June 3rd, 2011
03:51 PM ET

How much is too much phytoestrogen?

Every weekday, a CNNHealth expert doctor answers a viewer question. On Friday, it's Dr. Melina Jampolis, a physician nutrition specialist.

Asked by Keyana of Spokane, Washington:

I have two questions. What is considered to be a high/harmful amount of phytoestrogen in a woman's diet per day? And should a woman who has had cancer not take estrogen replacements or eat a diet high in phytoestrogens?

Expert answer:

Hi, Keyana. These are interesting questions. I'm going to assume that you are talking about breast cancer since the association of phytoestrogen consumption and breast cancer risk is the most concerning to many women.

Phytoestrogens are plant-based compounds that act like the hormone estrogen. There are two basic types of phytoestrogens: isoflavones and lignans.

Soy products are the most common source of isoflavones, and the controversy surrounding cancer and phytoestrogens are related to soy products. To provide you with the best possible response to your question, I turned to noted cancer nutrition expert Rachel Beller, who addresses this question on a regular basis at the Beller Nutritional Institute in Los Angeles.

Beller explained that while phytoestrogens are similar to human estrogens, their effect on human estrogen levels has not been well-researched because plant estrogens are 1,000 times weaker than the estrogen produced in our bodies.

Many studies suggest that soy isoflavones' estrogen-like effects are probably too weak to have any significant consequence on breast tissue in healthy women - that includes breast cancer survivors.

Regarding the association with breast cancer, Beller points to a 2011 study published in Cancer Epidemiology, Biomarkers & Prevention that found soy to be safe and favorable, even for breast cancer survivors, when eaten in its natural, unprocessed state - for example, tofu, tempeh, edamame, miso soup.

In fact, experts agree that fermented soy (miso, tempeh) is good for you. The fermentation process alters the chemical makeup of soy, which reduces the level of isoflavones by as much as 300%.

Therefore fermented soy foods have three times less of the chemical in question.

While this study does not conclusively establish the safety of soy, phytoestrogens aside, soy is not only an excellent source of heart healthy plant-based protein, which is encouraged in the latest dietary guidelines for Americans, it also contains dozens of nutrients that also appear to help fight cancer development.

These nutrients can protect cells from becoming damaged, encourage faulty cells to die instead of reproducing, regulate cell growth and even improve cell communication. These are all things that help strengthen your body against cancer and heart disease.

A study has also shown that consumption of soy early in life may help protect against breast cancer later in life, even if it may be more questionable for post-menopausal women.

What's also noteworthy is that Asians have been eating soy foods in large amounts for centuries, and their traditional soy-rich diets are associated with lower risks of breast and prostate cancer than Western diets.

Beller goes on to say that the "bad rap" that soy's been getting is due to the fact that when we hear something's "good for you," we process it to the max, extract the good stuff and concentrate it, which basically makes it lose its original identity.

Skip the processed soy foods and supplements, especially if you have a history of breast cancer.

The bottom line: If you have no history of breast cancer, there is no known high or harmful amount of phytoestrogens, and foods such as unprocessed soy are an important part of a healthy diet.

If you have a history of breast cancer, as with nutrition in general, you should not focus on a single food or nutrient. The key is moderation.

The phytoestrogens consumed by eating moderate amounts of relatively whole and unrefined forms of soy foods (two to three times a week) can be considered part of a healthy, complete diet.

Regarding estrogen replacement therapy, according to the National Cancer Institute, "Studies of hormone use to treat menopausal symptoms in breast cancer survivors have produced conflicting results," so I suggest speaking with your physician to determine the best approach for you.

Follow Dr. Jampolis on Twitter

soundoff (924 Responses)
  1. Camper Repairs Near Me

    You should take part in a contest for one of the finest blogs on the internet. I most certainly will highly recommend this blog!


    June 19, 2021 at 21:14 | Report abuse | Reply
  2. Sprinter Repair Near Me


    June 19, 2021 at 21:22 | Report abuse | Reply
  3. Sprinter Repair Shop Near Me


    June 19, 2021 at 22:31 | Report abuse | Reply
  4. RV Repair Mission Viejo


    June 20, 2021 at 00:05 | Report abuse | Reply
  5. RV Repair Shop Near My Location


    June 20, 2021 at 00:09 | Report abuse | Reply
  6. Google Marketing Business


    June 20, 2021 at 06:20 | Report abuse | Reply
  7. Local Marketing Agencies


    June 20, 2021 at 06:42 | Report abuse | Reply
  8. Myron Taverner

    Hi, check this product that can help to take care of your hair: https://bit.ly/3gJqhQH


    June 20, 2021 at 06:47 | Report abuse | Reply
  9. Otha Zorns


    June 20, 2021 at 16:10 | Report abuse | Reply
  10. Norah Higgin


    June 20, 2021 at 18:04 | Report abuse | Reply
  11. Frances Sitzler

    Hello, I do think your web site could be having browser compatibility issues. When I look at your website in Safari, it looks fine however, if opening in I.E., it's got some overlapping issues. I merely wanted to provide you with a quick heads up! Apart from that, excellent blog!


    June 20, 2021 at 20:31 | Report abuse | Reply
  12. emergency room near me

    Great post. I'm facing some of these issues as well..


    June 21, 2021 at 03:03 | Report abuse | Reply
  13. lidl near me


    June 21, 2021 at 04:55 | Report abuse | Reply
  14. Camper Repair Places Near Me

    I'm very pleased to uncover this great site. I need to to thank you for your time for this particularly wonderful read!! I definitely liked every part of it and I have you bookmarked to check out new stuff in your website.


    June 21, 2021 at 06:56 | Report abuse | Reply
  15. fedex store near me

    Iím amazed, I have to admit. Seldom do I encounter a blog thatís both educative and interesting, and let me tell you, you've hit the nail on the head. The issue is something that not enough men and women are speaking intelligently about. Now i'm very happy I came across this in my search for something concerning this.


    June 21, 2021 at 08:51 | Report abuse | Reply
  16. chevy dealer near me


    June 21, 2021 at 12:17 | Report abuse | Reply
  17. RV Repair Parts Near Me

    Aw, this was a really good post. Finding the time and actual effort to make a really good articleÖ but what can I sayÖ I procrastinate a lot and never seem to get nearly anything done.


    June 21, 2021 at 17:48 | Report abuse | Reply
  18. Shawanda Hovda



    June 21, 2021 at 19:44 | Report abuse | Reply
  19. Sprinter Door Rust Repair


    June 21, 2021 at 19:50 | Report abuse | Reply
  20. https://topphimhot.net

    Best view i have ever seen !


    June 21, 2021 at 21:00 | Report abuse | Reply
  21. auto detailing near me

    Hi there, There's no doubt that your website could possibly be having internet browser compatibility problems. Whenever I take a look at your blog in Safari, it looks fine however when opening in IE, it's got some overlapping issues. I just wanted to provide you with a quick heads up! Aside from that, fantastic blog!


    June 21, 2021 at 22:22 | Report abuse | Reply
  22. RV Repair Orange County

    I needed to thank you for this good read!! I certainly loved every little bit of it. I have you book marked to look at new stuff you postÖ


    June 21, 2021 at 22:36 | Report abuse | Reply
  23. Collision Repair

    Saved as a favorite, I love your site!


    June 22, 2021 at 00:18 | Report abuse | Reply
  24. RV Repair Near Me


    June 22, 2021 at 03:50 | Report abuse | Reply
  25. RV Repair Shop Near Me


    June 22, 2021 at 09:34 | Report abuse | Reply
  26. Mercedes Sprinter Repair Panels

    This is a topic which is close to my heart... Best wishes! Exactly where are your contact details though?


    June 22, 2021 at 15:20 | Report abuse | Reply
  27. pharmaceptica

    topical erectile dysfunction https://www.pharmaceptica.com/

    June 22, 2021 at 16:10 | Report abuse | Reply
  28. Social Media Marketing Businesses Near Me


    June 22, 2021 at 17:29 | Report abuse | Reply
  29. last podcast on the left reddit

    After looking into a few of the blog posts on your blog, I truly appreciate your technique of blogging. I book-marked it to my bookmark site list and will be checking back soon. Take a look at my website too and tell me your opinion.


    June 22, 2021 at 20:09 | Report abuse | Reply
  30. Internet Marketing Business

    An intriguing discussion is definitely worth comment. I do think that you need to write more about this topic, it might not be a taboo subject but typically people don't talk about such issues. To the next! All the best!!


    June 22, 2021 at 21:51 | Report abuse | Reply
  31. Internet Marketing Firms

    An impressive share! I have just forwarded this onto a co-worker who has been conducting a little homework on this. And he actually bought me dinner simply because I stumbled upon it for him... lol. So let me reword this.... Thank YOU for the meal!! But yeah, thanx for spending some time to talk about this subject here on your site.


    June 22, 2021 at 22:14 | Report abuse | Reply
  32. Digital Marketing Agencies Near Me


    June 22, 2021 at 22:22 | Report abuse | Reply
  33. podcast review

    Everything is very open with a very clear explanation of the issues. It was truly informative. Your site is useful. Thanks for sharing!


    June 22, 2021 at 23:31 | Report abuse | Reply
  34. Social Media Marketing Near Me

    Iím impressed, I must say. Seldom do I come across a blog thatís both equally educative and engaging, and without a doubt, you've hit the nail on the head. The issue is something too few men and women are speaking intelligently about. Now i'm very happy that I found this during my search for something concerning this.


    June 22, 2021 at 23:34 | Report abuse | Reply
  35. Internet Marketing Consultant


    June 23, 2021 at 00:14 | Report abuse | Reply
  36. RV Brake Repair Near Me

    This site truly has all of the information and facts I wanted about this subject and didnít know who to ask.


    June 23, 2021 at 00:22 | Report abuse | Reply
  37. Content Marketing Consultants


    June 23, 2021 at 01:00 | Report abuse | Reply
  38. RV Refrigerator Repair Near Me

    Way cool! Some extremely valid points! I appreciate you writing this write-up and the rest of the website is also really good.


    June 23, 2021 at 02:03 | Report abuse | Reply
  39. RV Sales And Repair Near Me

    Everything is very open with a really clear description of the challenges. It was definitely informative. Your site is extremely helpful. Many thanks for sharing!


    June 23, 2021 at 06:21 | Report abuse | Reply
  40. penumbra podcast

    bookmarked!!, I love your site!


    June 23, 2021 at 06:59 | Report abuse | Reply
  41. 24 Hour RV Repair Near Me


    June 23, 2021 at 13:21 | Report abuse | Reply
  42. RV Electrical Repair Near Me

    You have made some decent points there. I checked on the internet for additional information about the issue and found most individuals will go along with your views on this website.


    June 23, 2021 at 13:52 | Report abuse | Reply
  43. tanning near me

    Good web site you've got here.. Itís difficult to find quality writing like yours these days. I seriously appreciate individuals like you! Take care!!


    June 23, 2021 at 15:25 | Report abuse | Reply
  44. Local Marketing Business

    This is the perfect site for anyone who really wants to understand this topic. You understand a whole lot its almost tough to argue with you (not that I actually would want toÖHaHa). You definitely put a new spin on a subject that's been written about for ages. Wonderful stuff, just wonderful!


    June 23, 2021 at 16:29 | Report abuse | Reply
  45. Local Marketing Agencies


    June 23, 2021 at 16:59 | Report abuse | Reply
  46. RV Windshield Repair Near Me

    Greetings! Very helpful advice in this particular post! It is the little changes that will make the most significant changes. Thanks for sharing!


    June 23, 2021 at 17:35 | Report abuse | Reply
  47. SEO Marketing Firm


    June 23, 2021 at 17:41 | Report abuse | Reply
  48. SEO Marketing Consultants


    June 23, 2021 at 18:11 | Report abuse | Reply
  49. Social Media Marketing Firms Near Me

    You are so interesting! I don't believe I have read through anything like this before. So wonderful to find another person with some unique thoughts on this subject matter. Seriously.. many thanks for starting this up. This web site is something that is needed on the web, someone with a bit of originality!


    June 23, 2021 at 18:41 | Report abuse | Reply
  50. Social Media Marketing Companies

    The very next time I read a blog, I hope that it won't disappoint me just as much as this one. After all, I know it was my choice to read through, but I really believed you would have something useful to say. All I hear is a bunch of moaning about something you could possibly fix if you weren't too busy searching for attention.


    June 23, 2021 at 18:52 | Report abuse | Reply
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19

Leave a Reply to New Forklift Tires California


CNN welcomes a lively and courteous discussion as long as you follow the Rules of Conduct set forth in our Terms of Service. Comments are not pre-screened before they post. You agree that anything you post may be used, along with your name and profile picture, in accordance with our Privacy Policy and the license you have granted pursuant to our Terms of Service.

About this blog

Get a behind-the-scenes look at the latest stories from CNN Chief Medical Correspondent, Dr. Sanjay Gupta, Senior Medical Correspondent Elizabeth Cohen and the CNN Medical Unit producers. They'll share news and views on health and medical trends - info that will help you take better care of yourself and the people you love.