This week in nutrition news we are reminded that ultra-processed foods are bad for us. What does “ultra-processed” mean? Pretty much what you would think– “foods made using industrial methods and ingredients you wouldn’t typically find in grocery stores — like high-fructose corn syrup, hydrogenated oils and concentrated proteins like soy isolate”, according to this NYT article. Everything from sodas to flavored yogurts to boxed mac and cheese to breakfast cereals counts. To paraphrase one of food writer Michael Pollan’s Food Rules, “if it comes from a plant, eat it. If it was made in a plant, don’t.”
So far, so bad. At least we understand this. But wait a second: I just mentioned breakfast cereals in the same damning sentence as boxed mac and cheese. Surely these two foods are not equivalent in their so-called unhealthiness? Right. How processed a food is according to the Nova system some nutrition scientists developed is unrelated to its nutritional content. See below from the NYT:
The Nova system notably doesn’t classify foods based on nutrients like fat, fiber, vitamins or minerals. It’s “agnostic to nutrition,” said Maya Vadiveloo, an associate professor of nutrition at the University of Rhode Island.
That has led to debate among nutrition experts about whether it’s useful for describing the healthfulness of a food, partly since many UPFs[ultra-processed foods] — like whole grain breads, flavored yogurts and infant formulas — can provide valuable nutrients, Dr. Vadiveloo said.
Yeah. Maybe researchers should focus on the nutritional content of the food rather than the extent of its processing when deciding on nutritional recommendations. Just FYI, this isn’t my idea. Some other researchers developed a study to test this claim, which was published this week. Here’s what they found:
A new study demonstrates that eating primarily minimally processed foods, as they are defined by the NOVA classification system, does not automatically make for a healthy diet, suggesting that the types of foods we eat may matter more than the level of processing used to make them.
Comparing two menus reflecting a typical Western diet -; one emphasizing minimally processed foods and the other emphasizing ultra-processed foods, as categorized by the NOVA classification system -; the researchers found that the less processed menu was more than twice as expensive and reached its expiration date over three times faster without delivering any additional nutritional value.
“This study indicates that it is possible to eat a low-quality diet even when choosing mostly minimally processed foods,” said Julie Hess, PhD, a research nutritionist at the USDA-ARS Grand Forks Human Nutrition Research Center, who led the study. “It also shows that more-processed and less-processed diets can be equally nutritious (or non-nutritious), but the more-processed diet may have a longer shelf life and be less costly.”
Wow. If that’s true, then why are nutrition researchers telling us that ultra-processed foods are bad for us? I mean, if it’s possible to eat an equally nutritious diet that is a) cheaper; and b)lasts longer in the fridge or on the shelf, then what’s the problem?
There is research suggesting that eating ultra-processed foods may be linked to medical conditions like type 2 diabetes and heart disease. But this research is observational, so it’s hard to make strong conclusions. The NYT cites one small study of 20 adults who were given a diet of minimally processed food for two weeks and an ultra-processed menu for two weeks. On average, they gained weight on the ultra-processed menu and lost it on the minimally-processed menu, even though the menus were adjusted to be calorie-equivalent. In short, it looks like they ate more of the ultra-processed food.
Clearly, more studies are needed to try to sort this out. But what are we to do in the meantime? One expert in the NYT says this:
Cook at home as much as you can, using minimally processed foods, Dr. Davy said. “We can’t really say a whole lot beyond that at this point.”
Great. And I am aware that you, dear readers, are left not knowing more about nutrition than you did before you starting reading. But don’t worry, because I have some actual definitive nutrition news for you that’s not at all confusing. Here it is, again from the NYT:
Watermelon is really good for us. It’s hydrating, not very sugary (yes, this is true!), and it isn’t not heart-healthy (which is to say, they don’t know if it’s promotes cardiovascular health, but it doesn’t hurt).
Whew. That’s a relief. Now we can all proceed to enjoy lovely fresh summer watermelon with no hesitation. You’re welcome…
