Sunlight provides your body with much needed vitamin d, and stimulates production of endorphins and other brain chemicals that relieve depression and improve moods.

阳光为你的身体提供所需的维他命d，而且刺激安多芬以及其他一些大脑化学物质的产生，从而能够舒缓压力和改善心情。

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A lack of sunlight, however, can sometimes lead to a condition known as seasonal affective disorder (SAD), a mood illness which can lead to depression.

人体缺少阳光可能会引起一种被称为“季节性情障碍症(SAD)”的情绪疾病。这个疾病有可能导致抑郁症。

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Winter depression more closely related with less sunlight.

冬季抑郁症多与阳光照射少密切相关。

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Light is used to treat medical conditions including seasonal affective disorder a cyclical depression often tied to low sunlight as well as skin, eye and gastrointestinal conditions.

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