much-talked about inputs these days is high-fructose corn syrup. We use corn to create a sweetener that didn’t exist before the middle of the 20th century, and it’s now become the major calorie-container sweetener in ultra-processed foods.
I have to ask: Do you eat ultra-processed foods?
I do. I eat some of the bad ones — the tasty treats — but I treat them as recreational substances. I also eat ultra-processed foods that from a nutritional perspective are pretty good even though they contain certain additives. I use, for example, a marinara sauce that’s low in sugar and sodium, but when I’m making a nice pasta dish it cuts down the preparation time. I’m not going to make a marinara sauce from scratch. Just because something is ultra-processed doesn’t necessarily mean it’s bad for you.
Read the full story: This scientist studies ultra-processed foods. Here’s what he eats in a day. (WaPo)
Hall has written a new book, “Food Intelligence: The Science of How Food Both Nourishes and Harms Us.”
