Get some sun when you can. Not to excess, but a little sun is good for you. Your body USES it to make Vitamin d.

可能的话获得一些阳光。不要过量，一点点阳光对你有好处。你的身体靠用阳光制造出维生素d。

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Some vitamins, such as vitamin d, are not only essential in small doses, but also toxic in excess amounts. 14: minerals Twelve minerals in the table are known to be essential nutrients for dogs.

某些维他命，如小剂量的维生素d是需要的，可是过量会发生毒性。14：矿物已知对狗有效的矿物营养素有十二种。

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We do know that sun exposure will ensure an adequate level of vitamin D and because of a clever regulatory mechanism, will never result in excess vitamin D.

FORBES: Vitamin D: Still More Questions Than Answers

"I think the two biggest public health messages are to supplement calcium with diet and keep your weight down, " said Dr. Rosen, explaining that excess weight can drive down vitamin D levels.

WSJ: Vitamin D and Calcium Supplements May Not Stop Fractures