March 19, 2014
Genetics And Obesity – Fried Foods Can Sometimes Raise Risk Factors
Brett Smith for redOrbit.com - Your Universe Online
Conducted by a team of American researchers, the new study found that consuming fried food over four times a week had double the effect on body mass index (BMI) for those with the highest levels of known genetic risk factors compared with those who showed lower amounts of these genetic markers.
"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," said study author Lu Qi, an assistant professor of nutrition at Harvard Medical School.
The authors of an editorial published alongside the new study put it more simply: bad genetics can inflate the negative effects of a poor diet.
To reach their conclusion, the study team analyzed information from over 9,600 women in the Nurses' Health Study, nearly 6,400 men in the Health Professionals Follow-up Study and more than 21,000 women in the Women's Genome Health Study. Volunteers completed food frequency surveys that asked how frequently they ate fried foods they either made at home or had bought from a restaurant. The researchers identified three categories of fried food consumption: less than once a week, one to three times a week, and four or more times a week.
Height and body weight, used to figure BMI, were determined at the start of the trials, and weight was asked for at each follow-up. Lifestyle factors, such as levels of physical exercise, were also evaluated. Genetic risk scores, which ranged from 0 to 64, were based on the presence of 32 genetic variants connected with BMI.
Among volunteers in the highest third of the genetic risk score, the differences in BMI between people who ate fried foods four or more times a week and people who ate them less than once a week were 1.0 in women and 0.7 in men. For volunteers in the lowest third of the genetic risk score, the differences were 0.5 in women and 0.4 in men.
The authors emphasized that their outcomes could have been impacted by unmeasured or unidentified factors, despite the fact that they carefully adjusted for quite a number of diet and lifestyle variables.
However, the team said they showed that the connection between fried food intake and higher BMI may fluctuate according to inconsistencies in genetic predisposition and vice versa; that genetic risk for an elevated BMI may be tweaked by fried food intake.
"Our findings emphasize the importance of reducing fried food consumption in the prevention of obesity, particularly in individuals genetically predisposed to (elevated BMI),” Qi said.
"This work provides formal proof of interaction between a combined genetic risk score and environment in obesity," Alexandra Blakemore and Dr. Jessica Buxton, from the Imperial College London, wrote in an editorial. However, they added that the results "are unlikely to influence public health advice, since most of us should be eating fried food more sparingly anyway."
The editorial also called for future research on "providing clinically useful predictions for individuals and enabling stratification of patients for appropriate care and treatment."