What Is the Best Diet for Mental Health?
Should you eat an apple—or a bag of Oreos? Go to McDonald’s—or the vegetarian restaurant on the corner?
When we make these everyday food choices, many of us think first of our physical health and appearance. But there’s another factor we may want to consider in picking foods: their impact on our mental health.
Whole-food diets heavy on the fruits, vegetables, and unprocessed protein can lift our moods and protect us from depression.
Who Benefits Most From a Healthy Diet?
First off, diet programs tended to work better for women. Why? Besides differences in hormones and metabolism, Firth conjectured, women seem to be in a better position to benefit. They’re more likely to be depressed, and, he says, they might have more discipline at following diets than men.
Also, the diet programs worked better if a dietary professional administered them—probably because the recommendations were sounder and the participants (believing in the dietitian’s authority) were more apt to follow them, Firth says. An earlier review of diet studies came to a similar conclusion.
One of the strongest studies in the collection suggested that diet could help people who were right in the midst of a major depressive episode. Researchers recruited 67 depressed people with poor diets, half of whom were instructed to follow a healthy, Mediterranean-style diet favoring whole grains, fruit and vegetables, legumes, low-fat dairy, nuts, fish, lean red meat, chicken, eggs, and olive oil while reducing sweets, refined grains, fried and fast food, processed meats, and sugary drinks. Across 12 weeks, they attended seven sessions with a dietitian who helped them set diet goals and stay motivated; they also received recipes, meal plans, and a hamper of food.
Can Your Diet Make You Happy?
It’s one thing to say that our diet might protect us from depression and other mental health issues. But could the foods we eat actually move the needle toward more positive emotions and happiness?
In a 2017 experiment published in PLoS ONE, researchers recruited 171 young adults with a diet low in fruits and vegetables, which meant three or fewer servings per day. These 18 to 25 year olds were split into groups: One got a basket of carrots, apples, and kiwi or oranges and was told to eat an extra serving of fruit and an extra serving of vegetables per day; another didn’t change what they ate.
Every day for two weeks, they answered questions about their feelings, mood, and happiness. At the beginning and the end of the experiment, they also filled out surveys about their anxiety and depression.
The diet group only managed to add one extra serving of fruit and vegetables to their daily diet. But that made a difference: Compared to everyone else, they had more energy, curiosity, creativity, and motivation; and they felt more engaged and purposeful in their lives overall—a greater sense of flourishing.
Surprisingly, though, the diet didn’t seem to change their mood or their feelings of depression and anxiety. That might be because the experiment was so short, the authors believe; while diet can give us a positive boost pretty quickly, it’s possible that mental health problems take longer to show up.
“The accumulation of factors such as low vitality, reduced motivation, and poorer socio-emotional flourishing may precipitate the development of psychological ill-being over time,” write researcher Tamlin S. Conner and her colleagues.
Eating for Well-Being
So, how should all this research inform our grocery list?
Most researchers are only willing to say that diet does seem to influence our mental health in some way, although they’re not sure exactly how. “There’s no real evidence to suggest that one diet works better than another,” says Firth.
However, the big picture is reasonably clear: Try to get enough fruits and vegetables—and avoid junk food.
Supporting that perspective, one paper reviewed the results of another 16 studies and found no differences between two relatively healthy diets. People who were eating a typical Western diet of fast food, salty snacks, desserts, and soft drinks became more depressed over time. But eating a classic healthy diet high in fruit and vegetables, seafood, and whole grains or a more Mediterranean diet—which includes lots of olive oil and more legumes, meat, dairy, and alcohol—both seemed to protect against depression.
In other words, at least as far as our mental health goes, we can stop obsessing about having a perfectly consistent diet—or whether we should go paleo or keto—and instead focus on cultivating healthy but sustainable eating habits. That’s the area where Firth wants to see more research, too, to figure out how to help people make lifestyle changes that last.
“It’s more important to actually stick to any healthy diet than it is to try and go for some aspirational perfect one that’s ultimately unfeasible or disgusting for you to stick to.
References:
https://www.mindful.org/what-is-the-best-diet-for-mental-health/