Tuesday, October 13, 2009
When Smelling Like a Fish is Worth It (Marin IJ)
October 12th, 2009
For the last several months I’ve been taking a remarkable nutritional supplement that does all of the following:
• Lowers my triglyceride levels and helps keep me trim and lean
• Decreases my risk of developing coronary artery disease (heart disease) and dying suddenly due to a heart arrhythmia
• Alleviates my joint pain and helps keep my mood (more or less) mellow
• Prompts my wife to sometimes tell me “You smell like an aquarium”
No, I haven’t been feasting on our family goldfish. Rather, I’ve been enjoying the myriad benefits of fish oil supplements.
For decades, researchers have wondered why heart disease is much less common among the Japanese than Westerners. While some have proposed a genetic explanation, a 2008 study published in the Journal of the American College of Cardiology seems to suggest otherwise. This investigation found significantly less hardening of the arteries (atherosclerosis) in middle-aged Japanese men compared to middle-aged American men – but only in Japanese men living in Japan. In other words, American men of Japanese descent had similar levels of atherosclerosis as Americans of non-Japanese descent.
What then, was the major difference between the Japanese and the Japanese Americans? Diet. In particular, the blood levels of omega-3 fatty acids (omega-3s) from the consumption of fish species such as salmon, tuna and mackerel. These fatty acids, which are known to biochemists as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), are thought to have anti-inflammatory and anti-clotting properties that deliver significant health benefits. Recent scientific evidence has given omega-3s even more kudos, such that they are well on their way to becoming standard therapy for patients with, or at risk for, heart disease. Consider, for instance, a study published in the Mayo Clinic Proceedings, which found that life-style changes combined with the consumption of fish oil, and red yeast rice decreased LDL “bad” cholesterol levels by 42% – a reduction similar to that seen with the prescription cholesterol-reducing medication simvastatin (Zocor). In comparison to the simvastatin group, the fish oil group had a significant reduction in triglyceride levels (29% vs. 9%). Based on this and other supporting evidence, omega-3s have become the first nutritional supplement ever officially endorsed by the American Heart Association (AHA).
So, the available evidence suggests that omega-3s are beneficial. The next question is how one can smartly and safely incorporate them into their dietary routine. Well, to start with, not all omega-3s are equal – fish-derived sources seem to be more beneficial than plant-based sources (such alpha-linolenic acid – ALA – from flax-seed or olive oil). Unfortunately, studies have demonstrated that certain fish, especially those high in the food chain, have potentially dangerous levels of toxins such as mercury, lead, pesticides (like DDT) and polychlorinated biphenyls (PCBs). Thus, the Japanese approach to eating fish (for breakfast, lunch, dinner and midnight snack) might put you at risk for serious toxicity. And how about fish oil supplements, are they safe? We know that over-the-counter supplements can be dangerous – take, for example, a study of 500 Chinese patent medical products that found that ten percent contained undeclared drugs or potentially toxic levels of heavy metals. But, don’t despair – research suggests that U.S. fish oil products are safe from contamination. A group from Massachusetts General Hospital has tested commercially available preparations of fish oil for toxins (by puncturing the capsules and sending them to the lab for analysis). Luckily, they found undetectable, or nearly undetectable levels of heavy metals (including mercury) and PCBs. One of the brands tested was the brand I personally use, Kirkland, found at the local Costco. The online reviews of the product are stellar, and also suggest an additional benefit:
"I supplement my dog's food with this fish oil,” comments one reviewer, “and it works great to keep his coat shiny. The amazing thing is that is also helps with the ‘doggy’ smell. We used to have to bathe the dog every 2 weeks, but now it is around 2 months before he starts smelling like ‘dog’."
Well, that is pretty remarkable and although I am not sure about the proper dosing for canines, I can tell you that human-based dosing recommendations vary and that people with a history of ulcers or bleeding disorders should be careful because omega-3s do increase the risk of bleeding. In most folks, however, a preventive dose of 250 to 500mg of DHA/EPA per day should be safe and sufficient. The AHA recommends that those with known heart disease take one gram a day and those with high triglycerides may need as much as four grams a day. The main side effect seems to be the occasional fishy burp – which can be alleviated with a hearty meal, a dash of mouthwash, or a dollop of mint jelly.
So, after researching the topic, I have decided to continue my supplementation habit and hope that my wife forgives the occasional whiff of an aquarium. Afterall, one’s heart is more important than one’s breath. Isn’t it?