Many dietary supplements have clean safety histories. For example, millions of Americans responsibly consume multi-vitamins and experience no ill effects.
Some dietary supplements have been shown to be beneficial for certain health conditions. For example, the use of folic acid supplements by women of childbearing age who may become pregnant reduces the risk of some birth defects.
Another example is the crystalline form of vitamin B12, which is beneficial in people over age 50 who often have a reduced ability to absorb naturally occurring vitamin B12. But further study is needed for some other dietary supplements.
Some supplements have had to be recalled because of proven or potential harmful effects. Reasons for these recalls include
- microbiological, pesticide, and heavy metal contamination
- absence of a dietary ingredient claimed to be in the product
- the presence of more or less than the amount of the dietary ingredient claimed on the label
In addition, unscrupulous manufacturers have tried to sell bogus products that should not be on the market at all.
Before taking a dietary supplement, make sure that the supplement is safe for you and appropriate for the intended purpose.