Fatty fish consumption may improve lipid profile

Increased polyunsaturation in plasma fatty acids and increased HDL diameter were observed in adults who consumed a diet of fatty fish three times a week and regular intake of bilberries and whole grains, according to recent research conducted in Finland.

Researchers reported significant changes, including an association between increased fish intake and increased omega-3 polyunsaturated fatty acids, and a decrease in omega-6 and omega-7 fatty acids.

Researchers analyzed lipid profiles of 106 participants with impaired glucose metabolism and features of the metabolic syndrome who were randomly assigned into one of two intervention groups or a control group. One intervention group, deemed the healthy diet group, was instructed to eat fatty fish three times per week, 100 g of bilberries per day and replace habitual grain products with whole grain varieties. The second intervention group was instructed to replace habitual grain products with the same whole grain products as prescribed to the healthy diet group, but to keep intake of fish and berries unchanged. The control group was instructed to eat normally, and include no more than one meal of fish per week, not consume bilberries and to limit other berries.

Participants engaged in a 2-week period of normal eating habits to establish baseline measurements before beginning their respective diets for 10 weeks. Researchers assessed serum metabolic profiles, which included information on lipoprotein subclasses, lipids and molecular-weight metabolites.

Compared with the control group, participants in the healthy diet group experienced a significant change in lipid metabolites, yielding an increase in polyunsaturated fatty acids and a decrease in omega-6 and omega-7 fatty acids. Additionally, higher fish consumption was associated with larger amounts of large HDL particles, increases in large HDL particle diameter and higher levels of large HDL lipid components, according to researchers. Total HDL cholesterol levels remained unchanged, however.

“People shouldn’t fool themselves into thinking that if their standard lipid levels are OK, there’s no need to think about the diet, as things are a lot more complicated than that. Soft vegetable fats and fish are something to prefer in any case,” postdoctoral researcher Maria Lankinen , MHSc, of the University of Eastern Finland, said in a press release.

Disclosure: See the full study for a complete list of relevant financial disclosures.