Vitamin supplements are good for us, but watch!

Supplement nutrients are safe even if we take it in a little more than the recommended daily allowance (RDA), according to Michael Castleman in Men's Fitness. But an overdose for some may pose serious problems.

Vitamin A: Intake of 25,000 IU to 50,000 IU may cause liver damage.
Vitamin B3: High doses cause "niacin flush," a feeling of heat, with reddening of skin, possibly itching. not harmful but annoying.
Vitamin B6: Doses greater than 2,000 mg a day may damage the nervous system.
Vitamin C: Too much has a laxative effect.
Vitamin D: Never take more than 1,000 IU a day. Overdose may be fatal.
Vitamin E: Doses greater than 1,200 IU a day may cause headache, nausea, diarrhea, fainting, and heart palpitations.
Vitamin K: High doses may destroy red blood cells and cause anemia.