Fish vs. Fish Oil Capsules

We know that eating fish that are high in omega-3 and omega-6 fatty acids can have a profound effect on your health, from bones to brain to heart. A couple of years ago we reported on several studies (5/3/06, 10/24/06, 11/17/06) comparing the effects of eating fish high in omega-3 fatty acids with the effects of those oils in capsule form.

While the studies showed that the fish oil supplements seemed to have similar effects on health to eating fatty fish, what we don't know is whether the fatty acids in capsule form are absorbed by the body as easily as those from fish.

Researchers at Saint Luke's Mid America Heart Institute and the University of South Dakota (Am J Clin Nutr 2007;86:1621-5; funded in part by a grant from the National Fisheries Institute) recruited 23 premenopausal women of normal weight and randomly assigned them to one of two groups: a fish group and a capsule group. The fish group was supplied with specific amounts of tuna and salmon to eat twice per week, while the capsule group was given fish oil capsules to take 1-2 times per day, according to a specific schedule. The amount of fish and the amount of fish oil in the capsules was designed to contain the same amount of omega-3 and omega-6 fatty acids per week, regardless of whether the volunteer ate fish or took supplements.

To find out whether the fish oil in the capsules was absorbed by the body as well as the fish oil in the fish, the scientists conducted blood tests every two weeks throughout the 16-week study and compared the results of the supplement group to the fish group. In the short term - the first four weeks of the study - it seems that the omega-3 fatty acids supplied from fish had a greater effect on cholesterol levels and red blood cells than did the fish oil capsules, which suggests that the omega-3 fatty acids from fish are more easily absorbed by the body. That said, they found that over the full length of the study, the difference between the effects of the fish and the supplements was not significant.

What this means for you

This is good news for those who don't like fish: fish oil supplements appear to be just as easily absorbed by the body as the same amounts of fatty acids in fish. If you do eat fish, however, why take pills when there are such delicious things to eat? Try Saffron Salmon Risotto - it's great to take for lunch. Or how about some Seared Red Pepper Barbecue Tuna?

First posted: April 30, 2008