Hidden doping traps

To avoid falling into the hidden doping trap through naive eating habits or careless everyday behaviour, athletes should be aware at all times that they have to face the consequences of testing positive, regardless of whether or not they are aware of the offence.


Risks of unintentional doping

Food supplements

Food supplements are substances that enhance the overall diet and have a specific dietary or physiological effect. They include vitamins, minerals, trace elements, amino acids and proteins, as well as fibre, plant and herb extracts. There is a vast array of food supplements and many athletes take them, particularly at elite level, to meet their greater need for energy and nutrients.


They are generally taken in the form of tablets, liquids, capsules or powder. However, they are foodstuffs that enhance the daily diet, not drugs or medication, and athletes who must abide by anti-doping rules need to be particularly careful, as using food supplements can result in unknowingly and unintentionally failing doping tests. It is not uncommon for such supplements to become contaminated with doping-relevant substances, whether through the filling process, substances not listed on the packaging or simply deliberate manipulation. In addition, the manufacturing criteria are very different to those of drugs – it is impossible to be completely sure. According to WADA, an increasing number of products contain banned substances such as steroids or their precursors. The consequences can be serious: taking contaminated food supplements can lead to positive urine samples, which constitutes doping in accordance with the principle of strict liability as applied in the anti-doping rules. 

Before the athlete takes such a supplement, the latter must have been tested by an independent institution for the presence of a prohibited substance. A declaration by the manufacturer as to the product’s purity should be a minimum requirement for every athlete. Although these steps can reduce the doping risk where food supplements are concerned, athletes should not lose sight of their responsibilities or of the potential consequences.


An international study commissioned by the IOC and conducted by the Institute of Biochemistry at the German Sport University in Cologne found that around 15% of the food supplements acquired in 13 countries contained anabolics (mainly prohormones), which were not listed on the packaging. Anabolics concern mainly contaminants that do not have a doping effect but can lead to an unintentional positive doping test. A similar study in Austria supported the results. The Institute of Biochemistry at the German Sport University in Cologne is currently conducting a follow-up study on behalf of WADA.

DEFINITION of food supplement:

In EU law, food supplements are regulated by the 2002/46/EG directive, which includes the permitted minerals and vitamins. In the Nahrungsergänzungsmittelverordnung (Food Supplements Regulations), which are based on the above directive, a food supplement is defined as

“any food the purpose of which is to supplement the normal diet and which is a concentrated source of a vitamin or mineral or other substance with a nutritional or physiological effect, alone or in combination and is sold in dose form, which means in the form of capsules, pastilles, tablets, pills and other similar forms, sachets of powder, ampoules of liquids, drop dispensing bottles, and other similar forms of liquids or powders designed to be taken in measured small unit quantities.“


There are drugs, medications and homeopathic remedies that every athlete can buy without a prescription, e.g. from a chemist’s, and, it would seem, take with a clear conscience. However, this is not the case: even medication that seems at first glance to be harmless may contain substances that violate anti-doping rules. Better safe than sorry: athletes should consult their doctor before taking medication if suffering from a cold, a slight headache, nausea or allergies. That is the only way to be sure of avoiding doping.


The consumption of cannabis outside sporting competitions is not banned in every country. Moreover, cannabinoids (marijuana, hashish) do not necessarily improve performance, especially in competitive sport, because cannabis has a relaxing effect, thus reducing sporting ambition. Nevertheless, cannabis is prohibited during competition as its calming effect and alteration of the perception serve to lower inhibition to the extent that the athlete is prepared to take greater risks.


WADA has set the threshold for THC carboxylic acid at 150 nanograms per millilitre. As cannabis is only banned on the day of the competition, this threshold is sufficient to prove the doping-relevant use of THC on the day concerned. However, consuming cannabis in one’s leisure time also poses a big doping risk because the body stores tetrahydrocannabinol (THC), which can be detected for weeks afterwards.

Everyday food

Consuming normal food and drink can also result in a positive test if they contain banned substances. The most well-known example is the poppy, the seeds of which contain morphine, a substance on WADA’s prohibited list. Depending on the poppy seeds and the amount involved, an increased concentration of morphine can, in extreme cases, ensue and thus lead to a positive doping test.

Asian herbal teas are another example: ephedra is a medicinal plant that is used to counteract colds in traditional Chinese medicine, but it can result in a positive test as this stimulant is also prohibited.