Overweight teens: lower blood pressure thanks to Omega 3s

Daily intake of Omega 3 reduces blood pressure values in boys who suffer from mild overweight problems during adolescence. This is shown by a study published in the Journal of Pediatrics, in which researchers from the University of Copenhagen and the Technical University of Denmark in Lyngby, Denmark, showed that 16 weeks of treatment is enough for eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)-the Omega-3s contained infish oil-to reduce blood pressure by 3 mmHg. This, the researchers explain, corresponds to a 15 percent reduction in the risk of stroke in the adult population.

The importance of cardiovascular health in adolescents

It is the study authors themselves who stress the importance of blood pressure control in children. In fact, both children and adolescents who have blood pressure values that are too high are more likely to suffer from hypertension as adults. That's why researchers refer to kids with excessively high blood pressure as "prehypertensives." It is not yet known whether the hypertension from which these boys will suffer as adults is the result of poor eating habits and low physical activity that drag on from adolescence to later ages or whether it is due to actual blood pressure programming that takes place in the under-20s. However, worrying about the problem as early as adolescence is important so as not to compromise health in the years to come.

Omega-3 to help the heart

Omega-3s are excellent candidates for the role of remedies to prevent this type of problem. In fact, the beneficial effect on cardiovascular health of fish oil-a very rich source of these fatty acids-has been known since the 1970s. Its action improves blood lipid concentrations, blood pressure, heart rate and vascular function, while also reducing the risk of thrombosis. For this reason, Danish scholars wanted to test theeffectiveness of EPA and DHA in adolescents. Specifically, the study involved 78 male boys aged 13 to 15 years. And precisely because of what was already known about the beneficial effects of Omega-3s, the authors decided to have only slightly overweight adolescents participate in the research.

A few weeks to protect the future

The teens consumed daily bread containing fish oil in amounts that provided 1.5 grams of Omega-3 per day. At the end of the study, the amount of EPA and DHA found in the red blood cells of these adolescents had increased by 1.2 and 6.7 percent, respectively. In a second group of teens, who, on the other hand, did not take the fish oil, the increase in Omega-3 was only 0.6 percent in the case of EPA and 4.1 percent in the case of DHA. In addition, the researchers found that at the end of 16 weeks in the boys who introduced Omega-3-enriched bread into their diets, systolic blood pressure -- the so-called "maximum" -- had decreased by 3.8 mmHg. At the same time, the value of diastolic blood pressure -- corresponding to the "minimum" -- was also reduced by 2.6 mmHg. In contrast, no effect on the ratio of "bad" (or LDL) to "good" (or HDL) cholesterol was found.

The mechanism of action hypothesis

Based on knowledge regarding the action of EPA and DHA, the study authors hypothesized that the observed effect on blood pressure during adolescence depends on the competition that occurs between Omega-3s and arachidonic acid. The latter, in fact, is the precursor of molecules that, by causing the narrowing of blood vessels, increase pressure values. Conversely, the researchers explain, EPA and DHA could inhibit this mechanism.  

Source 

1. Pedersen MH, Mølgaard C, Hellgren LI, Lauritzen L, "Effects of fish oil supplementation on markers of the metabolic syndrome," J Pediatr. 2010 Sep;157(3):395-400, 400.e1. Epub 2010 May 15