What did the Women's Health Initiative (WHI) initially find about MHT?

The WHI initially reported that women on MHT had higher risks of heart disease, stroke, breast cancer, and dementia.

Does starting MHT later in life increase dementia risk?

Yes, studies suggest that starting MHT at age 65 or older, or more than five years after menopause, may increase the risk of dementia.

Are all types of MHT the same for brain health?

No, different types of MHT and delivery methods have varying effects on brain health; some may support cognition while others do not.

Home / Health / MHT Myths Busted: What You Need to Know for Brain Aging

MHT Myths Busted: What You Need to Know for Brain Aging

12 Dec, 2025

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Summary

Starting MHT around menopause may support brain health.
Later MHT starts may increase dementia risk and tau buildup.
Different MHT types and delivery methods impact brain health.

MHT Myths Busted: What You Need to Know for Brain Aging

Early findings from the Women's Health Initiative in the early 2000s raised concerns about menopause hormone therapy (MHT), suggesting increased risks for heart disease, stroke, and cancer. However, subsequent re-analysis of this data has refined understanding, indicating that for many women, MHT can be safely prescribed around menopause to manage symptoms, with benefits often outweighing risks.

The critical window hypothesis highlights that initiating MHT during the menopausal transition may support brain health, whereas starting it years later could be linked to cognitive decline. Recent studies suggest varied outcomes, with some women experiencing cognitive benefits, while others see no negative impact. However, later MHT initiation has been associated with increased tau protein buildup, a marker for Alzheimer's disease.

Furthermore, the type and delivery method of MHT significantly influence its effects. Newer forms like 17-beta estradiol are often preferred over older combinations, and transdermal methods (patches, gels) may carry fewer risks than oral pills by bypassing the liver. MHT is not a dementia prevention strategy but can support well-being and potentially brain health for those who struggle with menopause symptoms.