Kansas State University Human Nutritionist Brian Lindshield researches supplements to see if they contain what's on the label.
He says you aren't always buying what you think.
"It will prevent deficiency, but it's not going to make up for a lot of the chronic disease risks and those sorts of things," said Lindshield.
The FDA doesn't regulate supplements the same way they regulate drugs so the claims of health benefits or weight loss aren't always proven.
Lindshield says If you are purchasing supplements pay close attention to the label.
He says the more descriptive the label, the better.
And while you may not want to pay more for your supplements, you'll probably get a better product.
"Probably don't buy the cheapest one available because if they are cutting corners to get their price really cheap, they probably are not going through the same amount of standards that the more expensive ones are," he said.
Some supplements are true to their word.
Lindshield's research found that supplements that may prevent prostate cancer did contain the ingredients they claimed.
Click here for a resource guide on supplements.