Might flax seeds (ALA) increase prostate cancer risk?

There are a lot discussions and articles online about the supposed connection between flax seeds (ALA) and prostate cancer – suggesting that more flax consumed = increase chance of prostate cancer. I haven’t found this issue addressed on your website (sorry if I missed it). Can you comment? Thanks!

DSikes / Originally posted below Just the Flax, Ma’am

Answer:

The latest meta-analysis of prospective studies found that, if anything, alpha-linolenic acid (ALA, the omega-3 fat in flax) was protective against prostate cancer. Men consuming more than 1.5 g/day appeared to have significantly lower risk (the amount found in about a tablespoon of ground flax seeds).

One of the reasons there’s been so much conflicting data is that ALA is found in great foods (dark green leafies) and less than great foods (meat), and so ALA intake is not necessarily a marker of healthy eating. What you want is a randomized controlled study of men with prostate cancer. Give half of them flax and see what happens. And that was done! (full text here)

Researchers at the University of Texas Anderson Cancer Center took a bunch of men with prostate cancer about a month before they were to go into surgery. Half were put on a few tablespoons of ground flax a day and after surgery their cancerous prostates were examined. The proliferation rates of the cancer in the flax-eaters were only half that of the controls, confirming the test-tube studies done on prostate cancer cells suggesting that flax can indeed slow prostate tumor growth.

For more on the effect of flax nutrients see videos such as:

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Michael Greger, M.D., is a physician, author, and internationally recognized professional speaker on a number of important public health issues. Dr. Greger has lectured at the Conference on World Affairs, the National Institutes of Health, and the International Bird Flu Summit, testified before Congress, appeared on The Dr. Oz Show and The Colbert Report, and was invited as an expert witness in defense of Oprah Winfrey at the infamous "meat defamation" trial. Currently Dr. Greger proudly serves as the Director of Public Health and Animal Agriculture at the Humane Society of the United States.

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Joe

Table 11 of veganhealth.org’s Omega-3 article at http://www.veganhealth.org/articles/omega3
says that the Nurse’s Health Study found that more than 1.25 – 1.5
grams per day of ALA can possibly cause eye problems. One tablespoon of
flaxseeds contains of 1.6 grams of ALA (see Table 8). So taking just
one tablespoon of flaxseed a day could
possibly be dangerous to your eyesight, unless flax is exempt from the
Nurses Health Study findings. So is flax exempt from those findings?
Derrek

I was wondering if anyone knew of anything to help with dandruff. I have a dry flaky scalp, and not sure if it is eczema, seborrhea dermatis or etc.

I know people recommend that this suggests a lack of omega 3′s. I have trying to eat 2 tablespoons of flax seed a day and have also been taking two vegan omega 3 supplements. Do I need both EPA and DHA and how much should I be consuming per day?

Might flax seeds (ALA) increase prostate cancer risk?

Answer:

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