Heavy consumption of the essential amino acid lysine (as indicated in the treatment of cold sores) has allegedly shown false positives in some and was cited by American shotputter C. J. Hunter as the reason for his positive test, though in 2004 he admitted to a federal grand jury that he had injected nandrolone.  A possible cause of incorrect urine test results is the presence of metabolites from other AAS, though modern urinalysis can usually determine the exact steroid used by analyzing the ratio of the two remaining nandrolone metabolites. As a result of the numerous overturned verdicts, the testing procedure was reviewed by UK Sport . On October 5, 2007, three-time Olympic gold medalist for track and field Marion Jones admitted to use of the drug, and was sentenced to six months in jail for lying to a federal grand jury in 2000. 
HCG is a highly beneficial hormone in fertility stimulation and in the treatment of low testosterone. In fact, it is rapidly becoming an integral part of many low testosterone treatment plans. For the anabolic steroid user, the performance enhancing athlete, HCG can be beneficial but it can also be damaging. Many get very carried away with on cycle use and lead themselves to an early low testosterone condition. Granted, most men will benefit from testosterone therapy at some point in their life regardless, but many steroid users end up requiring sooner and often due to improper HCG use. The hormone can be beneficial but use must be kept moderate and monitored.