Fish consumption may be associated with increased body mass

Marine foods are the sole dietary source of long‐chain omega 3 fatty acids (LCn3FA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which incorporate into membrane phospholipids, competing for the sn ‐2 position with arachidonic acid (AA). Increased dietary LCn3FA favors, by competitive inhibition, the 3,5‐series eicosanoids and reduces the 2,4‐series eicosanoids derived from AA. The latter eicosanoids are proinflammatory and linked to cardiovascular disease (CVD) and dementia. The American Heart Association recommends fish consumption twice weekly to reduce CVD risk and up to 4 g EPA+DHA daily for patients with CVD. Moreover, experts support fish oil supplementation for treatment of mental disorders. Yet, recent animal data implies that competitive inhibition of the AA cascade by LCn3FA may negatively influence body weight. We recently reported on fish consumption and mood. These data were reexamined to explore associations between fish consumption, dietary LCn3FA, and body mass. In one sample (47 M/72 F; 32.5±7.9 y), body mass index (BMI) was 11% higher in fish eaters (n=97) versus fish avoiders (25.7±4.8 and 23.2±3.2 kg/m 2 , p=0.050) after controlling for age, gender, and physical activity. In a second sample (58 M/71 F; 43.0±11.9 y), BMI was 9% higher in fish eaters (n=63) versus fish avoiders, (27.4±6.1 and 25.2±4.7 kg/m 2 , p=.032). Vegetarians comprised ~50% of this sample, and significance was lost after controlling for diet type. However, in the omnivores, there was a correlation between dietary LCn3FA and BMI (n=71; r=.246, p=.039). These data support a link between LCn3FA and BMI and suggest that although a number of health benefits have been associated with fish consumption, high intakes of LCn3FA may not favorably influence BMI. Research funding was provided by the ASU Foundation.