[Templar]

Unless your diet is near perfect, you're sure to be missing something that a vitamin or different supplement can handle. Multivitamins are usually not detrimental to your health, unless you have some sort of pre-existing condition. If you do have a very good diet, the worst thing you're getting is expensive urine because your body will excrete the excess.

But tell me, do you know if you're getting enough potassium every day? Do you know what the recommended dosage of it is? Maybe you do, but a lot of people don't, and that's the same with other vitamins and minerals that the body needs. The majority of people don't even know what the recommended levels are, let alone how much they consume each day in foods alone. If you do, then I'd say you're about 90% of the way there, and if you manage to eat the right foods to meet those dosages then don't bother with a multivitamin.

I know my diet is not perfect 100% of the time, so I take a multivitamin. It does not make me tired though... Getting up at 5:30 and running 5 miles or doing a P90X workout probably takes its toll later in the day though for me, but I doubt it has anything to do with my vitamins. I do notice that if I skip a couple of days of my vitamins, I feel worse.