Supplements are one of the advantages that an athlete can take. In the USA, we are fortunate to have high quality and relatively cheap assortment of supplements. Having traveled to countries like Colombia, Bulgaria, Germany, Poland, or Romania, I can tell you that high quality supplements are very expensive and more difficult to find.
Here’s an example: Protein intake for an athlete is reccommended in ranges from .8g/kg bodyweight to 2g/kg bodyweight. Now, if your goal is to get stronger and recover, but not gain weight, protein powders are one of the best ways to accomplish this. How else can you get 25grams of protein crammed into a 150 calorie, delicious shake.
Finally, many of us are in USOC/USADA no advance notice drug testing or compete at drug tested events;ofcourse, one has to take supplements at their own risk. Feel free to check with manufacturers on ingredients. Still, as a business person, what incentives does a manufacturer have to put banned substances into low-carb whey proteins or fruit and nut bars?
They don’t have any advantage of putting banned substances in but they do have poor practices of manufacturing the supplements. Up to 20% of all supplements are contaminated. That is to much of a risk.
Please reference your research.