Vitamin D is made in the skin after sun exposure and can be taken in dietary supplements.

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For example, many drivers simply have scalded their fingertips on start buttons that have been baking in exposure to the sun.

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To encourage such developments the project's partners are trying to identify how the potency of herbs varies with exposure to the sun, the type of soil in which they are grown, and when and how they are harvested.

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But those of you lucky enough to enjoy a more southern exposure should spend 15 minutes in the sun every day without sunscreen.

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While it appears to darken in the sun like Transitions eyeglasses, the trigger is heat not UV exposure.

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Holick has a solution--limited direct exposure to the sun--that infuriates many dermatologists worried about the skin cancer risk. (A far better idea, they say: Take a supplement.) In 2004 he published his book The UV Advantage, touting the benefits of sun exposure, and was kicked out of the BU dermatology department, where he previously held a joint appointment.

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Exposure to the sun's rays normally generates Vitamin D in the skin, but applying sun block stops that process.

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Results of an animal study published by Ohio State University researcher Qinghua Sun in late 2010 revealed that early exposure to fine particulates led to the accumulation of abdominal fat and insulin resistance in mice even if they ate a normal diet.

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The university's Rowett Institute of Nutrition and Health suggested that promoting safe sun exposure and access to green areas during the summer months, including in the north of Scotland, would be a good strategy.

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