Male testosterone levels have plummeted by 54% between 1972 and 2019, equivalent to a decline of more than 1% annually, according to data from 118,593 individuals presented at the European Society of Human Reproduction and Embryology in London on July 7. Researchers described the trend as 'strong' and 'staggering,' prompting urgent concerns for men's reproductive and overall health.
Health Risks and Expert Warnings
Dr. Jeff Foster, author of the testosterone handbook Optimal, told Metro: 'It's a staggering statistic that's concerning for several reasons. We need testosterone to stay healthy throughout our entire lives.' He highlighted that low testosterone is linked to increased risks of heart attack, diabetes, mental health problems, social and work difficulties, and mortality. 'If your testosterone is low, you simply have a greater risk of dying sooner,' Dr. Foster added. 'This is a really important statistic we cannot ignore.'
The findings have been dubbed a 'crisis' by researchers. Dr. Foster agreed, stating: 'Worst case, this could lead to a reduction in fertility, a reduction in lifespan, and healthspan for men with a reduced level of testosterone.' More subtle impacts include fatigue, reduced libido, and a poorer quality of life. 'Men may just feel like the quality of life is not as good as it was,' he said.
Contributing Factors: Obesity, Diabetes, and Environmental Toxins
Four suspected factors are driving the decline. Obesity and diabetes are major contributors: excess body fat converts testosterone into oestrogen. In 2024, 66% of UK adults over 16 were overweight or obese, including 70% of men, according to the NHS. Additionally, 6 million people in the UK have diabetes, 90% with type 2.
Global heating is another factor, with Earth's average temperature roughly 3.2°C above pre-industrial levels, per the Met Office. The third factor is endocrine-disrupting chemicals found in household items like non-stick cookware, personal care products, and canned foods. Dr. Foster noted: 'A lot of the blame has been put down to environmental contaminants, things like microplastics or endocrine disruptors, and there is no doubt these play a role in reducing male testosterone production.' However, he added, 'we don't know how much these environmental contaminants actually impact overall testosterone levels.'
Impact on Health and the NHS
Dr. Foster warned of 'catastrophic' consequences: 'A significant drop in testosterone is going to lead to a much poorer quality of life. You will be less happy. You will be less healthy. Your physical, your mental, and your sexual health will be worse, and your overall risk of multiple medical problems will go up.' This will place increasing strain on the already stretched NHS.
How to Boost Testosterone Levels
Despite environmental concerns, Dr. Foster emphasized lifestyle factors within men's control. He advises: getting six to seven hours of unbroken sleep nightly; reducing chronic stress (nine in 10 Brits have experienced high stress in the last year, per Mental Health UK); exercising at least three to four times per week at an intensity that raises heart rate or causes muscle fatigue; and maintaining a healthy mixed diet (only 32.5% of adults eat five portions of fruit and vegetables daily).
'To improve your testosterone levels as a man, you need to optimise the things you do in your lifestyle to make sure your testicles and brain are given the best chance to produce the most testosterone they can,' Dr. Foster explained. If symptoms persist despite lifestyle changes, he urges men to get their testosterone levels checked, especially if over 30. 'All the lifestyle changes in the world will not undo a medically caused testosterone deficiency,' he said. 'If you have true testosterone deficiency, then the only way to treat that is with male hormone replacement, TRT.'
