Genes Are Not Destiny When It Comes To Obesity: Study
TUESDAY, Apr 6th 2010 (CTV News) — An hour a day of moderate exercise can help teens control their weight, even when they are genetically predisposed to obesity, a new European study finds.
The research finds that even those people with a common obesity-related gene dubbed “fatso” can beat their “genetic destiny and maintain their weight with enough daily exercise.
“Fatso” is the unfortunate nickname for the FTO gene, also called the Fat mass and obesity associated gene.
Adults who carry two copies of a mutate form of the gene — who account for about 1 in 6 people in the general population — tend to weigh on average seven pounds more than people who don’t have the gene variant. They also have a 1.67-fold higher rate of obesity than those with no variants of the gene.
For the study released this week in the Archives of Pediatrics and Adolescent Medicine, 752 teenagers from across western Europe had their blood tested for the gene variant. Most of the teenagers had at least one copy of the variant gene:
- 47 per cent had one copy of the obesity mutation
- 16 per cent had two copies
- 37 percent had no copies
The teens wore monitoring devices for a week during waking hours to measure their physical activity.
The study found that exercising an hour or more a day made a big difference for the teens who were genetically predisposed to obesity. Their waist measurements, body mass index scores and body fat were the same, on average, as the other teenagers with regular genes.
But the teens with the gene variant had more body fat, bigger waists and higher BMI if they got less than an hour of exercise daily. The results were similar for boys and girls.
Each mutated gene was associated with an increase of 0.4 per cent in body fat among those who met activity guidelines, compared with a 1.7 percent increase in body fat among those who did not.
The authors note that the U.S. Department of Health and Human Services recently released guidelines recommending that children and teens take part in some of form of moderate to vigorous physical activity for 60 minutes or more, throughout the day.
The researchers wanted to know if those guidelines were enough to combat the effects of “fatso” mutations.
They say their results show that genes are not destiny, and that meeting exercise recommendations may offset genetic predispositions to obesity.
“Indeed, adolescents meeting the daily physical activity recommendations may overcome the effect of this gene on obesity-related traits,” write the researchers, who were led by Jonatan R. Ruiz of the Karolinska Institutet in Huddinge, Sweden.