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Are Your Supplements Safe?

Supplements are becoming a growing trend amongst athletes. A recent research study into supplement use within UK high performing athletes showed that of the 874 athletes participating in the study, approximately 60% of these athletes used at least one nutritional supplement. But the question I would like to pose is just how safe are some of these products?

For those of you that are regular readers of my blogs, you will know that out of preference, and wherever possible, I like to promote a ‘food first’ approach to the athletes that I work with. There are 2 main reasons I do this:

(1) It helps promote an element of sustainability to any nutritional strategy, as let’s face it – we ALL need food!

(2) It dramatically reduces the risk of potentially producing a positive drugs test from a supplement that might (and I stress the word “might”!) be contaminated with a banned or illegal substance.

I am not alone in this point of view. Performance nutritionists who work for sporting agencies and the sporting agencies themselves, such as the English & Australian Institute of Sports (EIS & AIS respectively), also share this philosophy.

Now, I would just like to say that this is not an attack on the sports supplement industry! Before I get every supplement manufacturer hunting me down and wanting to string me up, reputable sports supplement companies do not intentionally add banned substances to their products! They are certainly becoming more stringent about their products, however research has shown the problem does exist.

Several studies have highlighted that nutritional supplements may contain undeclared substances that are banned by the International Olympic Committee (IOC)/World Anti-Doping Agency (WADA).

For example, a study conducted throughout the UK market and published in 2007 found that of 64 supplements tested, approx. 12.5% of these contained levels of banned substances that were not declared on the label.

An international study carried out between 2001/02 on 634 nutritional supplements, purchased in 13 different countries, showed that about 15% of the non-hormonal nutritional supplements were contaminated with anabolic steroids.

Since 2002, products with high amounts of ‘classic’ anabolic steroids have been detected on the nutritional supplement market. These anabolic steroids were not declared on the labels of the products. The brand names of the products that were found to be contaminated were not named in the study, however amino acid and protein powder supplements were included, with the steroid concentrations ranging from 0.01µg to 190µg per gram of product.

Case Study:

I like to use the following as an example as it shows that contamination of supplements can even happen at the highest levels of the game!

Ex-Sale Sharks Prop, Karena Whiongi received a 4-month ban for producing a positive drugs test for the banned substance Methylhexaneamine (MHA) post-match against Newcastle Falcons in 2011.

After some investigation, it turns out he had ACCIDENTALLY drank the sports supplement product at half-time – he mistakenly drank from the wrong bottle, which could happen to anyone! Despite the product having a certificate to give it the ‘all-clear’ in terms of banned substances it still gave a positive drugs test – so this demonstrates that there are no safety guarantees with supplements!

How to make sure your supplements are safe

Most (if not all) top-level clubs, when receiving their sports supplements, request that the products are ‘batch-tested’. This is essentially where the product is tested to make sure it contains no banned or illegal substances. HOWEVER – this is no guarantee! As demonstrated in the case study above, Sale Sharks had a batch-test certificate for their product!

In addition, there is a great website available – which acts as a quality assurance programme for sports nutrition supplements. If you are concerned about your supplements, it allows you to see which companies are registered and which of their products (under the ‘Registered Products’ section) have been shown to contain no banned or illegal substances. Please do check that part of the site out!


I don’t want it to come across as though I am bad-mouthing the sports supplements market because I’m really not! My job is to make sure that athletes not only have correct nutritional practices and education in place, but also that what they are doing is ultimately safe. Banned substances can (not always do!) appear in sports supplements, and as such it is my responsibility as a performance nutritionist to make an athletes aware of the potential risks involved.

I totally accept and agree that sports supplements do have their place within sports nutrition. I use a small-handful of products with the athletes I work with – all backed up by research and batch-testing certificates, which is the best we can do at this time.

Supplements can often be convenient, particularly during heavy training phases or where time between sessions is limited, however, they need to be safe for the athlete too. Which is why, and I’ll keep saying it, a ‘food first’ approach is the best way to combat any potential risks.

Any thoughts or comments are welcomed on the subject. Please leave comments below.

Twitter: @nutrition_total

About ccurtis

Sports Nutritionist - who writes a monthly Rugby Nutrition blog for FindRugbyNow. Also at the moment work alongside West Ham FC Academy, have previously worked for Saracens, Newcastle Falcons and the RFU & England Rugby team Nutritionist. In addition, I run my own company (Total Nutrition Ltd.) that works alongside NHS/public health/education sectors educating communities (both children & adults) about the importance of nutrition. View all posts by ccurtis

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