Research suggests taking HRT does NOT protect you against dementia, despite claims the treatment has a ‘protective effect’ on the brain

It’s a bold claim often trumpeted by celebrity doctors and health campaigners on social media. Hormone replacement therapy (HRT) to relieve menopausal symptoms also has “protective effects” on the brain, they say – and can reduce women’s risk of dementia.

TV presenter Davina McCall, whose father had Alzheimer’s, said in 2021, the year before he died, that she hoped hormone therapy would give her “a little more protection” against the disease.

But the Lancet Commission, which for the first time analyzed the best research on the subject, has dismissed these claims.

There was even some evidence that there is a slightly increased risk of dementia for people who take these hormones in middle age, usually a combination of estrogen and progesterone.

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

Stock image: Hormone replacement therapy, also known as HRT. The hormonal changes of menopause have been suggested as a possible reason for this, and so HRT – which replenishes levels of estrogen and progesterone as they decline in midlife – has been suggested as protective

The hormonal changes of menopause have been suggested as a possible reason for this, and HRT – which supplements estrogen and progesterone levels when they decline in middle age – has been suggested to have a protective effect.

But studies reviewed by the committee included one that found an increased risk of Alzheimer’s in women who took both estrogen and progesterone for five to nine years. The risk increased with more years of use — from a 21 percent increase for HRT use of less than a year, to 74 percent for more than 12 years.

A major analysis of 23 clinical trials found that each form of HRT had a small but statistically significant negative effect on thinking and memory.

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

Another analysis of hundreds of studies found that there is “high-quality evidence” that postmenopausal women should not take estrogen to prevent dementia, as it may actually increase the risk of dementia.

Adult menopausal woman suffering from insomnia in bed at home

Campaigners often ignore these studies because some of them involve older forms of HRT that are no longer routinely used, such as oestrogen tablets. They argue that the newer forms using gels and creams are safer.

Although the exact link between HRT and dementia remains unclear, the report’s lead author, Professor Gill Livingston from University College London, said: ‘We couldn’t find any evidence that HRT reduces the risk of dementia.

‘While it is true that the old formulations show that HRT can be harmful, we still have no evidence that the new versions provide protection.

“I understand that many people feel dramatically different on hormone replacement therapy, but I’m afraid we simply don’t have any evidence that it improves cognition.”