DAVID SIMON MD: According to the 5,000-year old system of natural healing known as ayurveda, everything in the biological world moves in seasons, cycles, and rhythms of expansion and contraction. Fall and winter are seasons of contraction, and many people notice subtle and not-so-subtle changes in their mood and physiology as the days grow shorter.

Those with an underlying vulnerability may experience depression in the period between the autumn equinox and the winter solstice. Seasonal Affective Disorder is the formal name for the depression linked to decreased hours of sunlight. Other symptoms include fatigue, weight gain, irritability, and withdrawing from social activities.

At some level, I suspect that these symptoms are nature's encouragement for us to hibernate, slow down our metabolic activity, and go into a more internal state of processing in preparation for spring, which is a time of expansion and rejuvenation. While ayurveda and other traditional healing arts recognize that our bodies change and have different needs during the colder months, our society expects us to maintain our usual fast pace and work the same number of hours during winter, making no allowances just because the nights are longer than the days. As a result, a dysrhythmia develops between our biological rhythms and the rhythms of nature.

To offset this disruption, the following ayurvedic practices are helpful:

~ Develop a regular meditation practice throughout the year and spend extra time meditating during winter. During meditation, your breathing slows, blood pressure decreases, and stress hormone levels fall. You go beyond the mind's mental agitation into an oasis of inner silence and stillness.

~ Follow nature's rhythms: Rise with the dawn and get to bed earlier.

~ Eat warm, heavier foods such as soups, cooked whole grains, and nourishing stews. Limit your consumption of dry or raw foods such as nuts, chips, and uncooked vegetables as these tend to aggravate the body's nervous system and digestion.

~ Use calming, grounding aromas in your home and workplace. Scents including orange, lavender, neroli, sandalwood, vanilla, orange, basil, and clove can calm your mind and increase the mood-enhancing neurochemicals in your mind and body.

~ Perform a daily oil self-massage. (Find complete massage instructions at the Chopra Center's on-line library ).

~ Cold or windy weather can cause imbalances in the body's natural equilibrium, so keep your body warm and your head covered.

Scientific studies suggest that exposure to artificial light may affect some of the neurochemicals changes of SAD. In addition, a powerful way for people - especially those who live north of the 33 ° parallel - to experience natural light and emotional healing is to spend a week or two at the Chopra Center in Southern California, which enjoys abundant sunshine throughout the year. We offer a variety of programs and treatments that provide many profound healing benefits for those coping with SAD, emotional turbulence, and other health challenges.