Expose' : How your man can retain his virility PART 1

Male virility is a complex business, with implications not just for men's love lives, but their health, too, as a new book reveals.

The author, Dr Ronald Virag, is a French cardiovascular surgeon and leading authority on male sexual health and erectile dysfunction (he pioneered the use of injections to treat the problem). Here Dr Virag reveals some surprising facts about men's sexual function - and what to do when it goes wrong . . .

YES, YOU CAN HOLD BACK THE RAVAGES OF TIME

Just as men develop grey hair and creaky joints as they hit middle age, from the age of 40, their blood vessels start to age, affecting their virility. The blood vessels become furred with fatty deposits, impeding blood flow to the penis.

This lack of blood also means that some of the tissue around the vessels becomes deprived of oxygen - another trigger for erectile dysfunction. Before the age of 40, less than 10 per cent of men have concerns about their erections - after that, more than 50 per cent complain of problems, and it is a worry for the vast majority of the over 70s.

Another problem is that from the 40s onwards, testosterone levels drop because the testicles aren't able to produce as much of it.

Animal studies have shown that lower levels of testosterone affect penile tissue. There are testosterone receptors, which bind to the hormone to make it effective, inside the penis so they won't be activated if there isn't enough of the hormone, making it difficult for the penis to become rigid.This phase has been dubbed the 'andropause' as the time it starts matches the time of the female menopause (although while the menopause affects a woman's fertility, this is not as dramatic in men). 

However, regular sexual activity can help to maintain erections - and may also even extend life expectancy. Studies show that men over 50 have a longer life expectancy if they have at least two orgasms a month, compared with those who have none, while heart attack patients survive longer if they have frequent sexual activity.

Scientists are unsure of the reasons behind this, but say that the rush of feel-good compounds may boost health by lowering blood pressure and boosting heart health. As we will see, one of the key lessons about male virility is that an active sex life creates a virtuous cycle - it makes erectile dsyfunction less likely, protects a man's prostate and even stops the penis shrinking with age. In other words: use it or lose it!

VIRILITY REVEALS HOW HEALTHY YOU ARE

Struggling to achieve and maintain an erection can indicate more than a localised problem - it can be a sign of other underlying health conditions.

Depression undermines sexual desire, while antidepressants can often hinder sexual function because they reduce desire in the brain. (Although some medications, such as tricyclic drugs often used as treatment for mental health problems, can spontaneously cause erections, possibly because they spark metabolic changes.)

Erectile dysfunction can also be an early sign of multiple sclerosis - which damages nerves. Around 5 to 10 per cent of male MS patients are affected in this way. Erection problems can also be the first sign of diabetes, because a high blood sugar level prevents the automatic production of nitric oxide, a compound that helps widen blood vessels.

 Erection difficulties can also suggest furred-up arteries (risk factors include high cholesterol, smoking, alcohol, diabetes, high blood pressure and obesity) - even a small blockage in the penile arteries will lead to a poor-quality erection because the vessels are so narrow. Studies suggest that in a group of men with penile artery disease, 50 to 75 per cent of them will also have the early stages of blocked arteries around the heart. So as well as being a symptom of heart disease, erectile dysfunction can be a vital early warning sign of it. Therefore, the risk factors need to be addressed. A supplement called arginine may also help - it works mainly by increasing the production of nitric oxide.

WHY SLEEP IS SO IMPORTANT

Disrupted sleep cycles are a cause of reduced or absent automatic nocturnal erections. While we sleep the body undertakes maintenance and repair to all our cells and tissues, including the genitalia.

Throughout the night men experience a number of erections, which are thought to be crucial to the health of penile tissue. These occur in the REM (rapid eye movement) phases of sleep, also known as dreaming sleep, at the end of the 90-minute adult sleep cycle. We have four or five of these cycles in a healthy night's sleep, and often wake up during the REM phase, which is why men experience morning erections.

Erections occur when blood flows into chambers in the penis - most of the time, the sympathetic nervous system releases low levels of adrenaline, which reduces the flow of blood by contracting muscles in the penis.However, during REM sleep, a different branch of the nervous system takes over, taking the brakes off, and widening the blood vessels.

The increased blood flow means a greater supply of oxygen and nutrients - without this regular flow, the tissue can become deficient in oxygen, and studies suggest this can even lead to damage in the layer of tissue, affecting the ability of the penis to become rigid. Indeed, scientists have found that men whose automatic nocturnal erections reduce or disappear have more difficulty sustaining erections when awake.These kinds of problems can be triggered by a disrupted sleep cycle (caused by taking sleeping pills or working night shifts). Men who no longer experience automatic morning erections may want to see their GP, especially if it's accompanied by a difficulty maintaining or gaining an erection when aroused.

To be continued