Back in the late 1970s, when Louise and I were running a residential treatment program and school for abused and emotionally disturbed kids, we took the children off the standard institutional diet. Out went the dyes, the artificial flavors, the sugary cereals and the boxed dinners, and in came real (vegetarian) food cooked fresh every day from scratch.
While it’s impossible to know how big a factor that was (we were also on a remote forest-covered lake and had some great therapists), kids who were given up on as being incorrigible or uneducatable were soon ready for reintegration into the normal school system and a foster home.
While Ben Feingold told me diet was a huge factor in kids’ behavior, and we did a small study on salicylates in their diet that I published in 1980 in the Journal of Orthomolecular Psychiatry, I was always skeptical. Until now.
Last week, researchers at UC San Francisco published a small trial in JAMA Psychiatry that looked at what happened to people clinically diagnosed with depression stopped eating ultra-processed food (UPF). For four weeks they ate a diet that cut their UPF consumption by more than 85 percent.
And, sure enough, their depression eased with their depression eased, with moderate to large improvements showing up on three separate measures. Their anxiety scores got a little better, as well.
Similarly, in 2017 an Australian team led by Felice Jacka ran the SMILES trial, taking 67 people with moderate to severe depression and giving half of them coaching toward a Mediterranean-style diet (fresh foods, mostly vegetarian/pescatarian) while the other half got supportive counseling from trained professionals. After twelve weeks, 32 percent of the food group were in full remission from their depression, compared with of the the people who just got counseling.
Two years later, researchers at Macquarie University tried a three-week version of the same study with depressed university students. The students who cut back on processed food and ate more vegetables, fish and olive oil reported significantly less depression, and the improvement was still clinically evident a full three months later.
Then came the really big large-population studies, a gold standard in health science.
Harvard researchers followed almost 32,000 nurses for decades and found that the women eating the most ultra-processed foods had about a 50 percent higher risk of developing depression than those eating the least. (Of particular interest: artificial sweeteners stood out as the worst offenders.)
A massive review in The BMJ pulled together 45 separate analyses and tied these UPF foods to 32 different kinds of harm, with anxiety and other common mental disorders at the top of the list.
And just this week another British study looked at more than 46,000 people born around the end of postwar sugar rationing. Those who spent their first thousand days of life — from the womb to their second birthday — under sugar and meat rationing were less likely to be diagnosed with depression or anxiety as adults.
Why would a bag of potato chips or too many sodas slam into your mood with such impact? The UCSF team suspects the gut-brain connection.
Their idea is that the emulsifiers, preservatives and other industrial additives in these products wear down the gut’s protective lining, which sets off low-grade inflammation that travels through the whole body and triggers a freak-out (my term, not theirs) in the brain. Dr. Nyasha Chagwedera, who led the study, put it this way.
“Junky processing may harm your gut in ways that ripple up to your brain.”
Older cultures wouldn’t find any of this surprising. They were not just careful about what they ate, but had a story about every edible plant or animal in their world; it’s how both cultural and “safe-to-eat” information was transmitted from generation to generation. And it worked until we turned our food system over to the giant corporations and their “food scientists” to figure out how to make things more profitably.
As a result, today the CDC says fully 55 percent of the calories Americans eat now come from ultra-processed products, and for our kids it’s closer to a shocking 62 percent. We — and our kids — are up against some of the most well-paid scientists and greedy capitalists on the planet.
So try this: give yourself four weeks, the same stretch the UCSF volunteers got. Read the ingredient list on everything you buy, and if it’s got anything on the list that you wouldn’t find in your own kitchen, put it back. Cook simply, and notice how you feel in week one and again in week four. And if someone you love is struggling with depression or anxiety, pass this along and offer to do it with them.
No country should have to accept a food supply that makes its people sick and sad because that’s what’s most profitable, and the science is now on our side when we say so out loud.
Thank you Thom. This makes complete sense to me. I eat this way as much as I possibly can. I do read the ingredients on labels on everything I buy.
Hmm. While this information didn't surprise me, I now find myself if another manifestation of the effects of processed foods might not be SAD, or the Seasonal Affective Disorder version of depression that sets in in winter and stops in late spring might not be, at least in part, made worse by the fact that we generally eat fewer salads, fruits and cooked vegetables in the winter, and begin eating more sugary treats, from October through Easter. I know light plays a part, as does spending less time outdoors, but I think this is worth experimenting with. Nutrient-dense, chemically unaltered dried, canned or frozen fruits and vegetables should probably take up a higher number of our winter calories than they do. Tip of the iceberg, maybe.