Vitamin D Exclusively breastfed healthy, full-term infants from birth to six months who have adequate exposure to sunlight are not at risk for developing vitamin D deficiency or rickets.

维生素D 纯母乳喂养的，健康足月宝宝从出生到六个月如晒太阳时间足够，就不会有维生素D缺乏症或佝偻病风险。

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Rickets occurs because of a deficiency in sunlight exposure, not because of a deficiency in human milk.

佝偻病的发生原因是缺少日照，而不是因为母乳营养物质的缺失。

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Signs of deficiency would be rickets (in children), joint pain, bone deformities, poor growth.

不足的迹象，将佝偻病(在儿童)，关节疼痛，骨畸形，穷人的增长。

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But is the prevention of severe vitamin D deficiency such as rickets all we need to know?

FORBES: Vitamin D: Still More Questions Than Answers

But in northern Europe, diseases related to vitamin D deficiency, such as rickets, would have become common.

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Still, we can try to correlate vitamin D levels with obvious deficiency diseases such as rickets, but the environmental studies that look at other possible effects are problematic.

FORBES: Vitamin D: Still More Questions Than Answers