Should I have a blood test done periodically to insure proper vitamin and mineral levels?

It would be wise to first diagnose a vitamin or mineral deficiency before treating one. Unfortunately, there is no way to determine a deficiency beside having a blood test. If you are about to get your annual physical exam or you suspect a problem, ask your doctor to check for common deficiencies with these routine tests: CBC (to check blood cell count); SMAC (to check protein); lipid profile (to check cholesterol level); serum iron and serum ferritin (to check for iron deficiency or overload). Oftentimes, people who suffer from fatigue diagnose themselves as having anemia and self-prescribe iron supplements. However, iron overload (which affects 1 in 250 adult American males versus the 1 in 500 who are affected by deficiency) has the same symptoms. The consequences of taking unneeded iron can lead to liver disease, diabetes, hair loss, sterility, and heart disorders.