Overweight teenagers: lower blood pressure thanks to Omega 3

Daily intake of Omega 3 reduces blood pressure values in teenagers who suffer from mild overweight problems. This was demonstrated by a study published in the Journal of Pediatrics, where researchers from the University of Copenhagen and the Technical University of Denmark in Lyngby (Denmark) showed that just 16 weeks of treatment with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) – the Omega-3s found in fish oil – reduce blood pressure by 3 mmHg. According to the researchers, this corresponds to a 15% reduction in stroke risk in the adult population.

The importance of cardiovascular health in teenagers

The authors of the study emphasize the importance of controlling blood pressure in young people. Indeed, both children and adolescents with high blood pressure values are more prone to suffer from hypertension as adults. For this reason, the researchers define teenagers with high blood pressure as “prehypertensive.” It is not yet clear whether the adult hypertension in these individuals results from poor dietary habits and low physical activity carried from adolescence into later life, or whether it is due to a true programming of blood pressure that occurs before age twenty. Nevertheless, addressing the problem during adolescence is important to avoid compromising health in the years ahead.

Omega-3 to help the heart

Omega-3s are excellent candidates as remedies to prevent this type of issue. Indeed, the cardiovascular benefits of fish oil – a very rich source of these fatty acids – have been known since the 1970s. Its action improves blood lipid concentrations, blood pressure, heart rate, and vascular functions, also reducing the risk of thrombosis. For this reason, the Danish researchers wanted to test the effectiveness of EPA and DHA during adolescence. Specifically, the study involved 78 male teenagers aged 13 to 15 years. Given the known benefits of Omega-3s, the authors chose to enroll only slightly overweight adolescents in the research.

Few weeks to protect the future

The teenagers consumed daily bread containing fish oil in amounts sufficient to provide 1.5 grams of Omega-3 per day. At the end of the study, the levels of EPA and DHA found in the red blood cells of these adolescents increased by 1.2% and 6.7%, respectively. In a second group of teenagers who did not consume fish oil, the Omega-3 increase was only 0.6% for EPA and 4.1% for DHA. Furthermore, the researchers observed that at the end of the 16 weeks, the systolic blood pressure – the so-called “top number” – in the group eating the Omega-3-enriched bread decreased by 3.8 mmHg. At the same time, diastolic blood pressure – the “bottom number” – was reduced by 2.6 mmHg. No effect was observed on the ratio between “bad” (LDL) and “good” (HDL) cholesterol.

The hypothesized mechanism of action

Based on knowledge of EPA and DHA action, the study authors hypothesized that the observed blood pressure effect during adolescence depends on the competition between Omega-3s and arachidonic acid. The latter is the precursor of molecules that cause blood vessel constriction, thus increasing blood pressure values. Conversely, EPA and DHA could inhibit this mechanism, explain the researchers.  

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