Potential Impact on Insulin Sensitivity

Anabolic/androgenic steroids (AAS) can alter insulin sensitivity, a critical factor in metabolic health. However, the effects of these drugs can vary. For instance, testosterone administration may improve insulin sensitivity in men with hypogonadism. Oxandrolone (20 mg/day) has also shown improvements in insulin sensitivity in elderly men (ages 60 to 87). These beneficial metabolic effects are associated with reductions in visceral adipose tissue (VAT), which is the deep fat surrounding abdominal organs and is linked to insulin resistance. Insulin resistance can lead to other health problems, including hypertension, elevated triglycerides and cholesterol, as well as increased risks of diabetes and cardiovascular disease. By reducing VAT levels, testosterone and AAS may enhance insulin sensitivity and potentially improve metabolic health.

Conversely, the abuse of anabolic/androgenic steroids has been linked to disruptions in glucose metabolism. In one study, long-term abuse of high doses (up to seven years) resulted in reduced glucose tolerance and increased insulin resistance. Despite a long history of endurance exercise, these subjects secreted more insulin during glucose intake measurements compared to obese controls. Other studies on oxymetholone have indicated significant increases in insulin secretion and potential resistance. However, not all AAS studies have reported similar findings. For example,

 administering up to 600 mg of testosterone enanthate weekly for 20 weeks did not produce any changes in insulin sensitivity among healthy young men. Nandrolone decanoate (300 mg per week) also did not impair glucose tolerance and actually improved insulin-independent glucose handling.

The data on the effects of anabolic/androgenic steroids on insulin sensitivity are challenging to interpret. When these drugs are initially used,

 reductions in body fat, particularly visceral fat tissue, are evident. This can actually improve insulin sensitivity and overall metabolic status, reducing specific risk factors for diabetes and cardiovascular disease. Beyond this, the effects of AAS on glucose metabolism are not well understood and difficult to predict. Studies using supratherapeutic doses of testosterone and nandrolone have failed to produce any negative changes, suggesting that moderate AAS abuse may not be associated with impaired insulin sensitivity. At the same time, research indicates that heavy steroid abuse could lead to insulin resistance. Further studies are needed to assess the impact of steroid abuse on metabolic health.