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 ...
That is where eye vitamins come in. 1  Vitamin A: Vitamin A was the first vitamin thoroughly investigated for its health benefits, hence its name.  Vitamin B1: Also known as Thiamin, vitamin B1 acts as a coenzyme for certain chemical reactions in the body, assisting enzymes during those reactions.