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 ...
Vision. A deficiency in vitamin A can cause your eye's photoreceptors to deteriorate, which leads to vision problems. Eating foods rich in beta-carotene may restore vision, lending truth to the old adage that carrots are good for your eyes. Brain Health.