Despite the impressive marketing claims by sports supplement vendors and pro bodybuilders who are sponsored by them, most sports supplements sold to bodybuilders simply do not work. The only effects they have on you are the placebo effect (a positive effect based solely on the power of suggestion) and the financial effect (you are basically sponsoring the sport when you buy supplements, which is of course a good thing). The only sports supplements of which I believe that they may have real beneficial effects for bodybuilders are those discussed below.

The only sport supplement that I believe is really beneficial to all bodybuilders is protein powder, because protein is really an essential nutrient for muscle growth. I consider protein powder as a food product rather than a supplement, because it is isolated from natural food products such as milk and eggs.

The only other sport supplement that true natural bodybuilders could benefit from is creatine monohydrate. However, I do not think that creatine supplementation has any long term beneficial effects.

I believe that all other sports supplements currently on the market have no significant benefit for bodybuilders, do not work at all, or should not be part of true natural bodybuilding.

Note that it is well possible to eliminate the need for sports supplements completely, simply by eating large enough quantities of meat and/or fish. By eating about 1 lb of meat and/or fish per day you fully cover your daily needs of quality protein and creatine, eliminating the need for any supplementation. Eating such high amounts of meat or fish can, however, have a few disadvantages: meat and fish can contain lots of saturated fats and cholesterol, they can be rather costly, and take lots of time for preparing and eating.