Low Testosterone Levels Linked to Cognitive Decline in Older Women (and Why It May Also Matter for Younger Women)
A recent study from the Korean Frailty and Aging Cohort offers new insight into how testosterone—a hormone most people think of as “male”—appears to play an essential role in women’s brain health.
Study Findings
Researchers studied 2,710 older Korean adults (ages 70–84) to understand how free testosterone (FT) levels relate to cognitive function.
Their findings were striking:
- In women, lower FT levels were significantly linked to poorer performance across multiple brain functions:
- Global cognition (MMSE)
- Memory (Word List Memory)
- Processing speed (Trail Making Test)
- Executive function (Frontal Assessment Battery)
- Women in the lowest quartile of FT had the highest risk of cognitive impairment.
- In men, there was no clear link between testosterone levels and cognition.
These findings mean that low testosterone appears to have a sex-specific effect, with women being more sensitive to its loss.
Why This Matters for Women
Most people know that 17-beta estradiol levels in the blood drop sharply during the midlife transition to age-related Physiologic Primary Ovarian Insufficiency (AKA Menopause). Still, few realize the ovaries also produce about half of a woman’s daily testosterone.
At the NIH Intramural Research Program, a study in young women with Primary Ovarian Insufficiency (POI) showed that they have significantly lower testosterone levels than age-matched women with normal ovarian function. This finding means Primary Ovarian Insufficiency—whether it happens in youth or naturally at midlife—affects both estradiol and testosterone production.
The findings suggest, but do not prove, that hormones may help support key brain regions, such as the frontal cortex and hippocampus, which are vital for memory, focus, and emotional regulation.
The Big Picture
Researchers suggest that there may be a minimum threshold of testosterone necessary to help preserve cognitive performance in women.
Low testosterone—from natural aging or Primary Ovarian Insufficiency in adolescents and young women—may possibly leave the brain more vulnerable to early functional decline.
These findings may also help explain why women experience higher rates of Alzheimer’s disease and dementia compared to men after midlife.
But here’s the challenge. We don’t yet have extensive, long-term studies proving that replacing testosterone at physiologic levels (normal levels for women) prevents cognitive decline.
That’s why more research—specifically designed for women—is urgently needed.
Important Caution
This study was cross-sectional, meaning it can only show associations, not cause-and-effect. It takes prospective controlled studies to demonstrate cause and effect. Still, the study sends an important message: Hormones seem to matter for brain health — and women’s hormones deserve dedicated, sex-specific research.
Takeaway for Women
If you have Primary Ovarian Insufficiency or are navigating midlife hormonal changes, talk with your clinician about your complete hormone profile – not just estradiol.
Both estradiol and testosterone may play vital roles in maintaining:
- Brain function
- Bone strength
- Muscle mass
- Mood and motivation
These findings don’t mean everyone should take hormones — but the findings do mean we should be talking about them more openly and studying them more thoroughly.
Read the abstract at NIH:
(Note: Full article is behind a paywall.)
We share this research to inform and empower, not to provide medical advice. Always discuss your individual situation with a qualified healthcare provider.
