FIFA’s Chief Medical Officer, Professor Jiri Dvorak, sat down for an interview with FIFA.com to discuss the myths, realities and dangers of food supplements among athletes.

FIFA.com:
According to recent studies, can you tell us how widespread the use of food supplements is among footballers?
Professor Jiri Dvorak: Based upon the data which we’ve collected since 1998 during FIFA competitions, it is quite surprising that at World Cup level - and we have very sound data from 2002, 2006 and 2010 - around 35 per cent of all players are regularly taking food supplements. But the more surprising fact is that almost 50 per cent of the U-17 and U-20 players at World Cup level are also taking food supplements.

Why are they using them so much? Do they believe it will help their performance?
Yes, definitely. The marketing strategies of the producers of food supplements are influencing the behaviour of footballers and athletes in general. From different surveys we know that about 60 per cent of U-16 athletes in the USA are using nutritional supplements daily and all of them believe they will increase their performance. This is definitely not based upon the scientific evidence or literature, which says the opposite, that any of the food supplements, except in certain medical conditions, will improve your performance.

The same scientific studies also show that 70 per cent of these young athletes do not seek adequate advice from a nutritional specialist physician, they just take it and believe it will improve their performance. For me as a sports physician this is not only surprising, it is alarming! Scientists and nutritional specialists agree that a well-balanced diet will supply the body with the appropriate amount of nutrients it needs for top performance.

What are the medical dangers of using food supplements?
For food supplements to be approved by official authorities in different countries, such as the FDA in the United States, the content of the supplements must be declared. However, most of dietary supplements are not subject to quality control and therefore not obliged to disclose the full content.

It is well established and proven that many of the food supplements are contaminated by prohibited substances such as anabolic steroids and other substances. This is, of course, very dangerous because if the athlete is subject to a doping control test and is regularly using that kind of contaminated supplement, he or she can test positive for doping. Therefore, FIFA has issued a serious warning to football players not to take any food supplements that have not been passed by national drug and food administrations.

This is a highly controversial issue and we would more than welcome the food and drug administrations in different countries to carefully subject food supplements to quality control in order to avoid contaminated supplements. Unfortunately, it was also reported that some meat products in different countries, such as Mexico and China, have contained anabolic steroids, and this could also be found during the urine doping controls.