Vitamin D — your skin converts sun into vitamin D, but a lot of people have this sun phobia.

维生素d—你的皮肤把日光转化成维生素d，但是很多人有太阳恐惧症。

youdao

They may start their lives vitamin D deficient, and then all they’re getting is vitamin D deficient breast milk.

他们生命一开始可能就是维生素D缺乏，接着他们食用的又全是维生素D缺乏的母乳。

youdao

People over age 50 need extra vitamin D because, for one thing, our skin becomes less able to make vitamin D as we age.

超过五十岁的人需要补充维他命D，因为，一方面，我们的皮肤随着年龄的增长，合成维他命D的能力也慢慢下降。

youdao

They play indoors. Everything's indoors. And so we're actually starting to see low levels of vitamin D in areas where the sun is plentiful."

VOA: special.2011.01.05

In some countries, milk producers add vitamin D to milk so children will get enough.

VOA: special.2009.04.21

Ultraviolet light from the sun changes a substance in the skin into vitamin D.

VOA: special.2009.04.21

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

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This is not adequate evidence to show that vitamin D deficiency causes diabetes nor that vitamin D supplementation is a legitimate treatment for diabetes.

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When people began relying heavily on a diet of bread at such a northern latitude, they probably became chronically deficient in vitamin D, for bread is generally low in vitamin D.

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