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  • Thanks for this video. I’ve just started adding flax seeds to my diet for the omega acids, but it is good to know that they have all sorts of other benefits as well! Also, I have been eating them whole, but I will grind them up this afternoon and stick them in the refrigerator.

    • Michael Greger M.D.

      Great! I recommend two tablespoons a day.

      • chewbella

        so i should take 2 Tablespoons of pre-ground flaxseed daily for the long term?any possible negatives to doing this?

    • Joel

      Amy, Take it a small step further: Grind the seeds fresh each time you use them! This is nothing – 6 seconds in your coffee grinder. You know flax contains a lot of oil – delicate oil. So refrigerated or not, the exposed oil in ground seeds is becoming rancid at a faster rate (probably much faster) than it would by remaining sealed in the seed. Weighing this against the tiny inconvenience of grinding the seeds fresh is no contest in my opinion. Two NDs I’ve seen concur with this. Take it another step further and store the whole seeds in the refrigerator if you have a large quantity and are using them relatively slowly. Oil is oil.

      • Michael Greger M.D.

        Surprisingly, ground flax seeds actually do suprisingly well–see my response to jmerrikin below.

        • Martin

          If I daily make my own bread, and I add the daily dose of flax seeds wheet to it, will the good nutrients in flax be destroyed by cooking the bread in the oven?

  • jmerrikin

    Dr. Greger, thank you for this information. My question is — I have been purchasing and consuming about 2 tbsp. per day of Bob’s Red Mill ground flax seed in a package. Is this as beneficial to my body as grinding my own whole flax seeds and storing them in the refrigerator?

    • Michael Greger M.D.

      While I enjoy talking dietary theory as much as the next nutrition nerd, my favorite questions are the practical ones like this one–thank you for asking! I’m sure bunches of other people were wondering the exact same thing, so you taking the time to ask helped them all.

      Pre-ground is perfectly fine. In an air-tight container (dumping the bag contents into a jar, or tupperware, or maybe the bag has a built-in ziplock?) it should last for months just fine in the fridge (but it shouldn’t last for months because you’re so awesomely eating 2 tablespoons a day! :)

      • lalov1

        I leave mine out in a zip-lock bag. Should I be putting them in the fridge?

      • That’s the answer I have been looking for. Thanks.

      • I came to your site wondering the *exact* same thing. We started taking flax bc of your video about vegans still having heart disease in part bc of the absence of flax. So I’ve been growing increasingly concerned about whether the ground flax from Bob’s Red Mill is doing the job. My only remaining concern is: how do we know whether the ground flax might have already been on the shelf longer than “months”? The bags are sold in protective covering (basically light protective yellow or white bag). Then the instructions say to store them in the fridge, which we always do, in a Ziploc bag. Do you still think everything is fine, even if the bag might have sat on the shelf for months before we purchased it?

        Thanks for all of your great nutritional videos! Love them!

      • baggman744

        buying ground flax is as good as grinding whole seeds?

        • Joan E- NF Volunteer

          Whole flax seed doesn’t really get digested. To obtain the benefits, it needs to be ground. However, once ground, it will go rancid faster, so it should be stored in the fridge or freezer. In terms of freshness, it is better to buy whole flax and ground when you are ready to use.

          ground vs whole flax

          • baggman744

            Like how fast? My Bob’s Red Mill ground flax has an expiration date nearly a year from now. Thank you kindly for the reply.

          • Joan E- NF Volunteer

            From what I have seen, 6 months. But it depends on where you are storing it. Keeping in the fridge or freezer will extend the shelf life.

  • jmerrikin

    Thank you Dr. Greger.

    What is it about flax seed that requires storing it in an “air tight” container? Does flax seed lose any potency or benefit when it is exposed to room temperature air? How about heat? I usually add my 2TBSP of ground flax seed to my hot steel cut oats in the morning but now I am wondering if putting it in the hot oatmeal is compromising it’s beneficial properties.

    Thanks again for your great work! You have helped to save my life and many others!

    • Michael Greger M.D.

      Jmerrickin–the high omega 3 content makes them susceptible to oxidation once the protective outer coating has been breached by grinding, so best to put it in something with a lid. No worries about the heating though. The Canadian flax council (though certainly not unbiased) found that one could cooked ground flax at the equivalent of 350 degrees Fahrenheit for a full hour and still not see a decrement in alpha-linoneic acid content (the omega 3 it’s packed with). Even more importantly, is the secoisolariciresinol diglucosides (the lignans! Other foods have omega 3’s but the magic of flax is in these anti-cancer lignan compounds). Research found that they survive cooking fine as well. If you make some flax muffins, though, the deal is you have to send me one :)

  • What about keeping the ground in the freezer? This is what I read to do, but maybe I’m doing it wrong.

    • Michael Greger M.D.

      Cute little flaxicles! :) Sounds good to me. I haven’t seen any science on it but my guess would be they might even last a little longer that way. Thanks for the question Jennifer. For more facts-on-flax check out these other videos.

    • Calvin Burr

      The one thing I always keep in mind with respect to freezing is that Vitamin E is the one vitamin that is destroyed by freezing. So I’m reluctant to freeze nuts and seeds for that reason. However, freezing is better than allowing rancidity to occur.

  • GreenVegan

    what happen to flax seed if stored at room temperture.. and if the temperature increases to 90 degrees +. should i discard?

    • Michael Greger M.D.

      No problemo, GV. See my response to Jmerrickin above.

  • LouiseF

    I saw Flax oil supplements today in the vitamin section. Although I am happy putting ground flax seeds on my oatmeal, my boyfriend doesn’t like the taste and won’t do it. Are these capsules then a good option for people like that?
    Thank you!!

    • jmerrikin

      My guess is that the flax seed oil may give you the omega-3 EFAs but you will miss out on the ever important fiber.

      As a tip, I mix a tbsp into my oatmeal and cannot even tell it’s in there. I also frequently add it to my salad dressings and still cannot taste it.

      I am wondering if your boyfriend got a taste of some flax seed that had gone rancid and that is what turned him off to it.

  • I mix ground flax seeds with a little water and use as an egg replacer in baking! Works really well and makes my vegan muffins even better!

  • There is a new product on the market called Flax Milk that touts 1100 miligrams of Omega 3 & 50 calories to 8 ounces. What do you think of this? Is drinking it as good as eating flax seeds?

    • Joel

      Melanie, What ingredients, and in what proportion, are listed on the label? How can you ask, “What do you think of this?” when you haven’t said what “THIS” is? The title “Flax Milk” says practically nothing.
      Larger advice: read ALL labels if you buy food in packages and educate yourself enough to know what each ingredient is. If you don’t know don’t buy it, or research the unknowns before buying it. An impulse is not really a decision.

      • LauraR

        Joel, why so preachy to Melanie? She read the label enough to know it contains 1100 mg of Omega 3, and 50 calories in 8 oz. Also, she DID say what it was, Flax Milk. That’s what the manufacturer puts on the label, so you might want to jump on them instead. It’s actually made from cold pressed flaxseed oil. Also, Melanie didn’t even say she bought the Flax Milk, so saying “an impulse is not really a decision” is inaccurate at worst and condescending at best. Flax Milk is made from cold pressed flax oil, by the way.

  • becochic

    If flax affects estrogen, then is it safe to eat while pregnant? It should be fine while breastfeeding since estrogen is naturally low, but I don’t know if I want to inhibit estrogen while pregnant… Do you have any more information on this? I’ve looked online and I can’t find any studies. It sounds like flax seeds provide great stuff for a growing fetus, so it seems like a shame to cut them out.

    • Animal studies involving rats do suggest that flax affects the offspring of pregnant rats. These sorts of experiments do tend to look at relatively high levels of consumption of whatever variable they’re looking at, and anecdotally (as opposed to scientifically) there are women who report using a small amount of flax throughout their pregnancy without any ill effects to themselves or their babies. However, estrogen isn’t the only hormone affected by flax . Studies on postmenopausal women show an effect on prolactin too – which is why flax is also not recommended during breastfeeding. Therefore it might therefore better to err on the side of caution and go easy on the flax during pregnancy and breastfeeding. Focus instead on a balanced whole foods diet to ensure the health of yourself and your baby. It’s as much about what you choose to eat and what you leave out of your diet and there are alternative plant sources of omega 3s for example (see good and bad fats: It’s natural to take as much care as you can during pregnancy, but you may be surprised at how sometimes this can be counterproductive. In case you were tempted to supplement with iron during your pregnancy, take a look at

      • becochic

        Well, I’ve been drinking soy for a week now and having a tablespoon of flax and I haven’t noticed any difference in my milk supply. My baby is ten months already so I do seem to be very well established, too.

        I’ve been low on B12 and anemic for a long time. And I have hypothyroidism. I am worried about soy affecting my hashimoto’s disease and t4 absorption from my medicine…
        Then, I am wondering if I have gastro issues.. “leaky gut” issues, because I ate tons of meat and dairy before and was always low on b12 and iron and who knows what else.

  • how much grounded flax seed can one consume in a day?

    • Flaxseeds are indeed a superperformer (and as if you needed further proof, check out this video comparing flax to chia seeds But the first question to ask is how much ground flaxseed you are consuming already. As with any supplement, it’s a good idea to build up to the recommended dose gradually to give your body the chance to adjust. In the case of flaxseed, go from say, a teaspoon a day to a tablespoon a day. You shouldn’t need more than two tablespoons. Although flaxseed is a food, it’s not good to overdo any one food. The golden rule is to supplement any nutrient by the minimal amount that is effective.

      Flaxseeds provide Omega-3 fatty acids of course (see but also protein, minerals, lignans and lots of fiber. And if you are eating a whole-foods diet high in plants, remember you may be getting these nutrients already.

      Well done on consuming flaxseeds ground up by the way – that’s definitely best for digestion. And don’t forget to always take enough water on board to help process the fiber!

    • Michael Greger M.D.

      Bo’s got a great point about the water. May also not want to go over 4 TB of raw flax a day so as not to not interfere with thyroid function (

      • Joshua Pritikin

        The video you linked discusses an enzyme blocking iodine uptake. So I guess this isn’t a concern for cooked, ground flax since the cooking process should destroy any enzymes.

  • DSikes

    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!

    • Michael Greger M.D.

      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.

  • DSikes


  • soupy

    Finding a tasty way to eat my daily ground flax has been a challenge until I tried this: mash together 2 tablespoons ground flax with 2 teaspoons strawberry (or your favorite) preserves and spread on a piece of whole grain toast. It also tastes good enough to eat by the spoonful, or mashed raspberries with a healthy sweetener can be substituted for the preserves. Bon appetit!

    • ghulstyle

      yum i gotta try that!

  • Vitamin-mE

    what do you think about this?
    and anything he has to say
    the company that makes this clary sage oil also say
    that flax oil is banned in France and Germany.
    Is this all true and what it’s all about?
    Thanks :)

  • Vitamin-mE

    And is this true that omega-3 disapears 15 min after grounding flax seeds? That’s what I heard from many vegans

    • Michael Greger M.D.

      Silly vegans! Ground flax can even be cooked for an hour without significant decrement in the omega-3 content. Just keep it in your fridge in an airtight container and it should last for weeks.

  • Seri

    I used to use flax seed until I was diagnosed with estrogen positive breast cancer. Then my oncologist told me to avoid flax seed because of its estrogenic properties. After listening to your video I am now confused about whether it would be better to use it or not. My cancer was found early and I did not need to have chemo. Can you comment on the relationship of flax to estrogen positive breast cancer? thank you!

    • Toxins

      Seri, people tend to get confused with phytoestrogens. Phytoestrogens do not raise estrogen levels. Did your doctor say to avoid soy products as well? All of these phytoestrogen rich plant foods have a positive affect in preventing breast cancer.

      • Seri

        Yes, my doctor did say to avoid soy products also. So I stopped eating flax and soy and ironically ate more dairy products for protein(I’m a vegetarian). It seems from what I’ve been reading on your website that this was not the best course of action for me.

  • chewy

    i am reading your post today about 3 tablespoons of flaxseed daily -ground or whole?

  • chewy

    is the 3 Tablespoons you mention to eat daily,do you mean 3T whole or pre-ground?

    • Toxins

      You would want it pre ground, unless you chew every seed thoroughly. If you swallow the seeds whole they will pass through your digestive system unused.

  • chewy

    is there anyone who should avoid eating ground flaxseed daily?

    • chewy

      any answer to this yet?currently  taking 2 Tablepoons of pre-ground flaxseed meal daily.

      • Toxins

         Hello again Chewy, as i mentioned before, pregnant women should avoid flaxseed use as it may increase the risk of a stillbirth.

        • Brigitte

          Hi Rami! Please, can you cite the studies that conclude this? Thanks a lot?

          • Rami_RD2B

            HI Brigitte, I honestly don’t remember where this is from. Im not sure if it is accurate still or has been disproven. It appeared in an older video and was briefly mentioned. I am not entirely sure where though. My comment above was from 3 years ago, so my memory is fuzzy.

          • Brigitte

            HI Rami, thanks for your answer.
            In this 3-years-old video, Dr Greger talks of preterm delivery in preliminary data:
            So, I’mean looking for confirmation (or not!).

          • Joseph Gonzales R.D.

            Dr. Greger does mention, perhaps just as a precaution based on one study, but nonetheless a huge red flag, that women in the last two trimesters of birth should considering avoiding it.

  • I have suffered with dry flaky skin on my elbows for years (an undiagnosed combination of psoriasis and eczema). For some reason, I took a heaping spoon of flax seed at night, and the next morning, while touching my elbows, I noticed that the flaky skin was entirely gone – and that the skin around the elbows was silky smooth. In 50+ years, that has NEVER happened – even when the flaky skin cleared up. (It usually shows up when I have more than 2 pieces of bread.

    I wanted to share this – and I believe that this better outcome – which is continuing – is directly attributable to the flax. That day, which I made the fateful decision to have the flax – it was the only thing I changed in my diet.

    Now, from reading this column, I see that I should double down – and increase to 2 heaping tablespoons a day. Thanks lots!

  • I prefer chia seeds. Dr. G., how about a flax vs. chia? ;^)
    Chias seem to outdo the flax, but I’m not privvy to the latest info. Any chance of a video on it?

  • Michael Greger M.D.

    Also be sure to check out my associated blog post Breast Cancer and Diet!

  • Kartesrick

    This site is flat amazing. I am becoming nutrition wise in spite of all the misinformation that is out there.

  • lee

    What Ive Been Saying For Years Its Nice To Be Validated. If you are in the UK you can get them here

    Flax Hulls

  • Guest

    Does flax seed affect oral contraceptives? Either hormonally by changing estrogen amounts or by flushing medications out of your system from so much added fiber?

    • Toxins

       Phytoestrogens found in flax do not have a negative hormonal balance and actually are very healthy for you in preventing estrogen dependent cancers from developing.

      As far as fiber is concerned, yes flax seeds contain fiber but it is not the top source of fiber. Flax seeds are commonly advertised though to be very high in fiber but compared with other plant foods it doesn’t have early as much.

      Grams of fiber per 200 calories based on USDA nutritional database:


       chia seeds

      Dietary Fiber:


      Dietary Fiber:



      Dietary Fiber:
      kidney beans

      Dietary Fiber:

      navy beans Dietary Fiber:
      15g  split peas Dietary Fiber:
      15g  black beans Dietary Fiber:
      13g  pinto beans Dietary Fiber:
      13g  lima beans Dietary Fiber:
      Vegetables:Turnip Greens Dietary Fiber: 35g
      beet greens Dietary Fiber: 34gmustard greens Dietary Fiber: 33g
      artichokes Dietary Fiber: 32g
      cauliflower: Dietary Fiber: 32g
      eggplant: Dietary Fiber: 28
      romaine lettuce Dietary Fiber: 25g
      collards Dietary Fiber: 24g
      squash Dietary Fiber: 24


      Raspberries Dietary Fiber: 25gblackberries Dietary Fiber: 25g

      blueberries Dietary Fiber: 17g
      Asian pears Dietary Fiber:
      strawberries Dietary Fiber: 12

      consuming a high fiber diet is natural and healthy.

  • PeterK

    Any studies on … impacts of using the Microwave, 

    Breakfast for me –  2/3 cup Oatmeal add 2 tbsp ground Flaxseed, 1 tsp of AMLA powder, 1/2 tsp of Cinnamon  add water … THEN it goes in the microwave for 80 seconds top with a handful of blueberries 5-6 raspberries.
    Will try use a few more blackberries going forward.

    My Question: So is using the microwave going to diminish the value of the Flax, AMLA or the Cinnamon

    • Toxins

       Check out this video on the best form of cooking

      Microwaves will diminish antioxidants somewhat but there is currently no research to show that microwaving food in itself is harmful or contributes to a health epidemic.

  • Beej 2u

    I germinate my flax seeds overnight so they both soften and begin the sprouting process. Softening makes it easy to grind them into the smoothies I enjoy for breakfast.  The sprouting process breaks down the proteins into amino acids, the fats into fatty acids, and the complex carbohydrates into simple carbohydrates. These act as probiotics, becoming more easily available. In addition the sprouting process increases the amounts of enzymes in the flax.

    Enjoy good health!

    • Joshua Pritikin

      I’ve heard advocates of sprouting flax. Is there any science to back these claims up? Or is it pure speculation?

      • Joseph Gonzales R.D.

        There is data on sprouted flax, but I am not sure it’s necessary to sprout 100% of the time since research still shows benefits with straight flax. Just gotta grind it a bit so it does’t slip through the digestion process.

  • Pierre Pelletier

    Dr. Greger 
    how does the shelled hemp seed compare with flaxThank you for sharing

  • Judy

    Will flax seed help with hot flashes?

  • Daniel Dunér

    How about this claim on Wikipedia regarding neurotoxic and immunosuppressive properties of flax seeds?

    “Consuming large amounts of flax seed may … have adverse effects due to its content of neurotoxic cyanogen glycosides and immunosuppressive cyclic nonapeptides”

  • You’ve said in the comments that flax is not recommended for pregnant women, but what about women who are trying to get pregnant? Will this affect their fertility?

    • Toxins

      Consuming flax seeds does not have negative adverse affects on fertility. The concern with consuming flax seeds WHILE pregnant is that the risk of certain birth defects is higher.

  • Stan Kogan

    I believe the flax milk product that Melanie mentioned is made by Good Karma. They released a flax milk product that comes in three flavors: unsweetened, original, and vanilla. 

    Here’s a link to the unsweetened one: 

    The ingredient list is as follows:
    All Natural Flaxmilk (Filtered Water, Cold Pressed Flax Oil), Tapioca Starch, Tricalcium Phosphate, Canola and/or Sunflower Lecithin, Natural Flavors, Sea Salt, Guar Gum, Xanthan Gum, Carrageenan, Vitamin A Palmitate, Vitamin D2, Vitamin B12.  

    I’m very curious as to how this product compares to actual ground flax seeds because I consume both regularly. Personally, I find that this milk works well for smoothies and isn’t as creamy as coconut milk.

  • Emily

    Dr. Greger, what do you recommend for the women who have had many bladder infections? I have one about once a year, but I only treat them with antibiotics if home remedies aren’t working (normally home remedies work really well). Before I learned about natural remedies, I treated all of them with antibiotics… I’ve probably had ten or so rounds of antibiotics in the last five years– most for bladder infections, one round for strep throat. I am concerned about rebuilding my gut flora and wonder what I should do. Thanks for any info you have!

  • Crystal

    How many of these benefits are retained in flax milk? It’s creamy, delicious, and only 25 calories a glass. If it can do all the stuff outlined in your video, it will be even more perfect!

  • beangu

    I’ve been adding milled flax to my smoothies everyday and prefer it to the taste of ground flax which has the out shell – it makes my smoothies very rich and fatty tasting. I don’t have to add half a banana like I use to which means more berries! Is there any nutritional difference other than additional fiber in the ground flax?

  • MindbodyMD

    Wow! I never seize to be amazed at how much knowledge you pack into each video. Thank you so much for this excellent public service.

  • John C

    I have been advised to stop eating flaxseed because it causes indigestion and might make my acid reflux worse.
     However I notice my BPH is worse when I don t eat flax.
    Any solution here?

  • Stephen Albers

    I’ve heard flax can be toxic in moderately large doses.  Do you agree?  What is a maximum daily dose?

    • Toxins

      Flax does indeed cyanide like byproducts when consumed in large doses, but these large doses are not feasible unless one is eating several bags of flaxseed a day. Dr. Greger recommends 2 tablespoons of flax a day.

  • Rphiri

    Is there any problem of taking medications along side eating the ground flax seeds! 

  • Lor

    After watching this I’m going to add flax to my morning smoothies…if only to “add a day to my period”. What has me a bit bothered is that I suffer with pain (a 10 on the scale for me) once a month and realized it might be connected to my very short 24 day cycles. Maybe adding flax will give me another day, and cause the pain to curb. Im researching the connection to short cycles,pain,and estrogen-excess but I haven’t found much useful info.

  • While doing some research on flax seeds, I discovered that flax seeds are one of the richest sources of alpha-linolenic acid; however, I then found some research asserting that “Dietary α-Linolenic Acid Is Associated with Reduced Risk of Fatal Coronary Heart Disease, but Increased Prostate Cancer Risk.” (Journal of Nutrition)

    The study concluded that “the association between high intake of ALA and prostate cancer is of concern and warrants further study.”

    To quote Bugs, “What’s up, Doc?”

    • Toxins

      The study you present is a meta analysis looking at several studies. Specifically,  omega 3 from vegetable oils was looked at and not omega 3 from the whole food itself. Consuming omega 3 in the form of oils is not the healthful approach as all the vitamins, minerals, fiber and nearly all of the phytonutrients, including the anticancer lignans have been removed removed from the whole food when converted to oil.

  • Patrick

    Many thanks for your great videos. I have a question about flax seeds. SOme studies seems to show that only soaked flax seeds contain adequate nutrition and simply ground flax contains not much. Please refer to this article:

    The Hyprocates health institute also recommend to soak flax seeds for 24hr prior to eating as its the best way to extract their full potential.

  • Gemma

    Thank you Michael for this wealth of information.  I have a question on flax oil tea, which is a time old remedy for rehydration and for soothing the colon.  My query is in the preparation where you simmer the flax seeds for an hour in water.  Does this process produce a wonderful tea but contaminated with rancid oils?  Or does the water somehow protect from the oxidation/heat issues.
    Many thanks

  • Caitlin

    I really want to start taking flax every day but it seems like combined hormone birth control pills will completely negate the hormonal effects of flax. Does anyone know for sure if this is the case?

  • Paul

    I took flax for 2 months stopped it because I started to feel really low, depressed, felt better , took it again for 2 weeks and the same thing happened , felt depressed again, stopped it and felt better. It did relieve joint stiffness in my RA however, what a shame.

  • Elia

    I had ileostomy. My big bowel was removed. How flaxseeds would benefit me if, as I understood, they positively affect bacteria in the gut (which is now absent)?

    Also, if you sprinkle milled flaxseeds on something hot (e.g. porridge, stew), wouldn’t they lose their nutritional value from the heat?

    Many thanks, Elia

  • Dr. Greger, do you have any commentary on the potential dangers of consuming flax I found on its wikipedia page:

    “…..may have adverse effects due to its content of neurotoxic cyanogen glycosides and immunosuppressive cyclic nonapeptides”

  • Joe

    Vegan nutritionist Jack Norris’s article, “Omega-3s in Vegetarian Diets,” says that “Increasing ALA to 3 – 4 g/day has some concerns.” He wrote that “Three studies looking at age-related eye damage and fatty acids, all coming from the Nurse’s Health Study, have associated modest ALA intakes with age-related eye problems.” Mr. Norris qualified this by saying that the “The ALA in these studies came mostly from animal products that were likely cooked (omega-3s are easily oxidized by heating). It is not clear that the association is causal or if the causation would apply to uncooked ALA (i.e., from plants).” In a recent comment, he indicated that he doubts that the eye problems were caused by the ALA levels, but he seemed to stand by the concerns he expressed about ALA since he did not want to just dismiss the findings. The article and comments are at The article recommended vegans add just 0.5 grams of uncooked ALA to what they’d otherwise get without special planning.

    The recommendation above is to eat two tablespoons of flaxseeds daily. This amounts to consuming 3.2 grams of ALA. This appears to be at or above the level of ALA that the Nurse’s Health Study indicated might cause age-related eye problems.

    Dr. Greger, can you please comment? Thank you!

    • Mandy

      Table 11 of the Omega-3 article on 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, let alone two tablespoons, could possibly be dangerous to your eyesight, unless flax is exempt from the Nurses Health Study findings. So is flax exempt from those findings?

  • LuccaQ

    Sesame seeds are also a great source of lignans and are delicious. I alternate between sesame & flax.

  • Fidel Castrati

    The similarity in the words Flomax & flax is a synchronicity. Take the ouch out of Flomax (in terms of side effects as well as monetary price) and you get flax.
    Dr. Greger is quick with the literary devices. Would love to see an ad for flax where the Dragnet cop tells a woman “Just the flax, mam. Don’t let your husband take Flomax!” :)

  • Tracy

    So what about grinding my own Bob’s Red Mill flax seed and putting a TBSP or two into my green smoothie while I am breastfeeding? Is this ok?

    • Dr. Connie Sanchez, ND

      There are no known contraindication for consumiing ground flaxseeds in pregnancy and lactation – so go ahead and enjoy 1-2 TBS of ground flax seed in your green smoothies!

      • Dr. Connie Sanchez, ND

        There may be a contraindication during pregnancy; however, I did not find any contraindications for flaxseed consumption during lactation.

  • phiyl

    Hello, I’m wondering if I can “cook” a little bit the flaxseed before grinding them. This, because they taste better. I put a spoon in a hot pan for about 30 seconds. Not more. Just to roast them a little bit. Now, by doing that, do I arm the “good staff” of the seeds or it does not affect the seed itself. Thank You.

    • Wade Patton

      Flaxseed can be baked into breads at 350f without losing any nutritional benefits, per another video or article here. I light toasting isn’t going to hurt anything then by my guesstimation. As often said here, “The best way to eat plants is the way that you eat the most of them*”.

      *That assumes one is well-read enough to understand the problems inherent in cooking with oils, smoking, and charring/blackening.

    • Joshua Pritikin

      Flax oil has a very low smoke point (around 225F). Will the omega-3 get destroyed by toasting?

  • Dr. Greger,
    I LOVE my flaxseed! But I’m concerned because I’ve noticed some studies conclude that ALA has an incredibly poor conversion rate to EPA and DHA, basically meaning that a fishy source is best. I’ve also heard of sea algae is the superior plant-based source for DHA and EPA, but I’m unsure of its bioavailability…

    THANK YOU for all you do!!

    • Toxins

      The National Academy of Sciences does not recognize EPA and DHA as essential. This means there is enough evidence for them to conclude that we can make enough of it without eating it in its preformed state.

      “Interest in the cardiovascular protective effects of n–3 (omega-3) fatty acids has continued to evolve during the past 35 y since the original research describing the low cardiovascular event rate in Greenland Inuit was published by Dyerberg et al. Numerous in vitro experiments have shown that n–3 fatty acids may confer this benefit by several mechanisms: they are antiinflammatory, antithrombotic, and antiarrhythmic. The n–3 fatty acids that have received the most attention are those that are derived from a fish source; namely the longer-chain n–3 fatty acids eicosapentaenoic acid (EPA; 20:5n–3) and docosahexaenoic acid (DHA; 22:6n–3). More limited data are available on the cardiovascular effects of n–3 fatty acids derived from plants such as a-linolenic acid (ALA; 18:3n–3). Observational data suggest that diets rich in EPA, DHA, or ALA do reduce cardiovascular events, including myocardial infarction and sudden cardiac death; however, randomized controlled trial data are somewhat less clear. Several recent meta-analyses have suggested that dietary supplementation with EPA and DHA does not provide additive cardiovascular protection beyond standard care, but the heterogeneity of included studies may reduce the validity of their conclusions. No data exist on the potential therapeutic benefit of EPA, DHA, or ALA supplementation on those individuals who already consume a vegetarian diet. Overall, there is insufficient evidence to recommend n–3 fatty acid supplementation for the purposes of cardiovascular protection; however, ongoing studies such as the Alpha Omega Trial may provide further information.

      Combined with the lack of convincing clinical data in favor of n–3 fatty acid supplementation for cardiovascular endpoints and the lack of data in those that consume a vegetarian diet, it is difficult to make the recommendation that vegetarians should consume fish to optimize their cardiovascular mortality.”

      “Comparison of the PLLC n23 PUFAs:DALA ratio between dietary-habit groups showed that it was 209% higher in vegan men and 184% higher in vegan women than in fish-eaters, was 14% higher in vegetarian men and 6% higher in vegetarian women than in fish-eaters, and was 17% and 18% higher in male and female meat-eaters, respectively, than in fish-eaters This suggests that the statistically estimated conversion may be higher in non-fish-eaters than in fish-eaters.”

      In addition, another study showed that despise this “theoretical” low conversion rate, there is no evidence of any harm so, the problem may not be in the conversion rate, but in the assumption that it is low.

      “There is no evidence of adverse effects on health or cognitive function with lower DHA intake in vegetarians”

      “In the absence of convincing evidence for the deleterious effects resulting from the lack of DHA from the diet of vegetarians, it must be concluded that needs for omega-3 fatty acids can be met by dietary ALA. ”

      Eat your fruits and vegetables, add some flax or walnuts if you wish and you will be fine.

  • Tom Zdrojewski

    Would soaking flax seeds make them more digestible without grinding? I’ve been drinking lemonade and limeade with chia seeds and I was wondering if I could use flax seeds instead and still get the flax benefits without grinding them.

  • dnervina

    Just saw an article on WEB MD stating that if you have prostate cancer not to have Flax seed oil Because it make the cancer grow faster. Have you heard anything like this?

  • Dan Winkler

    Transcript says “heeling” but should be “healing.”

  • John

    I am a 68 year old male with an enlarged prostate but no cancer. I am very active (walk 5 miles a day, I run 15 miles a week, I XC Ski and bike) and I am 2 years vegan. I tried taking Saw Palmetto berry with no help. I am now on a generic version of Flow Max and that is not working either. I have been taking flaxseed but only a teaspoon a day with my cereal. My Doctor is recommending a TURP procedure and I am ready to try it. However, since I say this article, I am wondering if I should increase my flaxseed to 3 tablespoons per day and see if that helps. What do you suggest?

    • Arjan den Hollander.

      Try 20 grams a day, and I suggest you try the Swank diet for a few weeks and re-check the severity of your condition.
      I’ve seen a pretty dramatic improvement in micro circulation because of it and that seems to stimulate tissue behaving badly dramatically.
      Worth a try before going under the knife.

    • Wade Patton

      Saw Palmetto worked for me, but did nothing else that I’m aware. Using flaxseed has proven to be just as effective and comes with a host of other benefits and even tastes good. I would try increasing the daily dose one tsp at a time to get to 3 tbsp BEFORE I’d entertain any sort of medical procedure.

    • Brux

      May I ask you what are the symptoms of an enlarged prostate and why does one need to do anything about it if there is no cancer? This video talks about 2 tablespoons a day of flax, why not try that or more as WP suggests?

  • pentiger

    Hello Doctor. Per your advice I was using flax seeds daily with my morning banana/kale smoothie for about a month. I know all the benefits of this plant, however I don’t think I can consume it anymore since I started getting big acne outbreaks on my forehead and my back. To test my theory I stopped using for 7 days and acne almost completely disappeared. So I started adding it again and after just one day I got new zits on my forehead, now three days into I have a big outbreak. I have to mention that am a male and I follow complete vegan diet, of starches, other vegetables and fruit. Is there a way to get the benefits of the flax without breakouts on my skin, or maybe my body will adjust in time? Thanks in advance for any advice.

  • Haydus

    Thanks for all the dietary information you’ve given us, I’ve been following your videos and posts for quite some time and try to change my diet accordingly.
    I’ve recently started to add a daily dose of two tablespoons of ground flax seeds to my morning meal, mainly due to the omega 3 benefits (since I was afraid I’m not getting enough of it) and i came across several postings talking about the phytoestrogen found mainly in flax, but also in soy, sesame, chickpea, and other super foods regarded as healthy. Those posts talked about how the phytoestrogen found in those foods may function as estrogen in our body and may not be so good for men. As one of the conclusions there was that higher estrogen causes lower testosterone which is bad for sexual drive and fertility in men.
    Can you shed some light on this and, as always, help us to filter between true and false?

  • Brux

    It was said that flax seeds are a great natural source of zinc. That is great to know, but what I wonder about is where and how flax is grown? If flax takes the zinc out of the ground where it is grown, how do we know that the flax we buy is not grown in ground that is zinc deficient? After a few cycles, does anything put zinc back into the ground? This is my general question about plant foods from farms of all sorts. There are these mico-nutrients or minerals like zinc, or maybe iodine … and how do we really we are getting enough or any at all?

  • baggman744

    Is the doc saying buying ground flax is as good as grinding whole seeds fresh?

  • vegan minstrel is a fun song in agreement with Dr. G’s views on flax.

  • Stu Berkowitz

    Dr. Greger/Mr. Gonzales, does flax meal become toxic when it is baked? I’ve seen some posts and articles stating this online (and, as you know, everything you read on the Internet is true! ). Please advise. Thanks!

    • Shaylen Snarski

      Actually flax does really well when baked! The omega-3 content remains the same or almost the same… basically, you’re still getting lots of omega-3s. BUT this is from whole flax (flax meal, you have to crack the shells by grinding or they’ll just pass through you) NOT flax oil which you cannot heat! Also flax oil is very prone to rancidity, it’s highly sensitive. Whole flax is very stable. You should search for some of Dr. Greger’s other flax videos (can’t think of them specifically, but I know I’ve seen him talk about them elsewhere). I think with the baking, the temperatures were at 350 degrees F where the omega-3 content was shown to remain in tact. It’s certainly safe and healthy to cook with whole flax and you’ll get benefits, but just never cook with flax oil.

  • Will Fagg Rn

    I am excited about exploring the health benefits of flax seed, and brazil nuts as I try to lower my cholesterol without statins. I am prediabetic and statins increase your chance of getting diabetes, plus have a whole host of other side effects that might suck. I found uncle sams whole wheat berry and flaxseed cereal, but the flaxseed is whole, and it appears that you need to eat freshly ground flax seed to get all the health benefits. The front of the box mentions that there is omega 3 fatty acids from the flax seed. Is it bogus for the cereal to include whole flax seed, and boast of the nutrition value, when your body can’t absorb the nutrients unless the flax seed is ground up ?

  • prabha

    Is it good for a cancer patient to take good quality flaxseed oil everyday, as in Bugwig diet. What are your views about its rancidity?

    Thanks for the great infoon on this website.

    • Joseph Gonzales R.D.

      I think it’s a good idea to take flax daily for more than just cancer prevention, based on the data available. Dr. G hits on rancidity just go to topics and search the flax videos I guaruntee you’ll find what you are looking for. If not get back to me here. Thanks!

  • Littlel

    Does buying ready ground flax seeds reduce their antioxidant and/or vitamin and mineral content compared to buying them whole? i know this is true for vegetables and fruit i.e. if you buy ready sliced vegetables they are not so nutrient rich. Which is best to buy ground or whole?

    • Joseph Gonzales R.D.

      Hi Littlel. Thanks so much for your patience. Let me see…I think it’s best to buy them whole and then grind yourself. That way there is less risk the flax becomes oxidized. After ground they seems to only last a few months, as Dr. Greger describes.

      • Gumsvibe

        Hi Joseph,

        Would you say the same about Hemp Seeds vs Hemp powder?

        Thanks for all your helpful advice.

        • Joseph Gonzales R.D.

          Hemp is different don’t have to work so hard to get the benefits. I’d still keep them in fridge or freezer to preserve like with flax.

  • Jin
    • Shaylen Snarski

      There are some of the most insanely ridiculous blogs out there… you definitely have to be careful. I’ve never heard anything like that. Hopefully one of the volunteers here will comment to ease your mind. But honestly, I would not worry about this at all. Not to be “conspiracy theorist” or anything, but it is true that the animal agriculture industry has been putting a lot of false information out there about plant foods, especially the one’s becoming really popular, and even a staple, amongst vegans. The ag industry is suffering due to a growing vegan population, and while millions sadly still consume animals… multibillion dollar industries do NOT like to lose a single dime.

  • challett

    As it turns out, I am allergic to flax seeds & flax seed oil — I get hives. No one else I know is allergic to flax seeds. Even a few sprinkled across the top of a loaf of bread makes me break out/itch — I was wondering what would cause this.

    • Shaylen Snarski

      That sucks :( You should see how you do on hemp seeds. They have the perfect omega 6-3 ratio (flaxseeds have a TON of omega-3 even compared to omega-6, this is cool for the western world especially because due to all our processed foods we regularly eat, we have too much omega-6 compared to 3). Due to the ratio in hemp, you’ll get good omega-3 because our bodies actually prefer omega-3 and it beats out 6, but not when we overwhelm ourselves with excessive omega-6 (all learned from Dr. Greger and his appearance on BiteSized Vegan on youtube… which is how I found Dr. Greger).
      Anyways, hemp is cool because it also has SLA (hope I’m getting that right) which helps convert the ALA (short chain omega-3’s) into DHA and EPA.
      If you’re concerned about omega-3’s, you could take a direct DHA supplement from algae which is how some fish contain it in the first place: from eating algae. I like OmegaZen pure DHA as it has pure ingredients and is simply concentrated algae with no unhealthy and unsustainable binders or fillers.
      I do NOT recommend eating fish or taking fish oil as our oceans are dying from these things… there’s just no such thing as sustainable fishing anymore and it’s so bad that the government uses our taxes to massacre dolphins and seals and other endangered marine life, for eating the fish they’re meant to, instead of stopping the reason fish are so depleted in the first place, commercial fishing. So it not only perpetuates the problem but makes it a million times worse and is absolutely deplorable and certainly a waste of tax dollars, to say the absolute least.
      I also recommend using algae over fish oil or eating fish, for direct DHA, for health reasons. You don’t get all the very dangerous contaminants such as heavy metals and radiation, etc.
      And of course, fish have a nervous system and feel pain. And there is always a “by-catch” where sea turtles, dolphins, and other marine life is incidentally caught and killed during fishing.

      Oh and you don’t need to worry about getting EPA in the supplement, your body converts this from DHA and even ALA.

  • Joshua Pritikin

    Ground flax takes up a lot more space than flax seed. When I measure out 1 tablespoon of flax, I measure the ground flax or the whole flax seed?

  • CarlF

    Do TOASTED flax seeds have less benefit the raw?

    • Shaylen Snarski

      Flax actually does really well when baked as far as the omega-3 content goes. So you still get benefits from cooked flax. I’m sure some nutrients are lost during cooking though.

  • Shaylen Snarski

    I’ve been putting 1/4th cup organic ground flax in my smoothies everyday for a little while, then I read this on “Cyanide” is a term that we typically associate with the potentially deadly poison, hydrogen cyanide. However, there are very small amounts of cyanide constantly present and undergoing metabolism in human tissue. These small amounts of cyanide are found in relatively non-toxic forms like thiocyanates. Of course, these same thiocyanates are also found to occur naturally in foods (for example, in cruciferous vegetables). Linamarin and lotaustralin are two of the primary cyanogenic glycosides in flaxseeds, and like the thiocyanates in cruciferous vegetables, both of these compounds can contribute to cyanide metabolism in humans. However, as long as our metabolic processes are not overloaded and we are in reasonably good health, about two tablespoons of flaxseeds per day are likely to provide too little linamarin and lotaustralin to cause an adverse reaction. We’ve seen research on flaxseed meal, for example, which shows about 5-6 milligrams of cyanogenic glycosides (CGs) in one tablespoon. (And to give you a comparison, oral doses of sodium cyanide and potassium cyanide that cause acute and dangerous toxicity in humans fall into the range of 1000’s of milligrams.)”
    Now I’m all paranoid, so annoying… So is 1/4th cup too much? Should we only have 2 tablespoons? Based on another video I’ve seen by Dr. Greger, plants have a way of regulating any negative things in them with their own abundant antioxidants, fiber, and other nutrients… so I’m doubting I have to worry but I just wanted see what Dr. Greger or anyone else who can help, has to say.
    My instincts tell me to trust in organic whole plant foods and not to worry.

    Thanks! You can see the full article here:

    • David Sprouse MS PA-C NF Mod

      Hi Shaylen,
      Although I don’t claim to be an expert in this particular area (cyanogenic glycosides in whole foods), I agree with your instincts not to worry, especially since these compounds are found in such relatively small amounts and are also in other whole foods such as cruciferous vegetables.

  • Laura

    I read the article about hot flashes, and it said they used 40grams per day in the trial. How much is this in tablespoons? What is your recommended dosage for hot flash reduction?

    • David Sprouse MS PA-C NF Mod

      Hi Laura,
      My ground flax seeds (Spectrum brand) have 14 grams in 2 level tablespoons.

  • I currently am taking in too much fiber, and so while I have been using ground flax seed in my smoothies, I’m switching to oil. Am I really losing that much of the health benefits? I’m getting plenty of fiber and other nutrients in my diet so I wasn’t all that worried, but is it worth it to just do flax oil?

  • kathy

    How hot can ground flax seed be without rancidity? I understand that your cold grinding is
    essential but if typical grinding makes the flax too hot, what cooking temp is

  • Melissa Miller

    I developed endometrial carcinoma at age 33. I have had a total hysterectomy, oophorectomy, and radiation (which caused damage to other organs!). I was not allowed to take any hormones. I switched to a plant based diet and would like to consume flax seeds. Will eating flax seeds be harmful for me? Thank you for your outstanding work, Dr. Greger.

  • Martin

    If I make my own bread, and I add the daily dose of flax seeds wheet to it, will the good nutrients in flax be destroyed by cooking the bread in the oven ?

  • Hayley Rabbitts

    Hello… How high are ground Flax in Omega 3’s?? Is this the best source if I am vegetarian and pregnant? I bought the oil, (UDOS’S) but think i will switch to grounding them up in my smoothies instead. Thank you for your help…

    • David Sprouse MS PA-C NF Mod

      Hi Hayley,
      2.9 grams of omega-3 (ALA) in 2 tablespoons. I buy the pre-ground (vacuum sealed) packages made by Spectrum Naturals and store them in the freezer to add to my smoothies. No pre-grinding necessary! :)

  • Fianne

    Last week I discoverd your site and I can’t stop watching a lot of your video’s! So much new things to learn :-) Love it :-)
    You talk a lot about flax seeds, but what do you know about the health promoting proporties of hemp seeds? Are there any studies done with hemp seeds?
    I love to sprinkle them over a slice of bread bread with peanut butter, since I heard that it was very healthy. But how healthy is it?

  • Johan Brundin

    First of all I would like to thank you for your wonderful site and youtube channel.
    To the question: Here in Sweden out national department of health have issued a recommendation to not eat ground flax seeds due to the risk to raise the level of hydrogen cyanide in the body, also they even recommend that food stores should not even sell it.
    When searching the internet I cannot find anything outside Sweden that talks about cyanide and flax seeds, do you know anything about this?
    Here is the link although in swedish to the article:
    It seem like they mean that they cannot guarantee what dose is safe to eat.

    • Sara Dunard Reuter

      Hi Johan!

      I’m also researching this and have gotten the same impression as you. I’m really interested in hearing Dr. Gregers take on this, and was thinking of submitting a question.

    • Thea

      Johan Brundin: Your question has come up a lot lately. I think the following answer from Tuffs is helpful in evaluating this question:
      “Lynne M. Ausman, DSc, RD, director of the Biochemical and Molecular Nutrition Program at Tufts’ HNRCA Cardiovascular Nutrition Laboratory, says you have nothing to worry about. Many foods, including not only flax but cashews, almonds, some beans and other plant products, naturally contain very small amounts of cyanide compounds. You’re more likely to ingest these trace amounts of cyanide when such foods are consumed raw, as heat breaks down the compounds. Even when flaxseed is eaten raw, the body has a natural capacity to break down a certain amount of these cyanide compounds. A 1994 study found that, in healthy individuals, daily consumption of as much as 60 grams of raw flaxseed—more than eight tablespoons—was safe” from:
      Since Dr. Greger recommends only 1 tablespoon of ground flaxseed in his Daily Dozen recommendaitons, it seems to me that it is all good – a large safety margin *and* a huge amount of potential benefit from the flax.
      For the gritty details, check out: ​
      FYI: I heard that Dr. Greger will be doing a video on this topic at some point, so stay tuned!

      • Johan Brundin

        >Thank you for your answer Thea!
        That is at least a little calming :) although the 60 grams of flax seed seem to be hole seeds that (at least as I understands it) passes pretty much right through the body it may not say so much about the risk of ground seeds?
        I will be looking forward to the video!

  • GreenClaudi

    Hello from Germany, I thanks for the videos. I have read Boron is very good for Hyperparathyreoids, it make the adenom smaller. Since 7 month I am vegan. Since this time is my Parathyroid Hormone level from before 150 to 379. And I don´t know why, maby I eat to few protein (sometimes I eat only 25 – 35 g per day) or maby it because now more alkaline (7,5 and 8) in mornig few. I was by a vegan Dr. but she don´t know about it and normal Doctor say it again meat. But know I don´t like eat again meat. Sorry for my bad english, i hope u understand.

    Because I found not information about primary hyperparathyroidism, it would be woundelful u can make a video clip about this and vegan.

    Thank you for this good information side. I have buy the wounderful book “How not to die”, but it is only in englisch, not really all understand, I hope one day come it in german.



  • Bat Marty

    I have a question: my raw food facebook group discourages eating fat and sweet food at the same time saying that the fat (in this case it could be flaxseeds) messes up the metabolism of the sweet foods, and provokes a higher insulin response because the sugar of fruit for example cannot get to the cells and remains in the bloodstream longer –> more insulin. Is that true?