Research suggests taking HRT DOESN’T give you protection against dementia despite claims treatment has ‘protective effects’ on the brain

It’a an eye-catching claim often trumpeted by celebrity doctors and health campaigners on social media. Taking hormone replacement therapy (HRT) to relieve symptoms of the menopause also has ‘protective effects’ on the brain, they say – and can reduce women’s risk of developing dementia.

TV presenter Davina McCall, whose father had Alzheimer’s, said in 2021, the year before he died, that she hoped HRT would provide her with ‘a bit more protection’ against the disease.

But the Lancet Commission, which analysed the best research on this subject for the first time, has poured cold water on those claims.

It even found evidence that there may be a slightly increased risk of dementia for some taking these mid-life hormones, which usually involves a combination of oestrogen and progesterone.

Dementia is more common in women than men – almost two thirds of those with Alzheimer’s, for example, are women.

The hormone changes of the menopause have been suggested as a possible reason for this, which is why HRT – which replenishes levels of oestrogen and progesterone as they decline in midlife – has been suggested as protective.

But studies assessed by the commission included one that found an increased risk of Alzheimer’s in women who took both oestrogen and progesterone for between five and nine years. The risk increased with more years of use – from a 21 per cent increase for HRT use of less than a year, to 74 per cent for more than 12 years. 

One major analysis of 23 clinical trials reported that any form of HRT had a small but statistically significant negative effect on thinking and memory.

Crucially, it found no positive effect, whether women used HRT for up to six months or for years. There was even more of a negative impact if a woman started taking HRT after the age of 60, it found.

Another analysis of hundreds of trials found ‘high-quality evidence’ that post-menopausal women should not take oestrogen to prevent dementia because it could actually increase their risk.

Menopausal mature woman suffering with insomnia in bed at home

Campaigners often dismiss these kinds of studies because some involve older forms of HRT no longer routinely used, including oestrogen tablets, and say newer forms with gels and creams are safer.

But while the exact relationship between HRT and dementia is still unclear, the report’s lead author, Professor Gill Livingston at University College London, says: ‘We could not find any evidence that HRT reduces the risk of dementia.

‘While it’s true the evidence that HRT can be harmful comes from old-style formulations, we still don’t have evidence the new versions are protective.

‘I understand lots of people feel immensely different on HRT but I’m afraid we just don’t have the evidence that it improves cognition.’