When Dr. Michael Hurd counsels patients with anxiety or depression, he often asks what they’re eating. “If it’s not a balanced diet then that’s something to address right there,” says Hurd, a psychotherapist in Bethany Beach. “I would not suggest looking only at diet as playing a role in anxiety or depression, but it’s often part of the mix.”

He’s not the only one to spot a link. Studies suggest that food can influence brain neurotransmitter systems that affect mood—at least temporarily, according to an article in the Dartmouth Undergraduate Journal of Science. The relationship, however, is complex and depends on the time of day, the food’s composition, the amount and the subject’s overall health and dietary history. Nevertheless, many choices that might improve your mood are good for you in other ways.

An ancient approach for modern studies

Hippocrates once said, “Let food be your medicine, and your medicine be your food.” If that’s the case, then you want the best medicine you can find. According to Dr. Eva Selhub, a contributing editor to a Harvard Medical School health blog, the brain is much like a luxury car: it functions best when it gets premium fuel.

Mary Williams, a registered dietitian with Christiana Care Health System, agrees. “There is definitively some link between food quality and mood,” she says.

Bryan Drain began researching how food could influence his mood when he was diagnosed with depression. He became so interested in the subject that he wound up becoming a dietitian. Today he’s a medical nutrition therapist at Beebe Healthcare.

Drain found a correlation between the freshness of his food and his mental outlook. Fruits, vegetables and meats are more nutrient-dense when they’re locally sourced, he says. “They’re not sitting on a truck, or in a freezer or on a shelf for a long period of time.”

Studies of traditional diets in the Mediterranean and Japan—which are high in vegetables, fruits, unprocessed grains and seafood—have shown that the risk of depression is 25- to-35-percent lower than the traditional Western diet.

Roller-coaster rides

“Low-premium fuel” includes diets high in processed or refined products. Sugar is a known pick-me-up. But proceed with caution. Even whole wheat toast with organic jam has its drawbacks.

“It’s great for when you need serious fuel—perhaps before working out,” says Liz Abel, a licensed clinical nutritionist and the owner of Wilmington-based Free + Abel. “For others, these food examples are likely to spike blood sugar levels.” A crash usually follows the lift.

Drain, who works with diabetics, is not a fan of pairing carbs with carbs because it’s too easy to overdose on them. A high-carbohydrate item such as a whole English muffin is really two servings and more than a teaspoon of jam is too much.

Abel recommends an afternoon snack of an organic apple and natural nut butter without added sugar or hydrogenated oil. “Use snack time to increase your veggie intake, which we are all low on,” she says.

Coffee is another quick fix that can change your mood—for better or worse. Caffeine interacts with adenosine receptors in the brain—with regulated sleeping and waking cycles—to induce feelings of alertness and energy. Some people, however, get anxious or irritable with even one cup. Even those who tolerate caffeine can get a coffee buzz if they drink one too many. Instead of feeling more alert, they’ll develop brain fog. Once the caffeine is out of your system, you’ll feel fatigue that may prompt you to order another latte—and another.

The ingredients that you add to coffee can also play a part. “I make sure my clients are not addicted to coffee—or the sugar, sweetener, cream or whatever else they are adding to it—then have them use it as needed rather than as a crutch,” Abel says.

Feel-good foods

Like adenosine receptors, serotonin regulates sleep. It also controls appetite and impulse control, and increased serotonin levels are linked to elevated moods.

To make serotonin, the body needs tryptophan, which is found in all nuts and seeds, both of which are also good sources of fiber, vitamins and antioxidants. Other foods with tryptophan include oysters, clams, pineapple, plums and eggs. The most celebrated source is turkey. You’ve no doubt read seasonal articles that link the Thanksgiving turkey to drowsiness.

Tryptophan, however, must work with other amino acids to create serotonin, and like a recipe, these “ingredients” must come together in a specific order within a certain time period. “Tryptophan, found in food, is one of the amino acids that has to wait,” Abel says. “Researchers are exploring the combination of all amino acids—when eaten together.”

Since more than 90 percent of serotonin levels are found in the gastrointestinal tract, good gut health is a plus, Williams says. “We see a lot of GI doctors ordering probiotics; I think we will see more of that.” Good gut health also means avoiding sugar and processed foods.

Reducing inflammation for mental health

When it comes to treating your mind and body, you can’t go wrong with salmon, which is rich with tryptophan. (For an extra potential boost, pair it with eggs—either for breakfast or in a salad.) Salmon’s nutritional benefits also help balance cholesterol and lower blood pressure, and it’s a source of omega-3 fatty acids, which have anti-inflammatory properties.

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Many think of sore muscles or a bruise when we hear the word inflammation. But when inflammation occurs inside the body, you may feel tired and achy.

A Danish study, published in AMA Psychiatry, found that depression and other mood disorders might be the brain’s response to inflammation. According to the study, patients with an autoimmune disease were 45 percent more likely to have a mood disorder, while any history of infection increased the risk of a mood disorder by 62 percent.

In a Norwegian study of 22,000 people published in the American Journal of Clinical Nutrition, participants who took cod liver oil were 30 percent less likely to have symptoms of depression than the participants who did not take omega-3 fatty acids. (Walnuts and green leafy vegetables are other sources.)

The benefits of fish might explain why so many people in an informal Facebook poll said sushi was their mood elevator. Rolls often include salmon and come with ginger, which has anti-inflammatory and antioxidant properties. Ginger is closely related to turmeric, which is being heralded as a wonder spice, although studies have been inconclusive, notes Williams.

A TEAM APPROACH

To see if food can improve your mood, incorporate more:

• Omega-3 fatty acids (certain types of fish, flaxseeds, nuts, leafy vegetables)
• Tryptophan (bananas, oats, soy, nuts, peanut butter, sesame seeds and lean poultry)
• Vitamin B (beans, legumes and whole grains)
• Vitamin D (orange juice and mushrooms)
• Plant-based foods that are fresh and preferably locally grown

Avoid:

• Sugar
• Processed foods (comes already made in a packet, can or carton)
• Fatty meat and dairy products
• Refined carbohydrates (white bread)

Keep track of what you eat and how you feel. “Mindfulness is the big theme in psychology and therapy these days,” says Hurd. “It boils down to self-awareness combined with self-respect in how you live your life in the here and now.”

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