My mother is in her 60's and on Paleo. Many years ago she was on hormone replacement therapy for hot flushes but stopped before the studies showed it was a problem. She gave up flaxseeds during initial Paleo but then her hot flashes came back. She returned to using them 1 tsp a day on berries and/or banana and the hot flushes went away.
What's the research on this?
I'm seeing that the links Dave gave show conflicting results. I'm thinking that the savior/problem is the lignans (phyto-estrogens) in the flaxseed. One article noted that those lignans are probably interfering with natural estrogens: I'm thinking there's a combination of interfering with some actions and enhancing others, and that "mileage may vary" in different people.
If it helps, it helps. (Might help if she grinds or cooks the seed, though--preferably both!)
There are phyto-estrogens in flaxseeds, much like soy. I don't know of any studies to cite, but my nutrition instructor told us that she worked once at a gym specifically for women who were on soy protein and flax shakes and having a lot of issues around menopause and stalled weight loss. She switched them to a shake based on a high quality whey protein, most of the women's symptoms ceased, and weight came off easily.
Edit:I also wonder if flax helps the liver simply by keeping digestion moving along, thereby allowing the liver to process excess hormones with no toxic overload.
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