For men in general, the cause of impotence is nowadays thought to have an underlying physical basis in about 75% of cases. For men over 50, that figure jumps to 90%. Also for men over 50, almost one half of erectile dysfunction is due to arteriosclerosis of the penile arteries. The buildup of plaque in the penile arteries involves the similar kinds of plaque that clog the walls of other arteries, including the coronary arteries.

J. E. Morley has indicated, in an article in Postgraduate Medicine, that such erectile dysfunction may serve as an indicator for future heart attack or stroke.

We have seen that HGH has been instrumental in reducing cholesterol levels in the blood, particularly LDL, the component that contributes most to the buildup of plaque on artery walls. Although research has yet to confirm it definitively, with the reduction of LDL in the blood, one would tend to conclude that it would reduce the plaque buildup in the penile arteries. There is a theory relating to the finite number of sexual encounters in one lifetime allowed by oxidative stress.

Further, some of the main risk factors for heart disease, such as smoking, high cholesterol (especially LDL) levels, high triglyceride levels, also comprise some of the same risk factors for impotence. If we revisit the study done at Palm Springs, we will recall that a figure of 75% was reported for improvement in sexual potency and frequency by over 200 patients in that study. Since HGH has shown itself, in this study and others, to confer remarkable improvements in patients' sex lives, and since HGH has also shown itself to be efficacious in ameliorating conditions often attendant with poor sex lives, such as high cholesterol and high triglycerides, could it be that HGH is working on the physiological root cause of both? Or working on something that is at least a partial root cause of both?