How can I stop my penis from shrinking?

See answer. Though there is some degree of penis shrinking with age and/or lack of use, most shrinking of the penis is perceived rather than real and related to gaining weight and/or shifting of the fat to the lower abdomen and genital area above the base of the penis causing it to be buried and look smaller. Rx: losing weight, eating healthy and staying fit and sexually active. There are no shortcuts or med.