Hundreds of thousands of Scottish men have a low sex drive that could be helped with the same testosterone boost used by Robbie Williams, a world health conference in Glasgow will hear tomorrow.
Research has found that 20 per cent of Scotland's one million men over the age of 45 could be living with Testosterone Deficiency Syndrome or Andropause.
Despite being available on the NHS, only 1 per cent of the Scots men who could benefit from Testosterone Replacement Therapy - as used by the Take That star - are being treated.
The health experts who carried out the research, Professor Tom Trinick, Dr Mark Feneley and Dr Malcolm Carruthers, will present their findings at the 20th World Congress for Sexual Health in Glasgow.
Tomorrow, Dr Carruthers, President of the Society for the Study of Androgen Deficiency (The Andropause Society) will tell the bi-annual congress at the SECC that symptoms can include decreased sex drive, erection problems, loss of energy, depression, weight gain, memory loss, irritability and night sweats.
"It's astonishing that the most common hormonal disturbance in men, which can wreck their lives, loves and health, is the least commonly treated," he said.
"Whilst there is increasing recognition among doctors that Testosterone Deficiency Syndrome is a common and important condition, there is still some resistance.
"The condition (TDS) can be difficult to diagnose other than from the very characteristic symptoms, because the overall level of testosterone in the blood is often within so-called normal limits.
• Case study: 'I generally feel so much more positive about life'
"In my experience this makes doctors reluctant to accept the idea that the patient may have the condition and is one of the main reasons why it is so rarely recognised and treated."
The peak age for TDS is 50 but it can present earlier for a variety of reasons.
Earlier this month, Williams told Esquire magazine he injects himself with hormones that boost his sex drive after he was told he had "the testosterone of a 100-year-old man".
Dr Carruthers said: "Even though he is relatively young at 37, to be testosterone deficient, living life in the fast track, with a reported history of alcohol and drug excess is likely to be a factor.
"Contrary to certain opinions in the media recently, I don't believe Testosterone Replacement Therapy (TRT) poses a threat to Robbie's health as he will need TRT to maintain the high level of physical and mental activity needed for his performance."
However, he said that if Williams wants to start a family, he should think about taking a rest from his injections and replace them with the milder and more commonly used TRT gels.
"In high doses, testosterone can be used as a fully reversible male contraceptive so Robbie might need to take a few months off the injections to restore his fertility and fulfil his ambitions to have a family.
"The other forms of TRT such as the gels, raise testosterone levels while maintaining fertility."Dr Carruthers rejects the notion that TRT has serious adverse side effects such as high blood pressure and can damage the heart. Unfortunately, views about the dangers of TRT are about 20 years out of date," he said.
"Rather than being dangerous, carefully regulated and monitored TRT is remarkably safe, as my own experience in treating more than 2,000 men in the last 20 years in my Centres for Men's Health has shown.
"This is backed by studies that highlight the benefits of TRT for the heart and prostate.
"It reduces obesity, can prevent complications of diabetes, can lower cholesterol and is being used to treat heart attacks and strokes in diabetics.
"It makes men calmer, more loving as well as happier and sexier. It restores the life in the man, which had gone down the pan."