Thursday, March 15, 2012

Your epigenetics make you fat

I think I have remarked before on this Trinity of sexy themes at the moment in research in health and fitness:
  • Microbiome
  • Mitochondria
  • Epigenetics
This is one for the epigenetics thread:  remember you have genes but the key thing is which of those genes are turned on  and which are turned off.  You are not programmed by you DNA, it is far more complex than that - you have a complex set of switches that react to your environment.

And that applies to your obesity.  You are not programmed to be fat.  Even if you have certain genes that are associated with fatness, they can be overridden.  The environment, epigenetic factors, the signals that you send to your cells,  are so much more important.  So to the study:

Getting Active Blunts Fat Genes

Physical activity appears to dampen the effect of fat-increasing genes, while inactivity allows the genetic disposition to unfold, a longitudinal study found.

Each additional gene variant linked with increasing body mass index (BMI) was associated with a mean gain of 0.13 kg/m2 in BMI, according to Qibin Qi, PhD, from Harvard School of Public Health in Boston, and colleagues.

However, individuals who were most physically active saw a blunted genetic effect, with a mean increase of 0.08 kg/m2, while those watching more than 40 hours of TV per week had an accentuated effect, with a mean increase of 0.34 kg/m2.

Although the genetic effect on BMI was most pronounced at each extreme, it was less so with more benign lifestyles, researchers reported at the American Heart Association's Epidemiology and Prevention/Nutrition, Physical Activity and Metabolism (EPI/NPAM) meeting in San Diego.

For those in the lowest quintile of physical activity, the mean increase in BMI was 0.15 kg/m2 -- a number slightly higher than the reference mean gain associated with each gene variant.

For those who watched up to only one hour of TV per week, the mean gain in BMI was 0.08 kg/m2, the same as in the highest quintile of activity.
 You do not have to be fat.  Get up and move about a bit.

1 comment:

Dr. John said...

Genes are not self-emergent. They just don't switch on without an environmental switch; live in discordance with our ancestral heritage, and disease will occur.
Epigenetics and reaction norms will dictate the phenotype expressed.