Frustrated with the poor results she’d experienced from conventional depression therapies, she started looking at her health behaviors—especially her diet, which was a drab procession of colorless processed foods.
“I paid more attention to how I felt after eating rubbish food compared to eating balanced, nutritious meals,” she says. She also added exercise to her routine, and cut down on alcohol—which tended to depress her mood. “I just started being more aware of my own body,” she says.
While Jezeph noticed an improvement in her mood and energy levels, it took time for her to find the right combinations of foods to calm her gut issues, which included frequent bloating and gassiness.
“I tried so many different diets,” she says. After first focusing on low-cal, packaged “weight loss” meals—“I never looked at the ingredients”—she eventually found relief when she eliminated microwaveable meals and other packaged and processed foods. She read up on the latest diet and gut-health research, and swapped in whole foods known to combat gastrointestinal inflammation—stuff like beetroot, walnuts, ginger, and flaxseeds. The change was dramatic; her gut symptoms disappeared, and so did her depression.
“I believe from my own experiences that our gut health plays a huge part in our moods,” Jezeph says. She was so inspired by her own transformation that she decided to become a personal health and diet coach.
Do Experts Agree?
Not long ago, the idea that what you eat could affect your mental health would have sounded absurd to most experts. Not anymore.
“We know from several studies in mice and humans that there is an association between altered gut microbial composition and major depressive disorder,” says Emeran Mayer, MD, PhD, a professor of medicine, physiology, and digestive diseases at UCLA’s Geffen School of Medicine and author of The Mind-Gut Connection.
In a 2014 study in the Journal of Neuroscience, Dr. Mayer called the recent discoveries involving the human microbiome “explosive” in their mental health implications, and says they’ve initiated a “paradigm shift” in both medicine and brain science.
While many details have yet to be worked out, Dr. Mayer says low-grade inflammation caused by stress or a poor diet—or both—could contribute to unhealthy brain changes and disease. He mentions depression, but also anxiety and even autism spectrum disorder.
He’s careful to say that, based on the current evidence, most mental health disorders and diseases—including depression—probably spring from some “underlying vulnerability” in the brain, whether genetic or experiential.
“I think that for a majority of patients, depression starts in the brain,” he says.
That depression may then trigger an enhanced stress response—a rise in hormones like cortisol, which in turn produce inflammation—that affect the health of the gut’s microbes. Those microbes then produce “metabolites,” or byproducts of the gut’s metabolic processes, that return to the brain via the blood or nerves, and either reinforce or worsen the initial depression state. “It sets up a vicious cycle,” he says.
While he and other experts are still sorting out these cause-and-effect details, he says there’s already good evidence that changing your diet can improve your mental health.
What The Research Shows
A 2017 study in the journal BMC Medicine split 67 people with moderate to severe depression into two groups. One of the groups switched to an inflammation-fighting Mediterranean-style diet, while the other half continued to eat their normal diet.
After 12 weeks, 32% of the healthy eaters had experienced “remission” of their depression symptoms—compared to just 8% of the “control” group.
Dr. Mayer says some of the rodent research is even more compelling.
“In one experiment, they put mice on a chronic stress paradigm, and the mice developed depression,” he says. “They found these depressed mice had altered microbial composition, whereas before their [gut] microbes were normal.” The researchers then “transplanted” the altered microbes into healthy, depression-free mice. “Those mice then started showing depression symptoms,” Dr. Mayer says.
All this research is “just scratching the surface,” he says, and what we know today is dwarfed by what we don’t know. But it’s clear that the health of your gut plays a role in the health of your mind.
So What Should You Eat?
Skip the probiotic potions—at least for now, Dr. Mayer says.
While some naturally probiotic foods—sauerkraut, say, or kombucha—may do your gut some good, there’s not enough evidence backing probiotic-infused smoothies or supplements, he says.
Instead, the current evidence supports a whole-foods diet heavy on all colors of vegetables and low in sugar and animal fat, he says. “The Mediterranean diet has many components, like olive oil and nuts, that exert an anti-inflammatory effect—and so may reduce immune reactions,” he explains.
Also, healthy gut microbes thrive on the kinds of “indigestible fibers” found in plants—so you want plenty of those in your diet, he adds.
Jezeph agrees, and advocates an “eat the rainbow” approach to healthy foods.
Different colored fruits and vegetables—orange carrots, purple potatoes, red berries—contain different healthy bacteria and inflammation-fighting antioxidants, she says.
By eating the rainbow, “you improve the variety of bacteria in your GI tract,” she says.
For many suffering from depression, that may be enough to lift the clouds.