Men who use anabolic steroids to bulk up and enhance performance face a markedly higher risk of long-term erectile dysfunction, new Danish research shows. Over a 15-year period, steroid users were three times as likely to require prescription medicines for impotence compared with non-users. The results are published in The Journal of Sexual Medicine.
Anabolic-androgenic steroids are synthetic variations of testosterone. While doctors may prescribe them for conditions such as delayed puberty or muscle-wasting diseases, outside medical settings athletes and bodybuilders often use them to increase muscle mass, reduce fat, and improve physical performance.
Current estimates suggest that around six percent of men worldwide will use anabolic steroids at some point in their lives.
The study explains that the human body relies on a delicate hypothalamic-pituitary-gonadal axis to regulate hormone production, operating on a negative feedback loop. When the brain detects an excess of testosterone, it curbs the body’s natural production.
When large amounts of artificial testosterone are introduced, the brain signals the body to slow production, which over time can cause the testicles to shrink and natural hormone production to crash. This disruption can lead to hypogonadism, a condition characterised by low testosterone and related symptoms such as fatigue and reduced muscle mass, with sexual health issues among the most common concerns.
Magnus Middelboe, a clinical pharmacologist at Copenhagen University Hospital-Bispebjerg and Frederiksberg, led the research team investigating the long-term risk of erectile dysfunction among men who use or have used anabolic steroids.
The researchers designed a longitudinal cohort study, following a defined group of people over time to observe health outcomes. They used Denmark’s national health and law enforcement records to identify steroid users and to track medical treatments and prescriptions from 2001 to 2018.
Steroid users were identified through Anti-Doping Denmark, an organisation that tests for performance-enhancing drugs in public fitness centres. The study included men sanctioned under the anti-doping programme, including those who tested positive and those suspected of using steroids without submitting a test.
For comparison, the researchers randomly selected men from the general Danish population and matched each steroid user with a contemporary peer of the same age and the same sanction date to create a fair baseline.
The average age at the start of the observation period was 27. Participants were followed until the end of 2022, or until death or emigration, with an average follow-up of about ten years.
To identify erectile dysfunction, the researchers turned to the Danish National Prescription Register, tracking new prescriptions for erectile dysfunction medications such as sildenafil and tadalafil. They also recorded the total number of prescriptions and the cumulative dose over the follow-up period.
Statistical models accounted for differences in socioeconomic status, adjusting for educational attainment and occupation at the start of the study.
The findings show a strong association between steroid use and the need for erectile dysfunction treatment. The 15-year risk of redeeming a prescription for erectile dysfunction medication was 24 percent among steroid users, compared with eight percent in the control group.
Raw data indicated that steroid users were 3.6 times more likely to seek their first treatment for erectile dysfunction than non-users. After adjusting for age, education, and employment, the estimate remained high at 3.2 times.
Among those who sought medical help for erectile dysfunction, steroid users filled more prescriptions than controls—median six versus three. They also reported a higher median cumulative dose, with interquartile ranges of 16 to 300 and 12 to 136 respectively, indicating greater treatment intensity among steroid users.
As the study is observational, it cannot definitively prove that steroids cause erectile dysfunction. The researchers relied on prescription records as an indirect proxy for the condition, which introduces potential misclassification, as some medications can treat other issues such as lower urinary tract symptoms or Raynaud’s disease. Additionally, medications obtained outside registered pharmacies were not captured, and erectile dysfunction is often underdiagnosed because many men are reluctant to discuss sexual health with clinicians.
The study recognises further limitations, including the possibility that sanctions by Anti-Doping Denmark may have led some men to stop using steroids, leaving them classified as users in the data. There was no detailed information on the duration or precise dosages of steroid use prior to sanction.
Medical professionals acknowledge that prolonged hypogonadism and testosterone suppression are likely important factors, though other biological and environmental influences—such as cardiovascular disease, psychological stress, and use of other recreational drugs—could also contribute to the higher rates of erectile dysfunction observed. Lifestyle factors such as smoking and alcohol use were not measured in the study.
The researchers, led by Magnus Middelboe and colleagues Ida M. Heervaldt, Josefine Windfeld-Mathiasen, Kim Peder Dalhoff, Jon Trærup Andersen, and Henrik Horwitz, published their findings under the title Anabolic-androgenic steroid use and erectile dysfunction.
