29/10/2025
☕ Estrogen, MCAS & Coffee in your Follicular Phase
During this phase we see our bodies follicle-stimulating hormone (FSH) stimulating the ovarian follicles to mature and produce estrogen. As estrogen rises: the uterine lining thickens, fertile cervical mucus increases, energy and mood often improve… what has that got to do with coffee??
•• Well we know that…
Estrogen and histamine share the same receptor (H1). When estrogen rises, mast cells release histamine. Histamine then signals the ovaries to make more estrogen… creating a cycle of estrogen → histamine → estrogen → histamine.
Not fun for estrogen dominant ladies… so can my coffee help or hinder me? I have been thinking about why and when I crave coffee… and interestingly the follicular phase might be a time to grab that coffee!
Here’s where coffee might help:
Research published in the American Journal of Clinical Nutrition (NIH) found that caffeine can influence estrogen levels differently depending on race and the drink type:
• White women → coffee was linked to lower estrogen
• Asian women → coffee was linked to higher estrogen
• African American women → results were unclear
• Green tea & soda → raised estrogen in all groups
Why the difference?
Caffeine and estrogen share the same metabolic pathway — the CYP1A2 enzyme. Variations in this enzyme affect how you break down both caffeine and estrogen, which may explain why responses differ by race and individual genetics.
If you experience estrogen dominance, enjoying a cup of coffee in your follicular phase may be the prefect time!