For the last several weeks, I have had one 6 oz. serving of salmon everyday in hopes of improving my omega 3-6 ratio. As you might already know, omega 3 and omega 6 fatty acids have opposing physiological functions: omega 6s generally are metabolized into pro-inflammatory prostaglandins, and omega 3s are metabolized into anti-inflammatory prostaglandins. Considering the key role played by inflammation in the pathogenesis of MPB, anyone's hair loss regimen would be improved by a diet that has a favorable n3-n6 ratio. The modern western diet contains so many foods high in omega 6 that the typical n6:n3 ratio is somewhere from 20:1 and 40:1.
Recently though I've read about the dangers of the organic form of mercury (methylmercury) which occurs in predatory fish like salmon and tuna. I've learned that while inorganic forms of mercury like the stuff released from dental amalgams accumulates in target tissues like the kidneys, liver, and CNS. The distribution of organic forms is much more diffuse, and one place where it accumulates is the skin - right in the hair follicles. Check out this bit:
Chenyang Shi*, Alfred T. Lane† and Thomas W. Clarkson*
*Environmental Health Sciences Center, School of Medicine and Dentistry, University of Rochester, Rochester, New York 14642 USA
†Department of Dermatology and Pediatrics, School of Medicine and Dentistry, University of Rochester, Rochester, New York 14642 USA
Received 10 August 1989.
Available online 4 May 2005.
Human hair has unique advantages in monitoring environmental exposures to methylmercury. Using newborn Balb/c mice as a model system, the incorporation of methylmercury into the hair was studied and compared with methylmercury distributions in other tissues. Newborn mice were given intraperitoneal injections of 203Hg-labeled methylmercury at designated times according to hair growth stages of the mouse. Animals were sacrificed 2 days after dosing. Distribution of mercury in pelt and other tissues was measured. The level of mercury in pelt was found to correlate with hair growth. The amount of mercury in pelt peaked when hair growth was most rapid and the total amount of mercury in pelt was significantly higher than that in other tissues, constituting 40% of the whole body burden. However, when the hair ceased growing, the amount of mercury in pelt dramatically dropped to 4% of whole body burden and mercury concentrations in other tissues except brain were elevated. Autoradiographic studies with tritium-labeled methylmercury demonstrated that methylmercury concentrated in hair follicles in the skin. Within hair follicles and hairs, methylmercury accumulated in regions that are rich in high-sulfur proteins. The uptake of inorganic mercury (administered as HgCl2) by pelt was also compared with that of methylmercury. The amount of inorganic mercury found in pelt was less than one-half that of methylmercury in animals with growing hair. Cessation of hair growth did not decrease the inorganic mercury level in pelt to the same extent as in the case of methylmercury.
1Part of this study was presented at the 28th Annual Meeting of the Society of Toxicology, Atlanta, GA, February 27–March 3, 1989, and was published in an abstract form.
There is convincing evidence that if foods contaminated with mercury are accompanied by sufficient amounts of selenium (either within the food itself or through dietary supplementation), then the selenium has a protective effect against mercury toxicity. This is probably because selenium is important for the endogenous synthesis of the anti-oxident glutathione. Mercury has a high affinity for the sulfhydryl groups in thiols like glutathione and cysteine. Here's the catch: once mercury binds to glutathione or other thiols, it is not necessarily excreted from the body. In fact, evidence shows that glutathione and other thiols enhance absorption and retention of mercury. The protective effect of anti-oxidants like glutathione is probably due to the fact that it transports the mercury from critical tissues like the kidneys, liver, and CNS to less critical ones like muscle tissue and skin. Unfortunately for those of us in the MPB club, mercury accumulating in the skin is bad news for our hair follicles. And as the article above states, methylmercury accumulates in the skin and hair follicles. There is now a growing body of evidence that oxidative stress is a crucial factor in the pathology of MPB.
Thus I'm going to stop with the salmon...maybe I'll have it just a few times per month because it is such a great-tasting and healthy food containing many important nutrients. But salmon was also my major source of dietary omega-3s. There are relatively few foods that have good amounts of omega3: fatty fish, flaxseed, walnuts, and vegetables like broccoli and spinach. Of course, the DHA- and EPA-forms of omega 3 found in fatty fish have been proven to be far more beneficial for health than the omega 3s from the plant sources I listed.
At this point I'm unsure of what to do about maintaining a good n6:n3 ratio. I guess I could up my daily dosage of krill oil to around 1.5 grams...but that still doesn't even come close to the 3-4 grams I was getting from salmon. Tom, what do you try to eat in order to maintain a good n3:n6 ratio?