A multivitamin is a dietary supplement that typically combines vitamins, minerals and sometimes other nutrients that your body needs to function normally. Multivitamins can come in the form of tablets, capsules, powders or liquids. The purpose of a multivitamin is to provide the recommended daily allowance of all of the necessary nutrients for humans in a single supplement. Multivitamins are meant only to supplement a normal diet and should not be used to replace food.
Adult men and women have many of the same nutritional requirements with a few exceptions. The most notable difference is the amount of iron that men and women need. According to the National Institutes of Health, women between the ages of 19 and 50 need 18 milligrams per day, whereas men in the same age range need only 8. Men are much more likely to overdose on iron. The other difference typically involves what are known as gender-specific blends that are advertised to promote vitality in men and women. These blends are typically made up of a combination of herbs and other extracted nutrients and are present only in very small quantities in multivitamins. Some herbs in male multivitamins include saw palmetto and lycopene. Female-specific blends often contain dong quai and cinnamon bark.
Three key differences exist between adult and children's multivitamins. The first involves the amount of iron they contain. While most adult multivitamins contain some iron, many children multivitamins do not. This is because it is very easy for children to overdose on iron, which can be fatal. According to the "Canadian Medical Association Journal," iron is a leading cause of death due to poisoning in young children. The second difference involves the dosage of each multivitamin. Children only require a portion of the vitamins and minerals that adults need. For example, children require only 110 milligrams of magnesium per day, whereas adults need 350. The third difference involves the form of the multivitamins. Children's multivitamins typically come in chewable form and are flavored.
Multivitamins for seniors are generally very similar to adult multivitamins. They do include elevated levels of certain nutrients that are especially important for seniors. These commonly include calcium, magnesium and vitamin D, which aid in preserving done density and staving off osteoporosis. Dr. John Cannell of the Vitamin D Counsel recommends 4,000 international units of vitamin D per day for seniors. This is 10 times the RDA of 400 international units. Various B vitamins and other nutrients may also be elevated depending on the manufacturer.
High-potency multivitamins include elevated levels of certain vitamins and minerals. Typically, B vitamins are included in high amounts. The RDAs of vitamins B-6, B-12 and niacin are 2 milligrams, 3 micrograms and 20 milligrams respectively. Doses of these vitamins in a high-potency multivitamin may be in the neighborhood of 10 milligrams, 25 micrograms and 50 milligrams respectively. The B vitamins aid in energy metabolism, which makes them desirable. The body can safely excrete excess B vitamins because they are water soluble. High-potency multivitamins promise increased energy, better health and overall performance. Many also include added antioxidants as well as fruit and vegetables blends. They typically cost more than normal multivitamins.