A recent study in the Journal of the International Society of Sports Nutrition found that a majority of athletes are fairly clueless when it comes to making wise choices with respect to supplementation for sports performance.

European investigators recruited 912 male and female pro athletes from four Olympic disciplines—soccer, volleyball, handball and basketball—and then gave the players questionnaires designed to suss out their subjective knowledge (how much they thought they knew) and objective knowledge (how much they actually knew) with respect to nutrition and supplementation. Results showed there was a poor correlation between subjective and objective knowledge.

For instance, some athletes who ranked their nutrition and supplementation know-how as being high (subjective) answered several objective true-or-false questions like “Large chains of amino acids form carbohydrates” incorrectly. A significant number of study subjects also declared “self-education”—not nutrition professionals—as a primary source of nutrition and supplement information. Since supplementation usage among athletes is high across the board, this education disconnect could lead to the use of pills and powders that, at best, are useless and, at worst, could harm performance or health.

The researchers called for more education and monitoring by coaches to help ensure that athletes make appropriate decisions on supplement use and diet. As a fitness professional, you can also help. You may not be qualified to dish out nutrition advice, but you can refer clients to a dietitian when needed.