It may be more than coincidence that the decrease in the quality of Americans' diets has occurred simultaneously with increased reports of depression. While there are situations in which medication or psychotherapy are the only effective means to treat depression, studies show that dietary changes can sometimes be a mood booster.

Here are some ways to use food as a tool to fight depression:

Schedule an appointment with your physician to help ensure your symptoms are not signs of something bigger. Food allergies, thyroid abnormalities, nutrient deficiencies and other medical conditions all can cause depression.

Increase your intake of omega-3s. Research indicates that low levels of essential fatty acids can contribute to depression. Increasing intake of fish and flax or supplementing with their oils may improve your mood.

Pump up your diet. Food contains vitamins and minerals that are essential for making neurotransmitters that keep your mood in check. Aim for whole foods first rather than nutritional supplements or fortified foods. Whole foods contain many other compounds that help the vitamins and minerals work correctly. Focus on foods rich in B-vitamins and minerals, such as grains, nuts, lean meats, and fruits and vegetables.

Reduce or eliminate alcohol, caffeine, tobacco and food additives. Processed foods may contain food additives that can interfere with normal neurotransmitter functioning in some individuals.

Consult a physician before modifying your diet or health practices to treat depression. For additional information on nutrition and depression, visit the National Alliance on Mental Illness Web site: nami.org.

Laura Hunter, dietetic intern and Debra Boutin, MS, RD, dietetic internship director and associate professor at Bastyr University

Non-profit, accredited Bastyr University (bastyr.edu) offers multiple degrees in the natural health sciences, and clinical training at Bastyr Center for Natural Health (bastyrcenter.org), the region's largest natural medicine clinic.