If you’ve been turning to “comfort foods” to treat the blues, chances are you may be feeding a vicious cycle. New research links junk-food diets with vastly higher depression rates.

A recent British study analyzed the dietary intakes of 3,486 middle-aged Londoners, lumping them into one of two categories: the “processed food” group (heavy consumers of sweetened desserts, fried food, processed meat, refined grains and high-fat dairy) and the “whole food” group (favoring fruits and vegetables, fish, whole grains and legumes). Dietary habits were then measured against emotional status as monitored over five years. The result: Those who ate the healthiest whole-food diets had a 26% lower chance of being depressed, while those who ate the least healthy processed-food fare ran a 58% increased risk of depression! The linkage held true even when controlled for other factors ranging from activity levels to health status, including diabetes and heart disease.

Why might this be? One possibility is that nutritious whole foods such as fruit and vegetables help protect against the nutrient deficiencies that could endanger emotional equilibrium. For example, previous studies have linked low levels of folate, omega-3 fatty acids and vitamin D to depression. Other research suggests clinical depression actually dulls the sense of taste, possibly leading sufferers to favor processed foods with artificially enhanced sweetness, saltiness, etc. Regardless of what came first — the depression, or the poor diet — make a resolution to eschew junk food in favor of fruit, vegetables and other whole foods. By benefiting your body and losing excess weight, your mood is bound to lift.

Bonus: Try strength-training as well. 90% of formerly depressed seniors no longer met the clinical criteria for depression after a 12-week exercise regimen.

Published December 1, 2009