Rough edged question but the answer really is yes AND no. There is a lot of garbage out there but there is, and has been for some time, some that make a difference. The thing with supplementaion is that it is to supplement what you aren’t getting enough of to enhance your performance. Overdosing is a big waste and often dangerous even in the most scientifically proven supplements (ex. creatine & fish oil.) I take a lot of vitamin C but that is for ME as its something that I personally need for improved performance. If someone is deficient in a vitamin or mineral then its best that their dietician recommend them to the proper source.