Omega-3 Fatty Acids Linked to Higher Risk of Cancer?

[williswine]

Just saw this on time.com: http://healthland.time.com/2013/07/11/h ... of-cancer/ (hope it's ok to post a link).

I wonder what our nutritional experts think of this article...

[Reub]

http://www.nutraingredients.com/Researc ... eRnA%3D%3D

"Experts slam omega-3 link to prostate cancer as overblown 'scaremongering'."

[Kriegsspiel]

Everything causes cancer.

[l82start]

http://www.michaelsavage.wnd.com/wp-inc ... ERVIEW.mp3 a nutritionist and a former nutritionist turned talk-show host (Michale savage) discus the quality of the science in the omega 3 cancer connection study

[Gumby]

Just saw this on time.com: http://healthland.time.com/2013/07/11/h ... of-cancer/ (hope it's ok to post a link).

I wonder what our nutritional experts think of this article...

I already mentioned this in another thread. Omega-3 is a Polyunsaturated Fatty Acids (PUFA), and PUFAs in general are highly unstable — that's why high quality PUFA oils (Fish Oil, Flax Oil) are kept refrigerated. They tend to oxidize and react very easily. And putting large quantities of these oils into a 98º body and a highly acid stomach is a recipe for increased oxidative stress over the long term.

So, if you're trying to optimize your Omega-3/6 ratio, it's far better to reduce Omega-6 than it is to increase Omega-3. In fact, the dietary need for Omega-3 for all other mammals is actually pretty miniscule. Humans perhaps need a bit more DHA for their larger brains, but there isn't very good evidence that humans need a LOT of DHA/EPA (the Omega-3 longer chain fatty acids).

Fish Oil companies have sponsored a lot studies that show therapeutic benefit for high quantities of (Omega-3) Fish Oil consumption over the short term. But, there haven't been many studies for long term Fish Oil consumption. And some of the longer term studies for Fish Oil consumption show higher mortality for those Fish Oil.

See: http://chriskresser.com/when-it-comes-t ... not-better

And... http://perfecthealthdiet.com/2010/06/fi ... -capsules/

So, based on what I've seen, I would avoid Fish Oils and just eat up to a (but not more than) a pound per week of fatty fish. If you do that and minimize Omega-6 consumption (avoid industrial seed and vegetable oils), you should be fine in that regard.

In general, Fish Oil should only be used (sparingly) by people who don't eat fish.

Interestingly, it's believed that early humans obtained DHA by eating the brains of the animals they killed. Apparently the leg bones and heads were often prioritized — often quickly removed from carcasses and carried back to their camps!

[moda0306]

Gumby,

Isn't the best way of reducing omega 6 intake eating less meat?  This seems to be contradiction.

[Gumby]

Gumby,

Isn't the best way of reducing omega 6 intake eating less meat?  This seems to be contradiction.

Eating less grain fed meat, yes.  But, the grass fed/pastured meats have an excellent Omega-3/Omega-6 ratio. Here's a great chart that compares the Omega-3/Omega-6 ratio of grain fed vs. grass fed meats (see last column):

http://www.ncbi.nlm.nih.gov/pmc/article ... /table/T2/

It's really stunning how much Omega 6 is in grain fed meats. But, grass-fed meats are almost perfectly balanced!

But, to answer your question, the best way to minimize Omega-6 exposure is to eat less Omega-6-rich foods. Omega-6 is found in anything derived from grains and seeds (i.e. grain-fed meats, industrial seed oils, grains in general). I don't want to get into a whole discussion about grains again, but that's where large quantities of Omega-6 really comes from. As you could probably guess, humans weren't really able to obtain huge quantities of Omega-6 before the agricultural revolution — so high Omega-6 consumption is relatively new in the human diet.

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Coconut Oil is one of the few plant-based fats that is low in Omega-6 — since it's entirely composed of saturated fat. Saturated fat, by definition, is not PUFA, so therefore it has barely any of the "Omegas". And that's a good thing when you are cooking since PUFAs are so reactive (and should be only used cold). Saturated fats resist heat and oxidation better due to their strong molecular structure (which PUFAs lack). You could also cook with a saturated fat from a pastured animal (which would also be low in PUFA) such as grass-fed butter. But, I believe coconut oil is cheaper and easier for most people to obtain.

[williswine]

Great supplemental info so far!  Good thing I rely on eating the real thing (though mostly canned) rather than fish oil pills. As always with everything nutritional, it is more complex than it seems. For example, the first link provided by Gumby discusses the benefits of continuing to consume fermented cod liver oil but not other fish oils.

Thank you Gumby for reminding to consider coconut oil when cooking. Need to also look into using this.

[Reub]

http://www.drhoffman.com/page.cfm/1213

"In fact, every scientific principle to date points to the efficacy of omega 3 fatty acids in preventing prostate cancer. They are anti-inflammatory, and chronic inflammation is thought to be at the root of many common cancers, including prostate cancer. They help to regulate insulin, a powerful driver of many cancers by virtue of its potentiation of insulin-like growth factor (IGF-1). They may even help regulate cell replication, preventing run-away proliferation and metastases that occur in cancer. They help to prevent cancer cachexia, a wasting condition in patients with advanced cancer."

[Gumby]

http://www.drhoffman.com/page.cfm/1213

"In fact, every scientific principle to date points to the efficacy of omega 3 fatty acids in preventing prostate cancer. They are anti-inflammatory, and chronic inflammation is thought to be at the root of many common cancers, including prostate cancer. They help to regulate insulin, a powerful driver of many cancers by virtue of its potentiation of insulin-like growth factor (IGF-1). They may even help regulate cell replication, preventing run-away proliferation and metastases that occur in cancer. They help to prevent cancer cachexia, a wasting condition in patients with advanced cancer."

He's not wrong. Omega-3s are certainly good for you. No one would argue against that. However, he is wrong when he says...

Biologically, there's no plausible reason to suspect that too much omega 3 could be cancer-causing.

...because there certainly is a proposed possible mechanism.

Angiogenesis is the creation of new blood vessels in mature tissue and it is a normal part of wound healing. However, inappropriate angiogenesis contributes to a number of diseases, such as tumors. DHA appears to have pro-angiogenic effects that may promote cancer when taken in excess. Paul Jaminet wrote about that mechanism in 2011 (after the first study linking DHA to cancer was published by the same authors):

http://perfecthealthdiet.com/2011/04/om ... r-part-ii/

But, the criticisms on the study are valid in that correlation does not equal causation. The fact of the matter is, despite the potentially flawed studies, we can't rule out that excess Omega-3s may indeed be harmful.

A good way to sum all this up is this:

Even though this study doesn’t give any reason to shun fatty fish or their oils, it’s a nice segue into a related issue: A bad diet plus fish oil is still a bad diet. And given the oxidation-prone nature of all polyunsaturated fats, a massive intake of omega-3’s – despite their brilliance in moderation – could potentially do more harm than good. If you’re trying to restore a healthy ratio of omega fats, avoiding omega-6-rich foods (and supplementing wisely) is a better strategy than chugging fish oil like a frat boy with gin.

Source: http://www.marksdailyapple.com/fish-oil ... te-cancer/

[Benko]

1. I would not trust Michael Savage's opinion on nutritional matters.

2.  too much omega 3's supress your immune system (acutely--I stop taking fish oil caps when I'm ill) and there was similar data on flaxseed being linked to prostate cancer.  OTOH if you have high triglycerides, or RHEUMATOID arthritis, or other inflammatory conditions, taking high levels of omage threes long term might be a good idea.

DIET AND SUPPLEMENTS NEED TO BE INDIVIDUALIZED as people are different with different genetics, health issues, age, etc.

3. "And given the oxidation-prone nature of all polyunsaturated fats, a massive intake of omega-3’s – despite their brilliance in moderation – could potentially do more harm than good"

The words "massive" and "moderate" are certainly in the eyes of the beholder i.e. what is massive and what is moderate?  Plus perhaps higher doses of fish oil merit high doses of APPROPRIATE antioxidants.

4.  DHA is critical to infant brain development i.e. pregnant women would do well to supplement it.  DHA tends to be lower in older people. Whether this is nature's way of preventing problems (which just occured to me) or whether it is something that should be remedied I don't know.

5. From previous discussions, beef has better omega 3/6 ratio that other meats e.g. chicken.

[notsheigetz]

I've been in the habit of ignoring headlines that say something has been "linked" to cancer or some other disease.

Having said that I think I did prove to my own satisfaction that my use of krill oil was causing excessively blood thinning in the form of purpura's on my forearms. They ceased shortly after I stopped taking it.

[l82start]

1. I would not trust Michael Savage's opinion on nutritional matters.

nor would i necessarily......  but  the way study's are done and what qualifies as good science vs sloppy science hasn't changed since he got a degree in the subject,  i don't recognize the name of the other nutritionist he is interviewing maybe he is not a great source either, but the questions they raise sound legitimate enough to warrant some skepticism of the study...

nutrition is a topic highly prone to dramatic presentation in media headlines, i suspect nutritionists are far more likely to make carefully couched statements over bold black and white proclamations..

[Gumby]

1. I would not trust Michael Savage's opinion on nutritional matters.

nor would i necessarily......  but  the way study's are done and what qualifies as good science vs sloppy science hasn't changed since he got a degree in the subject,  i don't recognize the name of the other nutritionist he is interviewing maybe he is not a great source either, but the questions they raise sound legitimate enough to warrant some skepticism of the study...

nutrition is a topic highly prone to dramatic presentation in media headlines, i suspect nutritionists are far more likely to make carefully couched statements over bold black and white proclamations..

True, but it's worth noting that Michael Savage didn't interview anyone who thought that there might be a plausible explanation for excess DHA causing prostate cancer. I mean, Paracelsus's rule: “the dose makes the poison”? can apply to anything — even every day nutrients. And yet, it sounds like he just wanted to interview the first person he could find to debunk the study so that he could feel better about taking fish oil. Well, it's not difficult to debunk a study. That doesn't make the hypothesis right or wrong. It's still just a hypothesis that's worth discussing and testing further.

And in a bit of irony, the two lamented about how these observational studies are never able to prove anything (which, again, is true) and then in the very next breath his guest says that the higher intake of soy in the Japanese diet somehow proves that soy reduces prostate cancer. Well, that too is correlation not equalling causation. And never mind that the Japanese traditionally ate fermented soy,  which removes a lot of soy toxins, while Americans tends to prefer their soy raw, with all the toxins still intact.

Anyway, you are correct that it's not a good idea to take health advice from the media, since all the media does is read the headlines and never parses the data. My guess is that 'the dose makes the poison' applies to any nutrient — even DHA or even water.

[l82start]

And in a bit of irony, the two lamented about how these observational studies are never able to prove anything (which, again, is true) and then in the very next breath his guest says that the higher intake of soy in the Japanese diet somehow proves that soy reduces prostate cancer. Well, that too is correlation not equalling causation. And never mind that the Japanese traditionally ate fermented soy,  which removes a lot of soy toxins, while Americans tends to prefer their soy raw, with all the toxins still intact.

Anyway, you are correct that it's not a good idea to take health advice from the media, since all the media does is read the headlines and never parses the data. My guess is that 'the dose makes the poison' applies to any nutrient — even DHA or even water.

good catch ... i didn't spot that one
i agree that there could be a DHA cancer relationship as you said "the dose makes the poison."

as a side note i am taking a nutrition class at a local city college right now, i bet this topic gets talked about in class, if the professor has anything interesting to say i will report back...