Metric system. Metric system, international decimal system of weights and measures, based on the metre for length and the kilogram for mass, that was adopted in France in 1795 and is now used officially in almost all countries.
However, if taken in large doses, vitamin D side effects may include: Thirst; Metallic taste in the mouth; Increased urination; Decreased appetite; Weight loss; Constipation; Vomiting; Diarrhea; Itchy skin; Loss of muscle tone; Irritability; Tiredness; Sore eyes; Pain in the bones and joints ...
These health related issues include problems in the eyes. By taking the recommended dietary intake of important vitamins, not only will you be reducing the risk of eye problems, you will also be improving your eyesight as well. Here is a list of essential vitamins to help improve eyesight: