Supplements and their risks
Diet is something athletes are concerned about as they seek to improve their performance or possibly lose weight, gain muscle or increase endurance. They may ask you as a medical professional for advice on the best diet for training or performance.
Athletes may also discuss the use of supplements, including vitamins and minerals.
Drug Free Sport NZ advises athletes to be wary about taking dietary or sports supplements because supplements could contain substances which are banned in sport. Many supplement manufacturers also lack adequate quality control nor do they accurately label ingredients so you cannot be sure of exactly what’s in them.
A recent UK study of supplements chosen because they appeared to contain anabolic agents due to the name of the product, the ingredients listed, or the nature of their advertising found that 23 of the 24 products tested contained anabolic steroids. An earlier study funded by the International Olympic Committee (IOC) in 2001 of nutritional supplements found that of the 600-plus supplements tested, around 15 per cent contained steroids or related compounds which were not listed on the label.
A significant number of Drug Free Sport NZ’s positive tests in recent years have been as a result of prohibited substances found in supplements so it’s important that athletes are aware of the risks they take if they consume these products.
You can help athletes who are tempted to take supplements by encouraging them to focus on diet and nutrition instead. The following resources may be helpful:
- the Olympic Committee’s Medical Commission’s Nutrition for Athletes
- The United States Anti-Doping Agency’s Nutrition Guide
- NZ’s Millennium Institute of Sport and Health and Nestlé have put together a collection of nutrition advice sheets for specific sports.
If an athlete does decide to take supplements, encourage them to gather as much information about the supplement they intend to take as possible.
Athletes take any supplement at their own risk and Drug Free Sport NZ cannot guarantee any supplement, but you can check the risks associated some of the more common products available in New Zealand here.