According to a new study, genetic factors play a significant role in whether you will pile on the pounds from eating fried foods. The study was published on March 19 in the British Medical Journal by researchers at Harvard University (Boston, MA) and Albert Einstein College of Medicine (Bronx, NY).
The study authors noted that many factors play a role in obesity; the condition has a genetic basis but requires environmental factors influence to develop. The prevalence of obesity in the US is much higher than other nations, and the high consumption of fast foods is one of the significant differences between the US and the rest of the world. Frying is a common and traditional cooking procedure in Western nations, particularly when individuals dine outside of the home. Fried foods comprise a substantial proportion of the items sold at fast food restaurants that are patronized by approximately a third of Americans every day. The authors note that several previous studies have reported that fried food consumption alone or a Western-style diet pattern, which contains a significant amount of fried foods is positively associated with obesity and related health conditions. However, these studies did not consider the potential modification by an individual’s genetic make-up. They explained that it is unknown whether obesity-related genetic factors can modify the association between fried food consumption and adiposity.
The investigators conducted a study that evaluated the interaction between frequency of fried food consumption (both at home and away from home) and a genetic risk score based on 32 well-established genetic variants associated with body mass index (BMI) and obesity in women and men from two prospective cohorts: the Nurses’ Health Study and Health Professionals Follow-up Study. (A prospective cohort study is one conducted over a period of time among similar individuals.) The findings were replicated in a large independent prospective cohort, the Women’s Genome Health Study. The study group comprised 9,623 women from the Nurses’ Health Study, 6,379 men from the Health Professionals Follow-up Study, and a replication cohort of 21,421 women from the Women’s Genome Health Study. Repeated BMI measurements were made during follow-up.
In both the Nurses’ Health Study and Health Professionals Follow-up Study, the investigators found an interaction between fried food consumption and a genetic risk score based on 32 BMI-associated variants on BMI. Among the participants in the highest third of the genetic risk score, the differences in BMI between individuals who consumed fried foods four or more times a week and those who consumed fried foods less than once a week was found to be 1.0-fold greater in women and 0.7-fold greater in men; among the subjects in the lowest third of the genetic risk score corresponding differences were 0.5-fold greater in women and 0.4-fold greater in men. The gene-diet interaction was replicated in the Women’s Genome Health Study. The genetic association with adiposity was enhanced by a higher consumption of fried foods. In the combined three cohorts, the differences in BMI per 10 risk genes were 1.1-fold greater, 1.6-fold greater, and 2.2 (SE 0.6) for fried food consumption less than once, one to three times, and four or more times a week. The increased risk for obesity per 10 risk genes were 1.61-fold, 2.12-fold, and 2.72 across the three categories of consumption. Furthermore, the variants in or near genes highly expressed or known to act in the central nervous system showed significant interactions with fried food consumption; the FTO (fat mass and obesity associated) variant was found to have the highest interaction.
The authors concluded that their findings suggest that consumption of fried food could interact with genetic background in regard to obesity; thus, underscoring the particular importance of reducing fried food consumption in individuals genetically predisposed to obesity.
Take home message:
Most of us have not undergone a genetic analysis to determine whether we possess obesity genes; however, if you gain pounds easily, this might be a factor. Reducing fried food consumption is beneficial to all individuals whether or not they possess obesity genes.