A groundbreaking 2024 study has shifted the narrative away from past medical thinking that women should discontinue hormone therapy by age 65. By analyzing real-world data for 14 years from over 10 million Medicare-enrolled women, all aged at least 65 at the start of the 14-year trial, researchers gained an unprecedented look at how continuing or initiating HT later in life can benefit long-term health.

Unlike smaller clinical trials, this large-scale analysis provides a comprehensive view of the influence of hormones on the risks of over 40 serious illnesses, cancers, and mortality. The findings are optimistic: for many women, hormone therapy can actually reduce the risks of numerous serious illness, supporting a longer and healthier life.

This study was published in the journal Menopause, the official, peer-reviewed journal of the American Menopause Society, aimed at for physicians and scientists, and focused on research and clinical guidelines for midlife women’s health, gynecology, menopause management, and hormone therapy.

Protective Benefits: What the Science Says  

When comparing women over 65 who took hormones to those who did not, the study found significant health advantages:

1. Heart Health

The research found a strong protective effect against cardiovascular issues for women using hormones over the 13 study years, compared to non-users:

• Heart Attack (Acute Myocardial Infarction): Risk reduced by 15% to 20% for hormone users
• Heart Failure: Risk reduced by approximately 11%.
• Atrial Fibrillation: Risk reduced by about 9%.

2. Brain Health

One of the most striking findings of the study was the impact on neurodegenerative diseases, which had been a major point of concern in previous decades:

• Alzheimer’s Disease: Risk reduced by 14% to 15% for hormone users
• General Dementia: Risk reduced by 10% to 11%.

3. Bone Strength

The study reaffirmed HT’s role in bone preservation. HT remains one of the most effective ways to prevent osteoporosis and painful hip fractures

• Hip Fractures: Risk reduced by 15% for hormone users.
• Osteoporosis: The incidence was lower by as much as 5 to 8-fold in women using hormones versus taking none.

4. Redefining Cancer Risk

Cancer Risk: By the Numbers

For years, the medical conversation around hormone replacement was overly dominated by a singular focus on cancer risk. In reality, since at least 2012 science has shown reduced cancer risks for women taking estrogen. The latest results confirm surprisingly strong benefits: For many women, hormone therapy doesn’t just manage symptoms—it appears to be protective. When we look at the most common malignancies, the 2024 data shows that biologically-identical hormone replacement is associated with significant reductions in several major cancers.

The Critical Difference: Natural Hormones vs. Synthetic

While the historical stigma surrounding cancer has been largely overstated, the study highlights one vital distinction: The type of hormone matters.

• Natural Progesterone: Works in harmony with the body to provide the protective benefits seen in the table above.
• Synthetic ‘Progestins’ (e.g., MPA or Provera): These are manufactured fake chemicals that do not exist anywhere in nature or human or animal bodies, not true hormones. These synthetic ‘progestins’ were used widely from 1973 to 2002, instead of progesterone, probably because they were more profitable. Research since 2002 has confirmed that these synthetic ‘progestins’ are linked to higher risks of breast cancer and heart disease, and an 11% increased risk of death.
• Estrogens of various types: all appear to be protective against cancers.

For bioidentical, natural hormones, the data points toward significantly lower risks of death and a wide array of chronic illnesses. The so-called danger in older studies associated with ‘HRT’ was frequently due to synthetic chemical ‘progestins’ such as Provera.

5. Other Conditions

The incidence of blood clot, stroke, high blood pressure, high cholesterol, diabetes, migraines, rheumatoid or osteoarthritis, and many other conditions were lower by as much as 5 to 8-fold in women taking hormones versus taking none.

6. Longevity

The most significant takeaway from this study is that hormone therapy is linked to a longer life.  Estrogen use beyond age 65 years is linked with a major 19% reduction in mortality relative to no estrogen use. During the 14-year study period, there were 113,226 fewer deaths among women taking estrogen compared to those who took none. Progesterone taken alone was associated with a 22% reduced death risk, even better than estrogen.

Conclusion

This 2024 study marks a turning point in women’s healthcare, proving that the benefits of hormone therapy do not disappear at age 65. By choosing the right type of therapy—specifically focusing on bioidentical options—women can significantly lower their risk of the many common diseases and live a longer, stronger, more clear-minded life.

References