These supplements have greater risks associated with them than benefits so they are on this list. There is not enough information about long term effects of most of these. They might cause complications later in life that are not yet known. I also went on PubMed because a few supplements were actually put to the test and failed.

Most vitamins on the market at your local grocery store are really bad. Try to buy a vitamin that says "timed-release". It has different layers on the pill that break down at different times inside your body, giving your body a continuous stream of vitamins. After you take most generic vitamins, you pee it out within an hour, your body doesn't even use 5% of it. Plus there is a reason that early infant multivitamin supplementation is associated with increased risk for food allergy and asthma. Your body should get its vitamins from food, not pills made in factories. There have been people living past 100 years, and they sure as hell haven't been taking multivitamins.


Use a GOOD multivitamin if:
1. Poor diet
2. Very physically active and not getting enough vitamins from food.
3. You have a specific vitamin deficiency.

This is my favorite one, don't take supplements that claim that they raise your testosterone levels. Most of them are garbage. One of the most advertised ingredient in most of these is Tribulus Terrestis. It doesn't work, check on PubMed yourself, do your research. Your safer and better off taking pure testosterone pills rather than that crap. Although I don't recommend that either, because there could also be some serious side-effects associated with that if done incorrectly. And its very easy to do something wrong, especially if you don't know what your doing.

Most pre-workouts are filled with useless crap. All you need is Caffeine, that is the only ingredient in your preworkout that actually has value.  Energy drinks are also garbage, your body gets used to it, which leads to an addiction and reliance to this substance. No, you don't need it. It will only mess up your heart in the long run. There is still not enough studies done on energy drinks and their long term effects, but I am betting that the long term effects are nothing beneficial for you.

Increases vascularity...boosts blood flow...helps increase your hormone production while you sleep...there is nothing that proves these false advertisements.
This supplement has no real value to you if you are working out, the only value it would have is to diabetics:

"Arginine enhances wound healing and lymphocyte immune responses in humans."
"L-Arginine supplementation enhances diabetic wound healing: Involvement of the nitric oxide synthase and arginase pathways"
Metabolism Volume 51, Issue 10, October 2002, Pages 1269–1273

No this will not increase your growth hormone and make you super strong or better at your sport.

"Results indicate that 28 d of HMB supplementation (3 to 6 g × d-1) during resistance-training does not reduce catabolism or affect training-induced changes in body composition and strength in experienced resistance-trained males.
"Int J Sports Med 1999; 20(8): 503-509

Most nitric oxide boosting supplements use arginine as an active ingredient, so go read about arginine.