Vitamins are chemicals present in nature that our bodies require to prevent certain nutritional deficiency diseases. Think scurvy (from inadequate Vitamin C) that was prevented by citrus fruits, hence the origin of Limey for a British sailor. Or pernicious anemia (meaning deadly anemia), prevented by Vitamin B12, originally found in liver extracts (where it is concentrated), hence your grandmother’s cod liver oil.
US Preventive Services Task Force Report
Last month the USPS Task Force released a comprehensive analysis of studies that looked at possible benefits of vitamins and vitamin/mineral combinations in reducing cancer and preventing heart disease. The report reiterated that they found no evidence that vitamins helped either class of disease, and several specific examples (as with beta carotene) where vitamin supplements were harmful.
Their clear recommendation, which I support, is not to take vitamin or mineral supplements in hopes of prevention of cancers or heart disease. They don’t work. Vitamin supplements are only useful for specific, defined nutritional deficiencies.
Supplemental vitamins are not needed by the vast majority of people who eat a reasonably varied diet that includes meaningful amounts of plant material. The very large vitamin pills are also packed with various minerals, from calcium to selenium to potassium, again none of which supplements are required by most.
Limited Vitamin Supplement Indications
Probably the only vitamin that some of you may need for general purposes is Vitamin D, which is made by our skin in response to sunlight and which, in northern climates such as ours, may be significantly low. We test for that and recommend supplementation where indicated. Other limited exceptions include women who are pregnant or who might become pregnant, when vitamins are recommended primarily to prevent folic acid deficiency (which can harm the fetus), and a specific multivitamin combination in the treatment of macular degeneration of the eye.
In general, save your money. If any generally useful vitamin indication is documented, we will all hear about it promptly and I will be happy to comment in detail.