Fried Foods, Genetic Predisposition Boost Obesity

The adverse effects of fried foods may vary depending on a person’s genetic makeup. Persons with a genetic predisposition to obesity who eat fried foods are at higher risk for obesity-and the chronic diseases associated with obesity-than those without a genetic predisposition, according to the results of a new study.

“Our study shows that a higher genetic risk of obesity may amplify the adverse effects of fried food consumption on body weight, and high intakes of fried food may also exacerbate the deleterious genetic effects. While we expect genetic information may help improve prevention and treatment of obesity in future, currently, we would recommend everyone would reduce intake of fried foods, and other high energy-density, low-nutrient foods, such as sugar-sweetened beverage,” lead author Lu Qi, PhD, an assistant professor in the Department of Nutrition at Harvard School of Public Health and Brigham and Women’s Hospital and Harvard Medical School, told ConsultantLive.

Dr Qi and his colleagues conducted a prospective cohort study to examine the interactions between genetic predisposition and consumption of fried food in relation to body mass index (BMI) and obesity. They analyzed data from more than 9600 women in the Nurses’ Health Study, more than 6300 men in the Health Professionals Follow-up Study, and more than 21,000 women in the Women’s Genome Health Study. Participants filled out food frequency questionnaires that asked how often they ate fried foods both at home and away from home. BMI and lifestyle factors, such as physical activity, were assessed. Genetic risk scores were calculated based on 32 known genetic variants associated with BMI. The age of participants across the 3 studies ranged from 30 years to older than 45 years.

Regular consumption of fried foods was associated with higher BMI, after other dietary and lifestyle factors were taken into account. The association between overconsumption of fried foods and obesity was particularly pronounced among persons with a greater genetic predisposition to obesity. On the other hand, the genetic effect on BMI among those who ate fried foods more than 4 times a week was about twice as large compared with those who ate them less than once a week.

Variants in or near genes “highly expressed” or known to act in the CNS showed significant interactions with fried food consumption; the “fat mass and obesity-associated variant” showed the strongest result. Significant interactions were found irrespective of eating fried food at home or away from home.

The researchers suggest that the association between consumption of fried foods and adiposity is strengthened by genetic predisposition and that the genetic influences on adiposity are amplified by regular consumption of fried foods.

They conclude, “Our findings suggest that consumption of fried food could interact with genetic background in relation to obesity, highlighting the particular importance of reducing fried food consumption in individuals genetically predisposed to obesity.”

The findings indicate that genetic risk of obesity could be mitigated by simply changing an eating habit. The researchers recommend that everyone should be encouraged to adopt healthy eating habits, not just those who are genetically susceptible.

The researchers reported their results online in the March 18, 2014 issue of the British Medical Journal.