Vitamins and minerals are measured in milligrams (mg), micrograms (mcg) and international units (IU).
Vitamins are placed in two categories, water-soluble and fat-soluble based on whether or not the vitamins can dissolve in water. Water-soluble vitamins include the B complex of vitamins and vitamin C. You don't store water-soluble vitamins in your body very well so they need to be replaced constantly through your diet.
Some vitamins and minerals need to be taken together for maximum effect.
Don't overdose: with few exceptions, like some vitamins from B complex, hypervitaminosis usually occurs more with fat-soluble vitamins, which are stored in the liver and fatty tissues of the body. These vitamins build up and remain for a longer time in the body than water soluble vitamins.
High doses of mineral supplements can also lead to side effects and toxicity. Mineral-supplement poisoning does occur occasionally, most often due to excessive intake of iron-containing supplements.
