Supplements are a risk for all athletes. We know many athletes nonetheless choose to use supplements

If that’s you, it’s important to make an informed decision. This Guide can help by showing you ways to minimise – but not eliminate – supplement risks. 

Remember, athletes can and do test positive as a result of contaminated supplements. Athletes are 100% responsible for anything found in their sample. 

• Have you received expert advice (e.g. registered nutritionist, dietician, GP, sports doctor) on your individual nutritional needs, your nutrient timing around exercise and/or your fuelling requirements? 

• Can you get the nutrients you need from food (i.e. without using a supplement)? 

• Could a more balanced schedule, with appropriate levels of training, recovery or study, help you achieve your goals? 

• The safest option is a food-first approach to nutrition. 

• When you seek expert advice, tell them you are an athlete who could be tested at any time. 

• Supplements are manufactured in factories, and not medical labs. This increases the risk of cross-contamination. because supplements are regulated differently to foods and medications.

• Inaccurate labelling, whether deliberate or accidental, makes it difficult to know what’s really in supplement products. 

• A Consumer NZ investigation found illegal drugs and/or banned substances in six supplements bought from NZ supplement stores.

• Supplements can contain WADA-banned substances.

• Athlete can and do test positive as a result of contaminated supplements.

• Is there evidence from expert sources supporting the effectiveness of the supplement?

• Does the supplement's claimed benefits seem too good to be true?  

• Be sceptical of claims, or influencers, telling you that a product works. What is their motivation? 

•  Supplement safety and effectiveness is rarely proven in athletes under 18.

• There is a lot of misinformation on social media.

• Are any of the supplement’s ingredients on the current WADA Prohibited List? 

• Using different supplements with similar ingredients may lead to exceeding the safe upper limit for certain micronutrients, which could be detrimental to your heath.

• Have you consulted your support team (e.g. registered nutritionist, dietician, GP, sports doctor) about potential supplement side effects and discussed any other medications or supplements you're using? 

• Supplements can contain substances that are prohibited in sport - and they may not be listed on the label.  

• Using incorrect doses, or thinking ‘more is better’, is dangerous for your health. 

• Words like ‘herbal’ or ‘natural’ do not necessarily mean it is safe. 

• Due to different chemical names for the same ingredient and proprietary blends, it can be difficult to identify WADA-banned substances on the label for an untrained (and sometimes trained) eye.

• Has the supplement been batch tested for banned substances by a well-established third-party programme? 

• Have you read High-Performance Sport NZ’s advice on batch testing?  

• Do the batch number and expiry date on the supplement packaging exactly match the batch testing certificate? 

• Batch testing doesn’t mean you can be 100% sure that a product has no banned substances, but it does mean you can have increased confidence in a specific batch. 

• Check if the seal, pack and cap of the supplement is intact prior to using the product

• Is this your own supplement, and not shared with you by another person? 

• Have you kept a record of the supplement’s batch number and expiry date? 

• Do you have a plan for reviewing your supplement use, taking into account all factors outlined in this Guide? 

• If tested, remember to list all substances you have used on your doping control documentation.  

• By taking supplements, you risk testing positive for a prohibited substance. 

• Athletes are 100% responsible for anything found in their sample. 

Neither the Commission nor WADA approve any supplements or their use.

If you NEED to use a supplement (e.g. if test results have found you lack a nutrient), it’s important to get advice from an expert (e.g. registered nutritionist, dietitian, GP, sports doctor) before you start taking any supplements.