Dear Mark: Is Flax Bad?
Dear Mark,
I’ve been researching flax and am ready to pull the plug on my dedicated flaxseed grinder. The kicker was seeing flaxseeds associated with prostate cancer. What’s your take?
Thanks to reader Clare for the thoughtful correspondence on flax. This is exactly why I love doing this blog. Research continues to unfold, and the conversation never fails to engage and inspire me.
As Apples know, I’ve been a flax supporter. Lately, I’ve been mulling that position. While I don’t think a single study’s results should rewrite the book on any issue, when a number of studies suggest that it may be linked to serious illness in some people, that’s enough to give me pause. And, well, it’s enough to incite me to do some digging – and pondering. Flax is one of those cases lately.
The deal is this. Flax seed is rich in a form of omega-3 fatty acids called ALA (alpha-linolenic acid). Omega-3 fatty acids as a whole (group) are especially vital for the development and ongoing well-being of the nervous system and for the health of the cardiovascular system. They improve lipid profiles, thin blood, and combat inflammation like nobody’s business. (You know how I feel about that one, eh?) They can also help curb insulin resistance.
Research time and again supports the role of omega-3s (again, as a group) in overall health; however, some studies and reviews over the last few years have linked high ALA intake (from both flax oil and milled seed) with higher incidence of prostate cancer. ALA blood levels are higher in response to flax oil intake than they are with milled seed intake. (Eating whole seeds isn’t recommended unless you’re looking for some serious abdominal havoc.)
I’ve always maintained that other animal-based forms of DHA and EPA offer more health-related bang for your buck, and I stand by that point. The preponderance of research supports the particular power of EPA and DHA in the omega-3 fatty acids. One study suggests that fish intake (rich in both DHA and EPA) actually reduces the risk for prostate cancer.
The bottom line is ALA doesn’t do much that DHA and/or EPA can’t do and probably do better. As avid Apples know, I suggest that everyone take a fish supplement. In the past I’ve seen ALA as a decent secondary choice for vegetarians and as a useful addition to a healthy Primal eating strategy (e.g. a bit of ground flax seed on some berries). The human body isn’t terribly effective at converting ALA to either DHA or EPA, hence the need for added dietary intake or supplementation. (An interesting side nugget: women’s bodies are a little better at this conversion. Research has shown that young women convert 21% of ALA to EPA (compared to 8% in men) and 9% to DHA (compared to 0-4% in men). The difference, apparently, is linked to estrogen levels.)
So, what’s my current suggestion in light of the potential prostate cancer link? If you’re a woman, the obvious point of the research isn’t relevant. Nonetheless, the underlying role of phytoestrogens in flax is nonetheless an important one. I’d say that healthy women can consume low to moderate amounts of flax without concern. Sure, a large amount of research suggests the protective effect of phytoestrogens against breast cancer (in healthy women), and this research includes flax. Nonetheless, a lot of a seemingly good thing isn’t necessarily better or even safe. My advice would be to use fish oil as your primary omega-3 source and keep the ALA on the lower side.
If you’re a man? Particularly an older man? I’d definitely suggest you make fish oil your principal source of omega-3s. Is it time to chuck the flax grinder all together? Based on the research, I’d at least put it into semi-retirement. (I’d suggest forgoing flax oil entirely.) In the meantime, we’ll stay on top of this one and let you know about any new developments on this front.
As always, thanks for your questions and comments. Keep ‘em coming!
diglyesica, tellumo, spdrecrd Flickr Photos (CC)
Further Reading:
Omega 3 Fatty Acids Round Up:
Modern Forager: The Vaunted Flax Seed
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Posted By: Mark Sisson
This post is somewhat refreshing to me. I have never really been a fan of adding Flax to my diet. Not because I thought it bad for you but more because I have never enjoyed it and have always had difficult fitting it in time, place and taste wise with my diet. I still make sure i get plenty of omega-3′s though! Flax was looked at as almost a mecca back in my bodybuilding days but if more research shows this to be bad thing then I will be glad yet again that I ignored the mainstream hype.
The issue of flax is very complicated. I don’t see anything on the web that would preclude adding flax in moderate amounts to the diet.
nannyflute
I think flax is great but it must be used in the right way, the fact that when consumed as seeds (unground) they are a potent Estrogen metabolizes is something very interesting for men…I regularly add the seeds to yoghurt and shakes or even sprinkle some in burgers……I think its also best to mill your own batches of Flax and keep them in the fridge to ensure optimal freshness….
Just so I understand correctly..flax seeds can help men lower estrogen levels? (And thus reduce the effects of it?)
Or did I get this backwards?
Mark – thanks for this info. I have a couple of questions.
1. I have about 1000mg of flax seed oil per day – is this a relatively low amount in the context of this discussion? All this talk of flax grinders makes me think my consumption is probably on the low side, but it would be good to get your view.
2. I do get a lot of fish oil in my diet both via food and supplementation but had always understood that ALA offers something extra that is needed to complete the omega 3 picture. If this is not true I’ll happily ditch the flax oil and stick to the fish oil – one less bottle on the shelf!
Thanks.
I’m not a fan of flax. Interesting, people with certain endocrine disorders can not tolerate flax, including myself. I’d stick with the fish oil or grass-fed meat.
i cant see anything past september 6th?
Thank you for the comment, Anna. We are working on a solution. I apologize for the inconvenience. In the meantime, Firefox seems to be displaying MDA just fine.
As we age, the enzyme (delta-6 desaturase) that converts Omega-3 to EPA/DHA, decreases in activity.
Thus with less anti-inflammatory EPA/DHA oils, the prostate, as well as other tissues, would become inflamed and dysfunctional.
I am willing to bet that with increased ALA in the diet, not only prostate cancer, but, other cancers would exist too.
How about the fibre content; is flax seed at least a valuable source of fibre? (Not that anyone following the PB diet needs to add fibre to the bountiful amount that veggies provide!)
I don’t understand why whole unground seeds pose a potential problem. Would not Grok have nibbled on a few pinches of flax seeds as he found them? Aren’t they whole, unprocessed, natural goodness?
I don’t know if my smoothies will ever be as good without the flax.
Hi Mark,
Can you let me know your thoughts on omega 3′s post workout? I had read somewhere that this is not optimal.
Thanks,
Crystal,you said that people with certain endocrine problems cannot handle flax. Is that someone who is hypothyroid?
There’s an inaccuracy in this article – there are vegan EPA and DHA supplements from algae.
http://www.water4.net/
Possibly Sue. There isn’t a lot of info. out there but it is common among hypoT./hypoA. people. It must have something to do with the conversion causing stress. Others think it’s a goitergen and should not be eaten.
Some people are intolerant to flax worsening a nervous/emotional disorder—but what is described is actually low cortisol IMO.
Hello Mark,
Any opinion on chia seeds as an omega source, flax alternative?
Thanks!
I use a high-quality liquid fish oil as my main supplement to combat inflammation and have really cut back on the flaxseeds (ground) after talking with my natural doctor. He suggested trying hemp seeds.
I would also be interested in similar research (if it exists) on both chia and hemp seeds.
Tony – The article doesn’t say there aren’t vegan sources; only that ALA is an option for vegetarians.
Thanks for the link.
DC – Thanks for the question. I think we have a chia seeds post in the works. Check back!
Aaron, thanks for your response. Actually, Mark does say that there aren’t any vegan options for DHA and EPA:
“I’ve always maintained that other animal-based forms DHA and EPA offer more health-related bang for your buck, and I stand by that point.”
He says that DHA and EPA are “animal-based forms” of Omega-3s. This isn’t true and weakens his conclusion that fish oil is the best solution for those trying to get a healthy balance of Omega-3s.
Tony – I’m still not sure how you get that Mark is saying vegan sources of DHA and EPA don’t exist. He is simply saying that he has always said that it is better to get Omega 3s via animals than flax. At least this is how I read it. Nevertheless I am pretty sure this is what was meant…
Hey Aaron. In the passage I quoted above Mark specifically says that EPA and DHA are animal-based.
“He is simply saying that he has always said that it is better to get Omega 3s via animals than flax.”
No, he isn’t simply saying that fish oil is better than flax – what he’s saying is that he recommends fish oil as the best source of a good balance of omega 3s (out of all options, not just compared to flax). Without any mention of plant-based EPA and DHA this conclusion seems hasty at best.
I know people find it obnoxious when vegans go on about their diets, but the reason we’re prone to preach is because the diet is so frequently unfairly maligned. I think it’s obvious that any reader will come away from the above article thinking that eating animals (in some form) is the only way to optimal health. This is a damn shame because it’s just not true, and while I’m sure it’s not Mark’s intent to knock veganism, by completely ignoring vegan DHA and EPA and coming to an ill-informed conclusion, that’s the effect his article has.
Because someone might come along and read this later: I cannot go vegan unless I want to bleed out through my uterus. You can’t get real vitamin A from a vegan diet. I find that if I go low on vitamin A, my cycle gets all messed up. I am not the only one with this experience. A friend of mine on FB heard about my problem and tried vitamin A in her own health regimen and had the same results I did. And charity clinics in developing countries often use vitamin A to cure dysmenorrhea (sp?) in women of those countries. Not to mention it is vitamin A capsules, not golden rice, which are used to prevent blindness in children. (Kids under five can’t even convert beta carotene!)
You also can’t get B12 in a vegan diet. You MUST supplement. If you *have* to get a nutrient from a pill in order to follow the rules of your diet, by definition your diet is not healthy. There’s a difference between just missing out on a nutrient because you didn’t eat enough of a food allowed in your dietary pattern, and *having* to supplement because the nutrient isn’t in any allowed foods at all.
There isn’t anything unfair about maligning a diet that, followed properly, results in malnutrition. Vegans can only be vegans because you have an industrial support system that makes supplement pills for you. Follow it if you want. But we’re not the ones making inferior dietary decisions. It’s foolish to rely on machines for all of your intake of any nutrient, and even more foolish to cite farm animals not being fed species-appropriate diets as your excuse for not following a species-appropriate diet yourself.
The algae supplements come from Switzerland. Are they available in other countries?
I think its a lot easier to achieve optimal health on a diet that includes meat. It could possibly be achieved on a vegetarian diet but with a lot more thought and possibly a lot more supplements.
I stopped grinding flax a year or so ago based on the mixed research, some of it is pretty strong, same thing with soy, too much risk, there’s proof to suggest they are unsafe, that’s enough for me, other things like cod liver oil have down sides (pro oxidant, rancidity, heavy metals etc) but the research is more favourable, so i still consume it.
Hey Sue, I don’t really know of any other vegan DHA and EPA supplements, but I do remember reading about others in development a few years ago when V-Pure came out. Although they’re based in Switzerland I think they deliver to the states. Supposedly they’re also working on an algae-based b12 supplement, more good news for vegans.
“I think its a lot easier to achieve optimal health on a diet that includes meat.”
I think in general this is true – planning a vegan diet in our meat-obsessed culture can take some time. However, there are lots of health problems associated with meat that vegans don’t deal with at all. Aside from the correlation with heart disease etc (which can be avoided if you eat the right meats), I am mainly thinking of accumulated toxins. Of course, you can buy free-range, grass-fed, no-antibiotics etc etc, but this can be difficult and costly. I’m guess what I’m trying to say is that for truly optimal health (which includes no toxins) it might be easier to just go vegan (also wayyyyy cheaper). There aren’t even really many supplements – b12 is the only one you absolutely need and then the omega-3s.
Here is a thing from the V-Pure site, about “the dangers of fish oil.” Obviously, V-Pure has a business interest in convincing you of its claims, but then again, so do many proponents of fish oil.
http://www.water4.net/fish-oil.htm
Again, I’m not trying to preach but it’s just SO frustrating when every single bit of advertising and health advice you see is a paean to the wholly destructive industrial meat industry.
For a far more detailed rundown of EHA and DPA:
http://www.nutrispeak.com/omega_3s__epa___dha.htm
This may have been answered already but I can’t find it…I have never found a fish oil that doesn’t “repeat” on me. I have tried (& returned) virtually every one that anyone even suggested would agree with me. I even tried just a liquid which was mixed in with my daily protein smoothie. Yuck & ick! The only one even remotely palatable has been Coromega–but it seems pretty low dosage. Any suggestions? I currently take a 1000 mg “organic” flaxseed oil cap. daily. I’m 63 & take no medications.
I take Carlson’s Cod Liver Oil Professional Formula with light lemon flavour. I’m not saying it doesn’t ever “repeat” but I take it at night shortly before bed so it doesn’t bother me. I admit if I take it in the morning I can have an issue. Both of my 60 year-old parents take it in the morning, though, and never have a problem.
I wouldn’t mix any CLO with food, even a smoothie– the taste always comes through. It doesn’t taste wonderful, but with a sip of water I down it like a pill and it’s not too fishy (like some other CLO I’ve tried). I’m a huge baby about taking anything that tastes bad, so if I find it palatable, I think anyone could handle it. Good luck!
**OT, but can’t wait to read the chia post.
recently had a green bar w/chia..then started reading up on someone making chia drinks, etc. The fiber content is out of this world..
will check back soon.
Ground flax seeds do NOT cause any sort of cancer. This is another paranoid headline-grabbing phenomenon based on dubious science from a tiny study or handful of studies. Who sponsored the research? Think about it- who the heck would pay to study a link between flax seeds and prostate cancer? It wouldn’t surprise me if it was another scare tactic by the meat or pharmaceutical industry. Reminds me of the garbage about too much Vitamin E, too much soy, and most recently drinking too much water. There will always be research that supports or attacks anything ever studied. Intelligent people read a cross section, take note who sponsored which studies, and act in accordance with the majority of independent science. The majority of independent science in regard to flax seeds is clear: they are an extremely beneficial food. Period.
Peter, you said:
“Ground flax seeds do NOT cause any sort of cancer”
You can’t make such a statement, where is your proof that it doesn’t cause cancer. Flaxseeds contain phyto-oestrogens so it makes sense that there would be a study examining any links with cancer.
Susan-
In science, one doesn’t normally seek to prove that a substance DOESN’T cause something, (such as cancer); one normally attempts to prove that it DOES. The scary word “phyto-estrogens” literally means plant estrogens. Virtually every healthy food we eat — most vegetables, most fruits, grains, beans, nuts, seeds, and roots — all contain phytoestrogens. Perhaps you didn’t realize that. The preponderance of independent research in fact indicates that phytoestrogens actually PROTECTS tissues from the cancer-causing effects of xenoestrogens and other hormonal pollutants. I repeat my suspicion as to why flax seeds were singled out for such a misleading headline. What’s next- broccoli causes melanoma?
And I repeat: who sponsored that so-called “research”?
Anyone here know?
Mark?
Thank you. -P
How come there’s no info on who did the study and what they did in the study? We need the proof before we can believe that this is true. To me it sounds like someone just made this up, why only flax and what about the other foods that have ALA in them? If it was the ALA that caused prostate cancer then why is flax the only food to be targeted?
It’s always a relief to see a note of reason, in present case, from Peter and Michael. I spend a lot of time finding valid info for consumers, and have seen good double-blind clinical studies [not funded by special interests] which have shown that flaxseed consumption is definitely beneficial in opposing prostate and other cancers. Anyone who has a cause to prove can always find something to back it, of course. The amount of irresponsibility so often seen re: quoting an isolated study [which as Peter and Michael have pointed out was not even identified] is sad. It is doubly so when that’s done by someone who speaks as an authority. This is a position, which once chosen, demands objectivity and thoroughness due to influence on the uninformed. –Linda
The study is mentioned above. Just click on the link just after the picture of the flax bottle.