"If you're eating two energy bars a day, plus a protein shake that is vitamin fortified ... level is 1,000 milligrams (1,500 IU); the RDA is 30 IU. "There is no way to get an overdose from ...

Like most supplements, vitamin B complex can cause side effects, depending on the dose and type of vitamin B. Find a list of ...

A 4-ounce raw serving contains 67 micrograms (mcg) of B12, nearly 3,000% of the recommended dietary allowance (RDA) for adults. Beef liver is also an excellent source of vitamin A, other B ...