Estriol is often described as the "weak" estrogen. But weak and gentle are not the same thing — and estriol really deserves a better nickname. What it lacks in sheer force, it makes up for in a unique molecular structure that researchers keep coming back to.

In fact, estriol has some qualities of its own that estradiol and estrone simply don't share. Here's what the research community has been paying attention to:

• Estriol has been the subject of ongoing research exploring its unique structural properties among the estrogens.
• Researchers interested in brain and neurological well-being have included estriol in their work, given its distinct receptor-binding profile.
• Studies have looked at estriol in relation to skin health, with a focus on how it may be involved in supporting skin membrane function.
• Research has associated estriol with supporting comfortable, well-moisturized intimate skin — without affecting the endometrium — a distinction that sets it apart from other estrogens.
• Transdermal administration has been noted in research as a commonly studied delivery method for estrogens during the menopause years.
• Estriol is one of the most widely discussed options in research on supporting vaginal comfort and moisture during menopause.

Estriol might be the gentlest of the three, but as the old saying goes, "Dripping water hollows out stone — not through force, but through persistence."

https://www.sciencedirect.com/topics/medicine-and-dentistry/estriol