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Soy Phytoestrogens for Menopause Hot Flashes

August 26, 2019

“Soy Phytoestrogens for Menopause Hot Flashes” When women hit menopause and
their ovaries shut down, the estrogen level in their body drops 95%. This is good news for the endometrium,
the lining of the uterus. Otherwise the constant estrogen signaling could eventually result in endometrial cancer. In fact, maybe that’s why menopause evolved: to protect the uterus from cancer. Lower estrogen levels are also good for lowering breast cancer risk. In postmenopausal women, relatively
high blood levels of estrogen are associated with a more than
double increased risk for breast cancer. Estrogen levels drop 95% at menopause, but not to zero, because other tissues can make estrogen, like our own fat cells. This probably explains the
increase in breast cancer risk in obese postmenopausal women. More fatty tissue means
more estrogen production. Now we learned that soy phytoestrogens can block the production of estrogen, such that drinking a glass
of soymilk with each meal can cut estrogen levels in half in premenopausal women. But levels in postmenopausal women are already down 95%, and because of that, many women suffer from hot flashes. Might lowering levels even further with soy make menopausal symptoms even worse? Estrogen treatment is very effective in reducing menopausal symptoms. Unfortunately, the downside is not only the uterine cancer, but blood clots, strokes, and cognitive impairment. Taking progesterone-type compounds with the estrogen helps prevent the uterine cancer, but increases the risk of heart attacks, more stroke risk, breast cancer, more clots, and dementia. So what’s a woman to do? Well, the 80% hot flashes figure is not universal. Maybe 80 to 85% in European and American women, but it may be as low as
just 15% in places like Japan. In fact, there’s not even a word
for it in the Japanese language, which supports how relatively rare it is. Maybe the phytoestrogens in soy are helping? The association between soy product intake and the occurrence of hot flashes was examined by following a thousand Japanese women before they started menopause, over time, to see who developed hot flashes and who didn’t. And those women who were eating like 4 ounces of tofu a day appeared to cut their risk in half, compared to women who only
ate an ounce or two a day, suggesting soy products are protective. But maybe soy intake is just a marker for a healthier diet over all? A study in China found that the consumption of whole plant foods in general seemed to be associated with decreased menopausal symptoms. So to see if soy was something special, you’d have to put it to the test. Studies like this, of soy
phytoestrogens in pill form, showed extraordinary results, a significant drop in hot flash presence, number, and severity—from 100% of women suffering at the beginning to only 31% suffering by the end of 3 months. The average number of hot flashes dropped from about 120 a month down to 12. But the problem with studies like these is that there’s no control group to control for the placebo effect. If you look at all the hormone trials, even the women who got the placebo sugar pills had up to a 60% reduction in
hot flashes over the years. That’s why any therapy purported
to reduce such symptoms must be assessed in blinded
trials against a placebo because of the large placebo effect, and also because menopausal
symptoms often decline on their own over time. So if you saw a study like this, where they gave women a soy protein powder and saw a nice drop in hot flashes over the next 12 weeks, you’d think it looks pretty effective, but that’s the placebo powder group. Here’s the group that got the soy, significantly better than placebo. But it’s important to recognize how powerful the placebo effect can be. Over the past 20 years, more than 50 clinical trials have evaluated the effects of soy foods and supplements on the alleviation of hot flashes. Compiling the best ones together, the placebo groups got about a 20% drop in hot flash severity, the soy groups achieved about a 45% drop. So on average, the soy did
about 25% better than control. There have been two studies that
compared soy phytoestrogens head to head against hormones. And in one study, they actually
seemed pretty comparable, in terms of reducing hot flashes, muscle and joint pain, and vaginal dryness, compared to placebo, though in the other, soy did better than placebo, but estrogen and progesterone
therapy did better than both. But the soy has the benefit of not increasing cancer,
heart disease, and stroke risk.


  • Reply -a-VEnGeANce January 3, 2018 at 1:00 pm

    People who argue that soy raises estrogen levels and causes feminization in men because quote: "They use soy as treatment for menopausal women" need to do their research before they continue to embarrass themselves. It's superiorly annoying.

  • Reply AlboPepper - Drought Proof Urban Gardening January 3, 2018 at 1:05 pm

    Soy to the rescue! Thanks Dr Greger. 😀

  • Reply Good Taste and Grace January 3, 2018 at 1:13 pm

    Greatly reducing caffeine stopped my hot flashes. 😊

  • Reply Vegan Walk January 3, 2018 at 1:24 pm

    I wonder if telling people they're going to get diseases from eating animals has a placebo effect, I've been trying…

  • Reply Vegan Grandmaw January 3, 2018 at 1:28 pm

    When I started having hot flashes, I started eating tofu and using plain soy milk with no additives (found it at Trader Joe's) and my hot flashes went away.  When I would decrease the tofu, the hot flashes came back.  Eating soy worked for me!  Now 14 years later, I still eating and drink it regularly and so far no cancer, heart disease, etc.

  • Reply Quran Now January 3, 2018 at 1:35 pm

    Also fenugreek , salvia , fennel , cumin … etc contain estrogens.
    Soy may be harmful because it is genetically modified

  • Reply Daisy Jo January 3, 2018 at 2:05 pm

    Sad that you left out the top 3 diseases the Natural Estrogen prevents . The reduction in Horse estrogen is the key . The top 3 diseases are way scary hen Estrogen from Natural sources💕It’s NOT about JUST Hotflashes Ladies!

  • Reply Maple Flavor January 3, 2018 at 2:40 pm


  • Reply Kathryn Davis January 3, 2018 at 2:54 pm

    OMG I was just wondering about this the other day

  • Reply Sheryl Krupat January 3, 2018 at 3:15 pm

    During perimenopause I drank 2 soy milk smoothies every day to alleviate hot flashes. It worked really well.

  • Reply Lynn Lynn January 3, 2018 at 3:39 pm

    Soy should only be eaten after it is fermented.

  • Reply Melied Baez January 3, 2018 at 3:39 pm

    to bad I'm allergic 🙁

  • Reply Hannah January 3, 2018 at 4:25 pm

    Put it to the test

  • Reply Falafelzebub's Den of Vegan Iniquity January 3, 2018 at 4:28 pm

    Menopause is perfectly natural. But what do most women do? Run straight to the doctor for a prescription for horse pee, double their cow milk consumption, and spread negative propaganda about the humble soy bean. Sally Fallon must be very proud.

  • Reply Eelke Aptroot January 3, 2018 at 5:32 pm

    Something women should know about !

  • Reply Demiseem Demiseem January 3, 2018 at 6:10 pm

    So they soy had the benefit of not increasing cancer risk (as mentioned at the very end of the video), but soy raises IGF-1 levels and that in itself increases risk of cancer, correct? Anyone want to explain? Thanks

  • Reply dannywithnuggets January 3, 2018 at 8:20 pm

    He made no comment on the effects of soy on males. Whether or not soy is detrimental to the production of testosterone cannot be supported by anything presented in the video.

  • Reply Laura Sand January 3, 2018 at 8:56 pm

    Hey. I’m only 19 and I suffer from really really bad hot flashes. It started after I started taking ADD and anti depressants medicine. Do you think that eating more soy could help on this? I’m already eating a plant based diet. I have asked my doctor and psychiatrist, but they said that all there was to do is chance medicine, but this is the first medicine that has worked, and I don’t want a relapse.

  • Reply Tristan Devereaux January 3, 2018 at 10:16 pm

    That thumbnail made me sooo hungry for some fresh edamame.

  • Reply shean7890 January 3, 2018 at 11:34 pm

  • Reply Zheeraffa1 January 4, 2018 at 12:38 am

    There's recently been a soy "milks" test in a TV where I live, and apart from criticizing the commercial products for being way overprized and heavily watered down, a nutritional specialist from a military-run university (I could imagine that the military would be highly interested in sound science to keep its soldiers in good health) warned that the phytoestrogens, while being beneficial to menopausal women, might not be the best thing in kids' diet.
    Has there been a study about soy phytoestrogens' impact on child development? Especially keeping in mind that study of frogs turning intersex upon exposure to phytoestrogens washed down from parks and gardens? While humans may not have mechanisms to actually change their sex (unlike some amphibians and fish), it doesn't mean an exposure to certain chemicals couldn't wreak havoc.

  • Reply coco cocoposts January 4, 2018 at 12:53 am

    Steaming edamame now. Thanks!

  • Reply Jared Prymont January 4, 2018 at 12:54 am

    Can you do a 'how soy affects men' video? It'd be interesting to see if it cures MENopause. 🙂

  • Reply Jean C January 4, 2018 at 3:06 am

    Thank you, Doctor <3 It sucks there is so much ignorance and misinformation/understanding about soy !!

  • Reply Kathy Fausett January 4, 2018 at 7:45 am

    So, placebo 20% and soy 40%.  Isn't half of that 40% also placebo?  Nobody mentions the fact that even if you're getting the "real" pill, it is also having a placebo effect.  I never understood why placebos were used in the first place, since they're not really inert,  Why not just compare the soy group to a non-soy group? That way you avoid any complications.

  • Reply Alec Rodriguez January 4, 2018 at 9:18 am

    Soy boy here

  • Reply A J January 4, 2018 at 11:03 am

    What about hot flushes?

  • Reply Dimy Ssg January 4, 2018 at 11:30 am

    True! Plant based diet helped me with symptoms related to menopause. I have increased soy products in the past two years and it really does work:)👍🏼

  • Reply 1121gsm January 4, 2018 at 12:20 pm

    "Drinking a glass of soy milk with each meal can cut estrogen levels in half." ??? I had always understood that soy products increase estrogen and that's why men should avoid soy. Can somebody help me out here. Which is true?

  • Reply Madame Traffic Jam January 4, 2018 at 12:27 pm

    I want "Put it to the test!" on a mug.

  • Reply ZENNology of Everything January 4, 2018 at 10:46 pm

    So how much sojamilk to drink? (How much ng/l soya should be in drink)

  • Reply ZENNology of Everything January 4, 2018 at 11:11 pm

    So what is best? Soy protein powder? Soymilk? Beans?

  • Reply Hans Killuminati January 5, 2018 at 3:05 pm

  • Reply Dameon Barney January 5, 2018 at 5:36 pm

    Can you do a video about this? Specifically the iron and zinc part. The studies are in the description.

  • Reply EliasAlucard January 6, 2018 at 4:39 pm

    I'm male, and I'm a big believer in soy phytoestrogens, in fact, even my multivitamin supplement contains 40 mg soy isoflavones, great stuff!

  • Reply hacker halted January 9, 2018 at 7:53 pm

    Can men/male consume Soy milk without any potential health risks such a breast development. I have not found any clear cut answers. Can anyone help answer this?

  • Reply Maria Luiga January 18, 2018 at 8:28 am

    Could you do a video on tahini (sesame seeds) and phytoestrogens for women under 50? Also maybe look into the factor of Asian food culture and their use of phytoestrogen rich foods vs their health (more specifically women under 50)?

  • Reply Cammi Eklund January 24, 2018 at 9:31 am

    Why do I GET hotflashes from soy??

  • Reply The wise one me February 18, 2018 at 10:13 pm

    I thought soy wasn't good for you because it's %100 gmo.

  • Reply Sherry Ament March 28, 2018 at 7:50 pm

    I am 51, I eat a vegan whole food diet and still had CRAZY bad hot flashes until adding additional soy milk now they are really gone. My question is does the benefits change when soy milk is heated?

  • Reply Lizzie Clay April 8, 2018 at 7:25 pm

    Dr Greger, are you saying it’s better to take or eat the soy than to take progesterone?

  • Reply MLD-RN 1974 April 11, 2018 at 12:25 am

    Great news bc I love tofu!!!!!

  • Reply ChunkyStyle22 August 22, 2018 at 10:01 pm

    My symptoms were TERRIBLE until I added soy milk to my smoothies….it worked SO well.

  • Reply Garden Girl September 18, 2018 at 3:19 pm

    I’m in my mid 30s, WFPB, gluten free, caffeine free and still getting night sweats (have had them over a decade). Searching for answers.

  • Reply T. B. October 27, 2018 at 11:47 pm

    Thank you Dr. Greger for all of your hard work, and thank you Most High for making such wonderful things for us…And also…why aren’t we studying the power of placebos?

  • Reply Gary McKinnon November 9, 2018 at 4:29 pm

    Flashes, flushes it's horrible apparently. Gonna get ma girl on the beans!

  • Reply Derpy Wolfie April 11, 2019 at 4:28 am

    Soy give me arthritis. As soon as I eat anything with soy my arthritis comes back.

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