A daily dose of 3.36 grams of the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) led to a decrease in the expression of genes linked to inflammation and an increase in anti-inflammatory compounds in fat tissue, according to findings published in the American Journal of Clinical Nutrition.
“This is the first randomized controlled clinical study, which shows that treatment with long-chain n-3 PUFAs alleviates obesity-associated chronic inflammation of [fat tissue] in severely obese non-diabetic patients, as quantified by local gene expression and systemic levels,” wrote researchers from Medical University of Vienna.
However, the study’s results should be interpreted with caution, given limitations in the study design, said Harry Rice, PhD, VP of regulatory and scientific affairs for GOED.
Dr Rice told NutraIngredients-USA that he has little doubt that the long-chain O-3s reduce inflammation, but he is hesitant to say this research provides much support.
“Because there were no adipose tissue biopsies obtained at baseline, there's no way to determine the effect of Omega-3s on adipose tissue inflammation over time. Even if that was not a concern, the control group received 5 grams per day of butter. How can one say with any certainty that the demonstrated anti-inflammatory effect is not really a pro-inflammatory effect?
“The investigators dismissed the potential pro-inflammatory contribution from the additional butter because the average butter intake in Austria is 10g/person/day.
“I don't understand how they can discount the potential inflammatory contribution associated with a 50% increase in butter consumption!”
The Vienna-based scientists recruited 55 severely obese non-diabetic patients and randomly assigned them to receive either 3.36 grams per day of EPA and DHA or an equivalent amount of butterfat for eight weeks.
Results of the randomized open-label controlled clinical trial indicated that the participants in the omega-3 group displayed a decrease in the expression of most of the genes linked to inflammation in fat tissue. In addition, anti-inflammatory eicosanoid production was increased in fat tissue.
The researchers also noted a “striking reduction” in the ration of omega-6 to omega-3 fatty acids, “a valuable surrogate marker for the level of chronic obesity-associated low-grade inflammation”.
This, they said, “is of great prognostic relevance, because it is likely that a high intake of widespread n-6 PUFAs without counteracting n-3 PUFAs”.
Source: American Journal of Clinical Nutrition
Published online ahead of print, doi: 10.3945/ajcn.112.037432
“Long-chain n–3 PUFAs reduce adipose tissue and systemic inflammation in severely obese nondiabetic patients: a randomized controlled trial”
Authors: B.K. Itariu, M. Zeyda, E.E Hochbrugger, et al.