Is Nährstoffcheck useful for Sport?

A nutrient check (e.g., blood test for vitamins, minerals) can be useful for athletes to identify deficiencies that may impair performance or recovery – such as iron, vitamin D, or magnesium. However, the evidence is mixed: for asymptomatic recreational athletes, routine screening generally shows no clear benefit, while targeted testing in elite athletes with specific symptoms can be justified. The evidence base is mostly observational (human-moderate), not from randomized controlled trials. Results can also fluctuate due to recent diet, training status, and lab variability. A nutrient check should not replace medical advice or be the sole basis for supplementation – high doses of certain nutrients (e.g., vitamin B6, iron) can be harmful.