Along with their many other benefits, omega three fatty acids, primarily found in fish, have now been found protective against the development of heart failure. (Annals of Internal Medicine, 2 August, 2011, pp. 160-170) In adults aged 65 years or older, the incidence of new onset heart failure was substantially lower in subjects with the highest blood concentrations of omega 3 fatty acids. Over an observation period of 10 years, people in the lowest quartile of fish oil concentrations had twice the risk of developing heart failure as those in the highest quartile.
Heart failure is the most common reason for hospitalizations in older adults, and one of the most common causes of death.
This beneficial effect of fish oil likely results from several factors:
- Lower blood pressure
- Increased heart muscle elasticity leading to improved filling during the relaxation phase
- Dilatation of larger blood vessels, with lowering of vascular resistance
- Increased production of nitric oxide to dilate blood vessels
- Increase of HDL (good) cholesterol and lowering of triglycerides
We have been recommending fish oil supplements for years, because of previously known benefits on cholesterol, blood pressure, inflammation, prevention of heart attacks and sudden death, and possible preservation of cognitive function. This recent discovery offers even more reason to take daily fish oil supplements.
How much is enough? There is no upper limit, because no danger from taking fish oil has been documented. We recommend at least 1500 mg daily of EPA/DHA, the listed components on supplement labels. Keep in mind that Eskimos have ingested 10 times that amount on a regular basis, without suffering adverse effects.
Oily fish, especially salmon and tuna, have the highest concentrations of omega 3 fatty acids, but salmon contains lower concentration s of mercury than tuna, and is preferable as a dietary source of oils. The processing of oils in the formulation of fish oil supplements removes heavy metals, and mercury is not present in the finished product. To reduce the toll on the salmon population, supplement companies are utilizing other sources of fish oil, such as krill. These appear to be equally beneficial.
Vegetarians may choose alternative sources of omega 3 fatty acids, such as walnuts, ground flax, or hemp oil. The body does not convert these fats efficiently into EPA and DHA, however, and a generous daily intake is necessary.
Allan Sosin MD