I take b - complex vitamin with my daily men's vitamin. i take it to boost my energy. can to much b, hurt?

Yes.: Even though B vitamins are water soluble and not stored in our fat like the fat soluble vitamins (A, D, E, K), too much of certain Bs, like B6 and B3 (niacin,) can get you in trouble. Going above 200 mg a day of B6 has the potential to cause numbness and other nerve problems. High doses of Niacin (2000 mg a day) can lead to elevated liver enzymes, jaundice and nausea.