At a time when world standards in sport are moving to ever-higher levels, and training programmes are becoming ever-more demanding, the athlete who wants to make it to the top – and stay there – must explore all possible means of securing an advantage. Nutrition offers one obvious way to get ahead.

A varied diet, consumed in quantities sufficient to meet the energy needs of the athlete in training, should provide all the essential nutrients in adequate amounts. But not all athletes eat a varied diet, and total food intake may at times be restricted, which can lead to deficiencies of some nutrients. Because these deficiencies may be difficult to detect in their early stages, athletes are often tempted to take individual nutrients in a concentrated form as a precaution. And an enormous multinational industry has grown up to cater for this demand.

However, athletes should take supplements only after balancing the potential rewards against the very real risks. For although vitamin and mineral supplements are perceived as harmless, and the daily multivitamin is regarded as an insurance policy, supplements are not always benign.

Routine iron supplementation, for example, can do more harm than good, and the risk of toxicity is very real. It has been estimated that, in industrialised countries, twice as many men suffer from iron overload due to excessive use of supplements than from iron deficiency.

But there are other risks associated with taking supplements – risks that are less physically threatening but may be more difficult to reverse.

More exotic supplements, many of which have names – and promotional material – that suggest an anabolic action, have become a prominent feature on the shelves of sports nutrition stores in the last decade or two. Some of these products make extravagant claims about building bigger, stronger and faster muscles, repairing the damage caused by hard training, resisting infections and illnesses, and preventing chronic fatigue. They usually come with fancy price tags, but for the athlete who is training to the limits no price seems too high.

This may be true in a strictly financial sense but, if we are to believe some of our top athletes, they have paid a far higher price in recent years. Being labelled a drug cheat is something no athlete wants and no innocent athlete deserves. Every effort must be made to ensure that athletes who use illegal drugs to enhance performance are caught and punished but, at the same time, the innocent must be protected.

Which brings us to the thorny issue of Nandrolone in sport. Nandrolone is the popular name for the anabolic androgenic steroid more properly known as 19-nortestosterone. Many different androgenic anabolic steroids, including nandrolone and testosterone itself, have been used by athletes over the years, and well-established measures are in place to detect abuse.

The apparent spate of nandrolone cases in British athletics over the last couple of years has cast a shadow over the sport as well as the individuals involved. Dougie Walker, Linford Christie and Mark Richardson are among the top athletes from various countries who have produced positive tests for nandrolone, although Walker continues to protest his innocence even after completing the two-year suspension from competition that effectively ended his career, and the others also vigorously deny any wrongdoing.

This problem is not unique, either to athletics or the UK. Football, boxing, cycling, rugby, weightlifting and many other sports have seen similar cases. Nonetheless, UK Athletics has taken the lead in investigating the possible reasons for the positives.

Were the athletes cheating?

The problem was approached with an open mind, and all possibilities were considered, including the possibility of deliberate and systematic cheating by the athletes concerned. A review of the positive cases within athletics revealed that all of the athletes had reported using a range of dietary supplements, mostly from the same supplier.

A study carried out at Aberdeen University showed that administration of these supplements to athletes and to healthy volunteers training at a more modest level resulted in some positive tests. And those who tested positive recorded concentrations of 19-norandrosterone (the nandrolone metabolite whose presence is taken as evidence of nandrolone in the system) of up to about 30ng per ml of urine: anything above 2ng/ml and 5ng/ml for females counts as a positive.

Initial analysis of the supplements taken by the athletes and volunteers did not detect nandrolone or any other related steroids that could explain these positive tests. The International Athletic Federation (IAF) did not accept these results, which were, in truth, difficult to explain. But, because of the time pressures, it was not possible for the researchers to test a large number of supplements or a large number of athletes before presenting these data to the IAF.

However, when the analysis of some of the dietary supplements was repeated, using an improved method developed by the IOC-accredited laboratory in Cologne, the Aberdeen and Cologne laboratories both found tiny amounts of a number of different steroids in several of these supplements. The amounts of steroids, although sufficient to play havoc with the careers of these athletes, were far too small to have any beneficial effects on performance. The supplements did not say on the label that they contained any banned substances and the athletes involved believed them to be suitable for use.

At about the same time as these results were coming out of Aberdeen, similar findings were reported from IOC-accredited drug testing laboratories in Germany, Canada and the USA. In Italy, two athletes tested positive after taking iron tablets, and nandrolone precursors were later found to be present in some of the tablets. In Germany, nandrolone has been found in creatine powder sold to athletes.

Strict liability still applies

There is now a considerable weight of evidence to show that not all dietary supplements can be regarded as safe, even when the label or promotional material says they are. As before, however, the principle of strict liability applies (meaning that the athlete is responsible for whatever is in his or her body, irrespective of how it got there) and athletes who test positive in these circumstances are technically guilty.

Dietary supplements are not evaluated by regulatory agencies, and inaccurate labelling of ingredients is known to be a problem. Most supplements, it has to be said, will not cause problems for the athlete, and most companies that manufacture and supply these supplements are anxious to ensure the welfare of their customers. Nonetheless, the supplements reported to have been used by athletes who gave positive tests, backed up by the Aberdeen research, were all apparently innocuous substances, which should not have resulted in positive tests, even in the high doses used by some of these athletes. Until the picture is clarified, the only safe course for prudent athletes would seem to be to avoid anything that cannot be absolutely trusted.

An authoritative paper published in the scientific literature in November 2000 provided some of the first solid evidence of steroid contamination of dietary supplements.

This study reported the results of analysis of three legitimate dietary supplements – Chrysin, Tribulus Terrestris and Guarana – none of which declared on the label that they contained steroids or might reasonably have been expected to do so. The researchers found nandrolone, testosterone and other steroids in these supplements: when they were fed to healthy volunteers, they gave positive nandrolone urine tests, with urinary concentrations of up to 360ng/ml (remember, the threshold for a positive test is 2ng/ml for men and 5ng/ml for women).

The Cologne laboratory followed up with a much bigger study of 634 different product samples from 215 different suppliers in 13 countries around the world. The samples were analysed for the presence of steroid hormones and their precursors, and 94 supplements (14.8% of the total) were shown definitely to contain prohibited substances. In another 66 samples (10.4% of the total), the analysis was inconclusive, but steroids may have been present. Substantial numbers of positive tests were obtained from products bought in The Netherlands (26% of 31 products tested), Austria (23%), the USA (19%), UK (also 19%) and elsewhere.

The supplements which produced positive results have not been identified, but they included vitamins and minerals, protein supplements, creatine and many others. It was interesting to note that 21% of products from companies selling prohormones (substances converted in the body into active hormones) tested positive, while only 10% of samples from companies that did not sell prohormones were positive.

The IOC-accredited laboratory in Vienna has repeated the Cologne study, albeit with a smaller number (54) of supplements. They found that 12 of these (22%) contained prohibited steroids – almost the same proportion as the Cologne lab found for supplements bought in Austria. Unlike the German results, the identities of the companies and their products have been published on the Internet, and can also be found on the Cologne website at.

Events took a more sinister turn in 2002, when the laboratories in Cologne and in Vienna found one of the ‘hard’ anabolic steroids (methanedieneone) in a supplement purchased in England. This drug was present in high enough amounts not just to have an anabolic effect but also to produce serious side effects. The presence of this steroid has been described as a ‘deliberate and criminal act (remember that this was the drug that caused problems for British athletes Janine Whitlock and Perris Wilkins).

So where are we now? In some ways it does not help to know what was positive last year because the market keeps changing, with old products disappearing and new ones appearing on a regular basis. It is also true that products from the same batch – or even the same bottle – may be either clean or contaminated.

In a future article, we will look at some of the steps athletes can take to protect themselves and at some of the proposed legislation changes that might make the supplement industry more accountable than at present.

Ron Maughan