Over a 2-year period, a third of the men randomized to a weight loss program demonstrated resolution of erectile dysfunction.10 A Mediterranean diet and nutritional counseling reported increased erectile quality.18 Little evidence supports that increased physical activity alone improves erectile quality; however, the strong association between physical activity and lower BMI is well described, and therefore recommended for men with erectile dysfunction and without a contraindication to physical activity.
Impotence, also known as ED – erectile dysfunction, is a quite common health issue that several men have to face. According to the Massachusetts Male Aging Research, it could be estimated that 1/2 of men in the world may experience erectile dysfunction at some point. At age 40, about 40% of men have to face this sexual health issue, and it would be even more common in people at older ages.
Erectile dysfunction (ED) affects 50% of men older than 40 years,  exerting substantial effects on quality of life.  This common problem is complex and involves multiple pathways. Penile erections are produced by an integration of physiologic processes involving the central nervous, peripheral nervous, hormonal, and vascular systems. Any abnormality in these systems, whether from medication or disease, has a significant impact on the ability to develop and sustain an erection, ejaculate, and experience orgasm.
Lifestyle choices that impair blood circulation can contribute to ED. Smoking, excessive drinking, and drug abuse may damage the blood vessels and reduce blood flow to the penis. Smoking makes men with atherosclerosis particularly vulnerable to ED. Being overweight and getting too little exercise also contribute to ED. Studies indicate that men who exercise regularly have a lower risk of ED.
As with most other organ system in the human body, changes and loss of function is normal consequence of the ageing process. This is also true of the endocrine system, specifically the levels of testosterone production from the Leydig cells of the testicle. Accompanying the decrease in testosterone is a decrease in erections which also has a component in decrease in the blood supply to the penis making erection not as frequent and not as rigid compared with a young man’s erectile function. Although these changes are in itself not life threatening, they can impact a man’s relationship with his partner, and also ED may be a harbinger of other undiagnosed conditions such as coronary artery disease (CAD), hypercholesterolaemia or diabetes mellitus.6
Commercials for drugs to improve “low T,” or testosterone, the male hormone, are now vying for airtime, but they address desire, not performance. "Male hormone is not an approved treatment for erectile dysfunction," notes Bennett. "It may be used to increase desire in men who have low testosterone, but it doesn’t improve blood flow to an erection." A doctor can do a blood test to check you for low testosterone, but it is a rare cause of ED. Hormone therapy with injections, patches, or gels applied to the skin may improve mood and sex drive, but it likely won’t fix any mechanical issues. Also, testosterone drugs should not be used by men with prostate cancer. Side effects include acne, breast enlargement, prostate enlargement, and fluid retention.
These are not currently approved by the FDA for ED management, but they may be offered through research studies (clinical trials). Patients who are interested should discuss the risks and benefits (informed consent) of each, as well as costs before starting any clinical trials. Most therapies not approved by the FDA are not covered by government or private insurance benefits.
Alprostadil may be delivered via the urethra in the form of a pellet (MUSE) (107). This form of therapy has been trialed in SCI men with intermediate success (108). Bodner trialed MUSE dose escalation in SCI men and found 1,000 μg to be the most effective dose. Several men had hypotension when a constriction ring was not used in conjunction with the MUSE therapy.
In a prospective, multicenter, single-armed study of ED patients who exhibited a suboptimal response to PDE5 inhibitors, the investigators found that percutaneous implantation of zotarolimus-eluting stents in focal atherosclerotic lesions was both safe and feasible and was associated with clinically meaningful improvement on subjective and objective measures of erectile function. 
Diabetes is an example of an endocrine disease that can cause a person to experience impotence. Diabetes affects the body’s ability to utilize the hormone insulin. One of the side effects associated with chronic diabetes is nerve damage. This affects penis sensations. Other complications associated with diabetes are impaired blood flow and hormone levels. Both of these factors can contribute to impotence.
Injections: Injections are a reliable way to restore testosterone levels, but this therapy requires periodic injections (usually every two weeks) to sustain an effective level. It also causes high hormone levels right after the injection and low hormone levels just before the next shot. This is thought to be slightly more risky than other methods that maintain a moderate hormone level throughout the treatment period.
Parasympathetic pathways originate from the intermediolateral cell columns of the 2nd, 3rd and 4th sacral spinal cord segments. Preganglionic fibers pass through the pelvic plexus where they coalesce with sympathetic fibers from the superior hypogastric plexus. The cavernous nerves that innervate the penis arise from the portion of the pelvic plexus. The pelvic plexus also contains nerves that innervate the rectum, bladder and urinary sphincter and the nerve projections can be damaged during radical excision of the bladder, prostate and rectum, leading to iatrogenic ED (4).
The sympathetic pathway originates from the 11th thoracic to the 2nd lumbar spinal segments and goes via the white rami to enter the sympathetic chain ganglia. Subsequently nerves travel through the lumbar splanchnic to inferior mesenteric and superior hypogastric nerves to the pelvic plexus. The T10 through T12 segments are most often the origin of sympathetic fibers, and the sympathetic chain ganglia that innervate the penis are located in the sacral and caudal ganglia (3).
One study examined the role of testosterone supplementation in hypogonadal men with ED. These men were considered nonresponders to sildenafil, and their erections were monitored by assessing nocturnal penile tumescence (NPT). After these men were given testosterone transdermally for 6 months, the number of NPTs increased, as did the maximum rigidity with sildenafil.  This study suggests that a certain level of testosterone may be necessary for PDE5 inhibitors to function properly.
Medication — When a medication is the cause of the dysfunction, a change in the medication may help. Men and women with hormone deficiencies may benefit from hormone shots, pills, or creams. For men, drugs, including sildenafil (Viagra®), tadalafil (Cialis®), vardenafil (Levitra®, Staxyn®), and avanafil (Stendra®) may help improve sexual function by increasing blood flow to the penis.
Guilt is a painful and gut-wrenching emotion. It is identified in this article as one of the possible causes of psychological impotence. If your guilt is strong enough, it interrupts the signals between your brain and body, stopping you from getting an erection. It’s almost as if the unconscious mind punishes you by denying you pleasure in response to the guilt that you feel.
ICI Alprostadil may be used as a mixture with two other drugs to treat ED. This combination therapy called "bimix or trimix" is stronger than alprostadil alone and has become standard treatment for ED. Only the Alprostadil ingredient is FDA approved for ED. The amount of each drug used can be changed based on the severity of your ED, by an experienced health professional. You will be trained by your health professional on how to inject, how much to inject and how to safely raise the drug's dosage if necessary.