Since sexual arousal is a complex process involving hormones, emotions, nerves, muscles, blood vessels and the brain, a malfunction in any of these can lead to erectile dysfunction. Stress, exhaustion and psychological issues can also contribute, and anxiety over maintaining an erection can actually make it harder to attain. In short, any condition that inhibits blood flow to the penis can lead to erectile dysfunction.
According to the AAFP and the Mayo Clinic, erectile dysfunction can be caused by:
Heart disease or clogged blood vessels
High blood pressure
Diabetes
Obesity
Metabolic syndrome, a grouping of conditions that include high blood pressure, cholesterol and insulin levels and excess fat around the waist
Multiple sclerosis
Parkinson’s disease
Low testosterone
Peyronie’s disease, which is scar tissue inside the penis
Certain prescription drugs, such as antidepressants and high blood pressure medication
Smoking
Alcoholism or drug addiction
Prostate treatments
Brain or spinal cord injuries
Stroke
Radiation therapy to the testicles
Certain types of surgery on the prostate or bladder
The vast majority of erectile dysfunction cases are caused by disease, according to the National Institutes of Health (NIH), while drug side effects account for 25 percent.
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