"If you start using face oils and heavier creams now, you might avoid the dry-skin trap of winter, " said Dr. Colbert.

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Winter, city life (with the concomitant shadows cast by tall buildings) and dark skin in dark climates all reduce this action.

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Vitamin D is incorporated in the body when skin is exposed to sunlight of a certain wavelength but in the UK, during winter months, UV-B radiation can be insufficient to properly support vitamin D synthesis in the body.

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Skin exposed to sunlight produces vitamin D, and many North Americans are vitamin D deficient in the winter.

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