You Expect Me To Believe That?

fishoil-hookSome things just belong together. Not too many of us eat only the meringue from the lemon pie. Sauerkraut on a bun without the sausage isn’t quite the same gustatory delight. And sometimes the aunt is more fun when in the company of the uncle. Such is the case with essential fatty acids. The omega-3’s can do their job without the omega-6’s, but the outcome will eventually be out of whack. It’s this imbalance that wrought the nefarious genius of a twisted, fear-huckstering fish oil report, so carefully crafted that the typical reader comes to believe that black is white.

The study reported in the Journal of the National Cancer Institute determined a positive relationship of non-vegetable sourced omega-3 fatty acids to prostate cancer. If non-vegetable, that leaves fish oil, known better for its downstream n-3 fats, EPA and DHA, than for the mother n-3, alpha-linolenic acid. The concern with this proposition is that the authors seem to have gone from home plate to home plate, in a 360-foot path without ever touching any of the bases. Healthy incredulity befits the reading of a ‘scientific’ paper. That leaves questions that most of us don’t ponder, including these:  Why would anyone take n-3 fats without also taking n-6 complements? Did any of the subjects bear a pre-existing pathology? Were the supplements, if used, of sufficiently high quality, as you would expect from a cGMP-obligated company? (The term “pharmaceutical grade” means only that toxins have been removed, and is otherwise unregulated, since many products that call themselves fish oil are not oils but ethyl esters instead of triglycerides.) Is it possible that individuals were removed from the study because they got healthy all of a sudden? Not to be too picky, but what were the capsules themselves made from, if supplements are to blame? Could the supplements have been combined with active pharmaceuticals or with contraindicated other supplements? Not finally, but at least additionally, why is it so that countries whose cuisine is dominated by fish—Scandinavia or Japan—do not also present a high level of prostate cancer? Funny thing:  this study failed to tell us where the men in this investigation got their omega-3 fats. The dollar store? Canned tuna? Maybe from the fish they ate an hour prior to the blood draw?

The Public Library of Science has a journal called PLoS One. It covers primary research in science and medicine, submissions of which are subjected to intense scrutiny and peer review. However, the Journal does invite post-publication discussion and critique. In its April, 2013 issue, it printed an Icelandic study on consumption of fish products and the risk of prostate cancer. There were almost 2300 men, aged 67 and up, in this four-year project. Except for processed fish that was salted or smoked, fish oil or very high fish consumption was determined not to be associated with early or midlife prostate cancer risk (Torfadottir, 2013). Hmm. Go figure. Earlier Canadian meta-analysis discovered a 63% reduction in prostate-cancer-specific mortality among fish eaters, but no incipient protective effect by fish ingestion (Szymanski, 2010). That means eating fish did not prevent disease. There are other causes, such as too much conventionally raised red meat.

There is a strong suggestion in a Harvard study that total fat and certain saturated fatty acids may be implicated in prostate disease incidence, but that, “Among all men, those with the highest omega-3 docosahexaenoic acid and total marine fatty acid intakes were 40% less likely to die from prostate cancer,” adding that “…high marine omega-3 fatty acid intake may improve disease-specific survival for all men” (Epstein, 2012). Although the source of DHA is not identified in the study in question, an Italian work cited the 22:6 n-3 as protective against physiological activities involved in the progression of prostate cancer cells (Bianchini, 2012).  Marshall University mice that were fed a high n-3 diet containing fish oil concentrate presented with a decreased expression of genes expected to increase proliferation of prostate cancer cells by virtue of lowering estradiol values (Akinsete, 2012).

What about the n-6 to n-3 ratio we mentioned earlier?  Glad you asked. In no particular order, try reading these authors  to get the picture that n-3 fats need the accompaniment of the n-6 fats: (vanJaarsveld, 1997) (Ramirez0Silve, 2011) (Caramia, 2008) (Wijendran, 2004) (Simopoulos, 2002, 2008) (Gomez, 2011) (Yehuda, 1993, 1996). The additional info you need to find these is at the end of this piece. The ideal omega-6 to omega-3 ratio is generally agreed to be 4 to 1. That’s four times the omega-6 as omega-3. How come?  The enzymes that desaturate and elongate fatty acids prefer to work along the n-3 pathway, and by the time they get to the n-6 fats, part of the n-6’s have been burned for energy. Also, the enzyme pathway could be interrupted by age, booze, trans-fats, disease and overdose of dietary cholesterol (which is a good thing that can be overdone).

If fish oil is held culpable, which form?  The ethyl ester form (EE) is made when the glycerol backbone of fish body oil is removed during molecular distillation and replaced by an ethanol, allowing the process to be completed at a lower temperature. It isn’t a fat any more, and really shouldn’t be allowed to be called an oil. This is now an ester that is not digested and absorbed by the body in the same manner as the original triglyceride. Once distilled, true fish oil has its triglyceride put back in a process called re-esterification, or re-concentration, a procedure that adds about 40% to the cost of the finished product. But this replacement of the glycerol—fish oil is a triglyceride—returns the substance to its natural state. Fish oil that has an alcohol head is metabolized just like an alcohol from liquor, and that’s not what we expect from a supplement that’s supposed to be a boon to health. Bioavailability of re-esterified triglycerides is superior to all other forms of fish oil (Dyerberg, 2010).

The study in question (Brasky, 2013) is of an observational nature, not experimental, such as a randomized, controlled, double-blinded trial would be.  Observational studies are not used as reliable sources, though they can help to formulate hypotheses to be used in subsequent experiments (Nahin, 2012). Additionally, cause-effect has not been established. The paper was quick to point the finger at a dietary supplement. True, many supplements are misused for lack of direction by a qualified health care practitioner, such as a dietitian or clinical nutritionist. But that can be resolved with a phone call and an appointment. Mega-doses of fish oil do not mix well with drugs or supplements that thin the blood. If a person doesn’t know that, he needs to. Though there is no established upper limit for fish oil, six grams might be too much, while two or three grams might just be on the mark for most adults. Actual dosage depends on the fish species and the levels of EPA and DHA in the product.

To balance the omega-3 fatty acids, evening primrose oil (EPO) is a good source of omega-6 fats, particularly of gamma-linolenic acid (GLA), which is the preferred launching point for conversion to the longer derivatives. Yes, borage oil has more GLA than EPO, but also contains alkaloids that can tax the liver.

An interesting comment from the University of Guelph in Ontario, Canada is, “I have no idea how this paper got accepted for publication.”  (Professor Gopinadhan Paliyath)

Refere

References

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*These statements have not been evaluated by the FDA.
These products are not intended to treat, diagnose, cure, or prevent any disease.

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