May 2018, Articles

Choosing Dietary Supplements

Why athletes should choose dietary supplements carefully

What is a dietary supplement?

Although dietary supplements are regulated in most countries, there is usually no pre-approval (unlike a medicine) required before being sold.  This means some products enter the market without being adequately tested by the manufacturer for safety, purity and if it actually does what it claims to do. Harmful ingredients, incorrectly labelled, and contaminated products are often only discovered after the product has been ingested by athletes and consumers.

Discovering that a product may not contain what an athlete thinks, could be too late.  A recent study found up to 1 in 5 dietary supplements are contaminated, either intentionally or through poor manufacturing, with substances that are on the World Anti-Doping Agency (WADA) Prohibited list. Contaminated supplements have been associated with positive drug tests in athletes and it is important to know the rules and responsibilities as an athlete, parent, coach or sport support person.  No supplements are approved by WADA or Drug Free Sport New Zealand (DFSNZ).  Access the DFSNZ e-learning resource here.

In New Zealand, dietary supplement ingredients and products can be sourced, manufactured and accessed worldwide (e.g. internet) and may be subject to the dietary supplement regulations in the country of manufacturing. Regulations differ worldwide.

Dietary supplements may cause adverse effects and be contraindicated for some athletes (e.g. food allergies and medical conditions). Product specific information is not always clear and/or adequate. For in depth information about ingredients used in supplements look here.

Dietary supplements in New Zealand are regulated under the Dietary Supplements Regulations 1985, which falls under the Food Act 2014.  While dietary supplements are regulated, they may still contain WADA prohibited substances.


Choosing batch tested product

Choosing a dietary supplement that has been independently batch tested substantially reduces the risk for consuming a product contaminated with substances banned in sport.  The testing is sensitive and can detect even tiny amounts of contaminants in a supplement but is never a 100% guarantee of purity or safety. Contamination can occur in one batch and not another so HPSNZ advises athletes that any product used should have a batch certificate that exactly matches the product. Accredited and independent batch testing services are available worldwide and these logos can usually be found on products that indicate they have been tested. Each service differs in the frequency of product testing and WADA Prohibited substances analysed. See logo links for further details.

Once a product passes batch testing, a Certificate of Analysis (COA) or the batch number is usually made publicly available on these websites or to the manufacturer to prove that the batch has been tested and passed.  Athletes should always check their product has been independently batch tested as this is their responsibility. Contact the manufacturer if you cannot find the batch number or certificate.  Remember neither WADA, the International Olympic Committee (IOC) or DFSNZ approve any supplements for safety.

How to find the batch number on a product?

A product batch (or Lot) number is often located next to the expiry date on the bottom of a container, or on the lid.

For example:

Supplement contamination alerts can be found here