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 ...
Vitamin A: Why It's Important. Vitamin A is commonly known as the vitamin needed for good eyesight. Along with promoting vision, vitamin A is also vital for regulating genes, maintaining healthy skin, supporting the immune system and producing red blood cells.