Health professionals urge people to eat more fish to improve overall health. The American Heart Association recommends eating fish twice a week. Fish contains nutrients called fatty acids that our bodies need but can't produce on their own. Omega-3 fatty acids have been studied as a potential treatment for inflammatory bowel disease (IBD). Some food sources of these fatty acids are included in the table below. Fish oil, which contains omega-3 fatty acids, appears to have anti-inflammatory properties, and has been researched as a treatment for several conditions, including hypertension (high blood pressure) and rheumatoid arthritis.
Omega-3 Fatty Acid Supplements
Fish oil supplements contain two types of omega-3 fatty acids: EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). These two types of fatty acids have anti-inflammatory properties that are important to several processes in the body, including blood clotting and immune function. EPA and DHA also provide other health benefits such as lowering blood pressure and improving cardiovascular health. Patients reported that the troubling side effects from fish oil supplements included bad breath (halitosis), belching, and diarrhea.
Fish Oil as a Treatment for IBD
Fish oil supplements and omega-3 fatty acids have been studied for several years as a complementary or alternative treatment for IBD (Crohn's disease in particular) with varying results. Some researchers suggest that fish oil may work by reducing existing inflammation but that fish oil is not necessarily effective in preventing inflammation.
In one study, 59% of Crohn's disease patients tested maintained their remission after taking fish oil supplements for one year compared to 26% in the placebo group. A second study showed that while taking fish oil supplements, ulcerative colitis patients were able to reduce their doses of prednisone. After stopping the fish oil, patients taking a placebo needed higher doses of prednisone again. A third study compared the effectiveness of sulfasalazine against fish oil for ulcerative colitis. Researchers found that sulfasalazine was more effective than fish oil in treating inflammation for people with mild to moderate ulcerative colitis.
The Bottom Line
The results of these and other studies on the anti-inflammatory effects of omega-3 fatty acids are promising. More research is clearly needed to determine the extent of the anti-inflammatory properties of omega-3s on IBD and other chronic inflammatory conditions.
Belluzzi A, Boschi S, Brignola C, Munarini A, Cariani G, Miglio F. "Polyunsaturated fatty acids and inflammatory bowel disease." Am J Clin Nutr. 2000;71(suppl):339S-342S. Feb 23 2008.
Belluzzi A. "N-3 fatty acids for the treatment of inflammatory bowel diseases." Proc Nutr Soc. 2002;61:391-395. Feb 23 2008.
Belluzzi A, Brignola C, Campieri M, et al. "Effect of an enteric-coated fish-oil preparation on relapses in Crohn's disease." N Engl J Med. 1996;334:1557-1560. Feb 23 2008.
Dichi I, Frenhane P, Dichi JB, et al. "Comparison of omega-3 fatty acids and sulfasalazine in ulcerative colitis." Nutrition. 2000;16:87-90. Feb 23 2008.
Stenson WF, Cort D, Rodgers J, et al. "Dietary supplementation with fish oil in ulcerative colitis." Ann Intern Med. 1992;116:609-614. Feb 23 2008.
Table - Food Sources of Omega-3 Fatty Acids
|Food||Serving Size||Omega-3 Fat|
|Atlantic Salmon or Herring||3 ounces cooked||1.9 grams|
|Blue Fin Tuna||3 ounces cooked||1.5 grams|
|Sardines, canned||3 oz. in tomato sauce||1.5 grams|
|Anchovies, canned||2 ounces drained||1.2 grams|
|Atlantic Mackerel||3 ounces cooked||1.15 grams|
|Salmon, canned||3 ounces drained||1.0 gram|
|Swordfish||3 ounces cooked||0.9 gram|
|Sea Bass (mixed species)||3 ounces cooked||0.65 gram|
|Tuna, white meat||canned 3 ounces drained||0.5 gram|
|Sole, Flounder, Mussels||3 ounces cooked||0.4 gram|
|Wild Catfish, crabmeat, clams||3 ounces cooked/steamed||0.3 gram|
|Prawns||6 pieces||0.15 gram|
|Altantic Cod, Lobster||3 ounces cooked/steamed||0.15 gram|
|Trout, Orange roughy||3 ounces cooked||<0.1 gram|