Bariatric surgery reduces fasting total fatty acids and increases n-3 polyunsaturated fatty acids in morbidly obese individuals.

BACKGROUND: Obesity is a global pandemic leading to increased mortality and increased risk of cardiovascular disease. Bariatric surgery is an established treatment of obesity leading to weight loss and reduction of mortality. To further elucidate how bariatric surgery improves metabolic control, we explored the fatty acid (FA) profiles in morbidly obese subjects treated with lifestyle intervention and subsequent bariatric surgery.

METHODS: The intervention group consisted of 34 morbidly obese patients scheduled for bariatric surgery and the control group of 17 non-obese patients scheduled for elective laparoscopic procedures. The intervention group had to undergo lifestyle changes preoperatively. Fasting blood samples were drawn at admission, after lifestyle intervention and 1 year after bariatric surgery.

RESULTS: At admission, the morbidly obese patients had significantly higher levels of monounsaturated FAs (MUFAs) and lower levels of n-6 polyunsaturated FAs (PUFAs) and n-3 PUFAs than healthy controls (all p-values <.05). In the intervention group, there was a significantly lower level of total FAs after lifestyle intervention, and from admission to 1 year after surgical intervention (both, p < .05), primarily reflecting a lower proportion of saturated FAs (SFAs). Following bariatric surgery, but not after lifestyle changes, there was an increase in the proportion of n-3 PUFA (p < .05) reaching levels not significantly different from healthy controls.

CONCLUSIONS: Our findings suggest that a reduced proportion of the proposed anti-atherogenic n-3 PUFAs characterizes morbidly obese individuals, and that this FA profile is reversed by bariatric surgery, but not by lifestyle intervention.