Dr John Briffa: Cod almighty

While many believe nutritional supplementation to be a strictly contemporary phenomenon, this is actually far from the truth. Cod liver oil, for instance, has been advocated for its bone-building and joint-feeding effects for more than 100 years, and some of us may even remember being plied with a daily spoonful when we were young. However, cod liver oil's popularity has waned of late, largely as the result of the stiff competition it has faced from a growing number of pills and potions that cram the shelves of health food stores and pharmacies. It seems that cod liver oil's reputation as a stalwart supplement has been diluted by the wash of natural remedies that vie for our patronage and pound.

Despite its sinking standing in the natural-remedy ranks, there is much about cod liver oil that is worthy of our attention. Its chief ingredients are the omega-3 fats, specifically docosohexaenoic acid (DHA) and eicosapentaenoic acid (EPA). DHA and EPA can thin the blood, reduce the level of unhealthy blood fats known as triglycerides, raise levels of 'healthy' high density lipoprotein (HDL) cholesterol and help reduce blood pressure. Studies have linked goodly omega-3 consumption (from fish or fish oil supplementation) with a reduced risk of heart disease and stroke.

Another effect the omega-3 oils have is to quell inflammation. Interestingly, there is mounting evidence that inflammation is an important underlying mechanism in heart disease and stroke. The natural anti-inflammatory effect of the omega-3 fats may play some part in their apparent ability to keep circulatory disease at bay. Its potential to dampen inflammation means cod liver oil may also be an anti-arthritic agent. In one study, daily supplementation for three months brought about significant reductions in the stiffness and pain caused by rheumatoid arthritis, the inflammatory joint condition.

It may also be useful in the treatment of osteoarthritis, which is characterised by 'wear and tear' in the cartilage that lines the joints. In addition to its rich catch of omega-3 fats, cod liver oil also offers useful quantities of vitamin D, which plays an important role in the health of the bones and joints. Research shows that those with the highest intake of vitamin D have the lowest risk of suffering from degeneration in their joints. Vitamin D has been linked with protection from other conditions, too, including cancers of the breast, colon and prostate.

Most of our needs for vitamin D are met by the action of sunlight on our skin. But as the days shorten, the opportunity to make sufficient vitamin D from the sun declines. For this reason, cod liver oil makes an ideal supplement for use from the autumn until spring. Take 2-3 tsps (10-15 mls) each day (perhaps mixed into a little orange juice to disguise the taste). Even in the swelling sea of supplements, I reckon cod liver oil remains a very big fish indeed.

Thanks to guardian.co.uk who have provided this article. View the original here.