How what you eat may affect mental health

More than 16 million U.S. adults report having a major episode of depression within the last year, according to figures from the National Institutes of Health.

While a number of factors are at play when considering who’s at risk, a new field of study called nutritional psychiatry looks at how diet can impact mental health.

“It’s the idea that maybe a psychiatrist should be asking you what was on your dinner plate last night,” CBS News medical contributor Dr. Tara Narula told “CBS This Morning” Tuesday. “What did you eat for lunch? The idea that food plays an essential role in our mental health in the same way that we think about it playing a role in cardiovascular disease, in our blood sugar management, in our gastrointestinal health.”

She notes that while the connection may not seem intuitive to many, research in the past few years has shown that a healthy diet is linked to a reduced risk of mental health conditions like depression and anxiety.

“The brain is a highly metabolic organ. It uses a lot of energy, a lot of nutrients. It’s always on and it depends on fuel, but not just any fuel. It’s like a car,” Narula said. “You want to give it expensive, high-quality fuel. That means foods that have the right nutrients, the right vitamins, and the right sources of protein because these form the building blocks for the neurotransmitters in the brain, for the cellular structures in the brain, and for the enzymes in the brain.”

Certain dietary patterns, including the Mediterranean diet — rich in fruits, vegetables, whole grains, nuts, seeds, and healthy fats — have been shown to reduce the risk of depression.

Specific nutrients and vitamins may help boost mood, too, including vitamins B & D, omega-3’s, iron, zinc, and magnesium.

“The idea is that when you eat these foods, essentially, many of them can become the basis for the brain chemicals the neurotransmitters,” Narula said.

Gut bacteria also plays a role in health, including mental health. Probiotics found in yogurt and fermented foods and prebiotics in leeks, asparagus, onions, and garlic can help boost your body’s own natural bacteria.

“The gut bacteria work as a defense layer preventing the flow of bad toxins across that layer that could potentially get into the blood and be pro-inflammatory,” Narula said. “They also work to help the communication in the neurons between the gut and the brain.”