Many athletes believe that the demands of competing at an elite level require the use dietary or nutritional supplements. While the IOC’s Nutrition Working Group would agree that an athlete with a demonstrated deficiency of an essential vitamin or mineral may benefit from the use of supplements where it is not possible to consume enough food to compensate for the deficiency, the use of supplements does not compensate for poor food choices or an inadequate diet.


  • There’s an alarming increase in the number of supplements resulting in harmful side-effects (medical problems and fatalities) as well as positive drug tests in youth and adults alike (locally and globally).
  • There is a lack of legislation and governance in the supplement industry locally and abroad – products can be advertised and sold with misleading claims, incorrect labeling, and lack of scientific-grade evidence of efficacy and safety. Despite the marketing hype and product claims, the fact remains that the majority of supplements on the market have not been tested according to proper scientific and objective standards, and their claims of superiority, efficacy and safety cannot be guaranteed.
  • Be aware that supplement manufacturers and retailers (including pharmacies) may indeed claim that their product is ‘scientifically tested’ or ‘safe’, but at closer inspection the evidence may be insufficient, irrelevant, misinterpreted, not applicable to youth, or in the worst, fabricated.
  • Claims that the product is ‘natural’ or ‘herbal’ does not necessarily mean that it is harmless and cannot get you banned.
  • Many herbal components can have potent harmful side-effects, can lead to harmful interactions with other herbals or medications, and/or lead to a failed drug test.
  • Vitamins, minerals, anti-oxidants (and other nutrients) from supplements can more easily reach levels that exceed safety limits, which can cause negative health effects and block important training adaptations that will negatively affect athletes’ sporting performance.
    • Examples:  Large doses of Vitamin C (>2g/day) have not only been shown to block important training adaptations and reduce performance, but also increase muscle damage and delay recovery;
    • Large doses of anti-oxidants can block some of the health-enhancing effects of exercise; and have been linked to increased risk of certain cancers and a negative impact on cardiovascular health.
    • Certain vitamins/ minerals in excess can impair immune function; limit the function (and beneficial effects) of others.
  • Reliance on supplements shifts focus away from the more important and proven methods of achieving optimal performance and health.

Industry Claims on Supplements

A major concern with the supplement industry is that they do not have to follow the same good manufacturing practices (GMP) as pharmaceuticals, and manufactures are not required to display the entire ingredient list on the packing of substances.  Many supplements that are advertised as muscle builders and fat burners are known to contain a prohibited substance. Those that claim to increase energy, including those that claim to be natural or herbal, are not likely to improve performance and not supported by research.

In fact, most supplement manufactures claim that their products are backed by valid scientific research, which is not the case. Furthermore, there is no strong scientific evidence to support the claims that supplements such as glutamine, zinc, Echinacea, and colostrum, can provide a boost

the immune system.


These poor GMP and labelling practices can put an athlete subject to doping control at risk of committing an anti-doping rule violation (ADRV). While the risk may be higher with supplements sold on the black market or on the Internet, those sold in shops labelled herbal or natural may also be contaminated.

Due to the principle of strict liability in the World Anti-Doping Code (Code), an ADRV associated with the consumption of a contaminated supplement, whether it is due to poor labelling or contamination during the manufacturing process, is responsible and will be sanctioned. While this sanction may be reduced if the athlete can prove that the adverse analytical finding (AAF) was due to the use of a poorly labelled or contaminated supplement, the athlete is not dissolved of all responsibility. The contamination of substances and the lack of scientific research can also put the health of those consuming the supplements at risk. Many athletes fail tests because of the supplement products they use.

The risks with supplements are:

  • Supplements can contain banned substances;
  • Supplements can be contaminated with banned substances during the manufacturing process;
  • Supplements may contain ingredients listed differently to how they appear on the Prohibited List;
  • Be wary of fake supplement products, especially when buying over the internet;
  • There is no guarantee that any supplement product is free from banned substances;

Managing the Risk of Supplement

There are no guarantees that any supplement product is free from banned substances.

  • Athletes must be fully aware of the risks to their career if they chose to use a supplement product.
  • All athletes must undertake thorough internet research prior to using any supplement product. This is a WAD Code requirement.
  • Not knowing is not an excuse. If you test positive, it will be for you to prove how the banned substance entered your system.
  • The World Anti-Doping Code and ETH-NADO Rule makes a provision for contaminated products (supplements), so make sure you can prove that you have taken all steps to manage the risks associated with supplement use.

ETH-NADO Advice about supplements

If you need to use supplements, you should do the followings before you take it.

  1. Assess the need: seek advice from a qualified medical professional to determine whether you need to use a supplement.
  2. Assess the risks: only use batch-tested supplement products to minimize your risks of contamination.
  3. Assess the consequences: to your career prior to using any supplement product. You could receive a four-year ban.
  4. Use batch-tested products: If you still chose to use a supplement product, you need to use a batch-tested product. Make sure you check the actual batch numbers prior to use.

An important principle of the World Anti-Doping Code and ETH-NADO Rule is that of strict liability, which states that athletes are solely responsible for any prohibited substances they use, attempt to use or is found in their system regardless of how it got there and if there was an intention to cheat. Before taking supplements, athletes must therefore assess the need, risk and consequences to their careers.

Diet, lifestyle and training should all be optimized before athletes consider supplements and they should always consult a medical professional or nutritionist and seek advice.

Supplements may claim to be drug-free or safe for drug-tested athletes. It is not possible to guarantee that specific supplements will be free of prohibited substances and athletes can only reduce the risk of inadvertent doping by making informed decisions.

There is an array of supplements available for athletes to purchase that have no prohibited substances listed as ingredients. Despite this, there have been several cases whereby supplement products have been contaminated with prohibited substances as defined by the World Anti-Doping Code (the Code) Prohibited List.


  • Optimizing one’s training, overall dietary intake, rest, recovery and sleep patterns are proven to have a far bigger impact on physique, performance and health than any sport supplement (or ingredient or formulation) tested to date can.
  • ‘Skimping out’ on any of the important aspects of nutrition and training cannot be replaced by the use of supplements.
  • Nutrients from supplements are not better than those you get from food, especially to build muscle, reduce body fat, enhance recovery, immune function and maintain overall health and performance short- and long-term.
  • A well-balanced diet can boost performance and eliminates the many risks that one faces when using supplements.
  • There are only a small number of supplement ingredients proven to assist exercise performance under certain specific conditions, mainly in adults, but even so, it is NOT a one-size-fits-all approach and one still cannot guarantee that it is 100% safe and risk-free, especially in youth.
  • Supplements are expensive – rather invest time and money in seeing a registered dietitian, who specializes in sports nutrition. This would be the best person to devise an individualized sport nutrition programmer for you and, where appropriate, guide you on the correct use of supplements and how to minimize risks.