LIKE BEARS fattening up before hibernating, many people experience food cravings and fatigue as winter approaches. Some people also report feeling unusually blue when the temperature drops and nighttime comes earlier. Interestingly, certain nutrients may help ward off the winter blues.

Doctors still have the best treatments for seasonal depression, which keeps a person feeling down not just for a day or two, but for days on end. The treatments include medicine, counseling and therapy with special lights.

Along with that, outdoor walks and getting enough vitamin D and certain fish may help people to pull through the dark winter, whether their seasonal mood shift becomes a severe case of depression or not.

Feeling SAD

Seasonal Affective Disorder, SAD for short, generally makes people feel down or lethargic in fall and winter, and better during spring and summer (though some people do have the opposite pattern).

Scientists aren't sure exactly what causes SAD, but research shows that shorter days and less sunshine do affect brain chemicals.

A Swiss study of people with seasonal depression confirmed that these people crave carbohydrate-rich foods during fall and winter, and their blood sugar rises faster then, too.

We know that eating carbohydrates can raise levels of serotonin, a natural mood-booster. So people may be self-medicating their sad feelings with cookies and other sweets.

Instead of cookies, studies show that mild exercise, sunshine, vitamin D and fatty fish may help people with SAD.

Russian scientists found that treatment with special lights or stationary bicycling an hour daily improved moods and helped people lose weight gained due to seasonal depression.

The Levity (Light, Exercise and Vitamin Intervention Therapy) trial in Seattle suggested that brisk walks and vitamins can ease mild to moderate depression. Specifically, participants walked outdoors in the sunshine for 20 minutes five days a week. They also took a vitamin supplement equivalent to a vitamin B complex plus 200 micrograms of selenium and 400 units of vitamin D.

The happy vitamin

Vitamin D is being studied all by itself as a treatment for SAD. We know people's vitamin D levels fall in autumn and winter. That's because we get most vitamin D from sunshine--UV light hits the skin and triggers a series of chemical reactions to create vitamin D.