Obesity Gene Trumped by Healthy Diet
With a Healthy Diet, Kids With Obesity Gene Not Destined to Be Fat
March 5, 2009 -- Children born with a gene linked to obesity don't have to
get fat. A healthy diet trumps the obesity gene's unhealthy effects.
People who inherit a variant version of the FTO gene tend to have to
eat more to satisfy their appetites. As a result, they gain excess fat. That's
why FTO has been dubbed the "obesity
The seeds of obesity are planted early in life. But kids with the obesity
gene are not doomed to be fat, says University College London researcher Laura
Johnson, PhD, and colleagues. Children with the FTO variant aren't any
more vulnerable than other kids to the fat-increasing effects of energy-dense,
"Obesity is not inevitable if your genes give you a higher risk,"
Johnson said in a news release. "Those with high-risk genes can, in some
cases, resist their genetic lot if they alter their lifestyle in the right way
-- in this case, their diet."
The findings reinforce what child obesity expert David S. Ludwig, MD, PhD,
told WebMD last year.
"We know that genes affect our body weight set point. But so does our
environment and our diet," Ludwig told WebMD. "We can’t change our
genes, but we can change our diet, and by doing so in a sophisticated way, we
may be able to adjust that body weight set point in our favor."
Energy-Dense Foods, Children, and the Obesity Gene
Energy-dense foods, such as cheese, are dry and/or fatty. They contain more
calories per bite than leaner, more watery foods such as soup.
Adults tend to eat the same amount of food, regardless of its energy
density. Eating a diet rich in energy-dense foods increases obesity risk for
That's not true for kids, Johnson notes. When younger kids eat energy-dense
foods, they generally eat less at the next meal. As they get older, though,
they get more and more like adults.
Might the obesity gene make young children particularly vulnerable to
energy-dense foods? It's an important question, as nearly one in five U.S. kids
aged 6 to 11 years is overweight. So is nearly one in three British kids aged
10 to 11 years.
To get answers, Johnson's team looked at data collected during a long-term
study of 2,275 children who were tested for the FTO gene.
Information on what the kids ate at age 10 was used to determine the energy
density of their diets. Then the researchers looked at how much fat mass the
children had accumulated by the time they reached age 13.
The 13-year-olds tended to be fatter if they had the FTO gene
variant. And they tended to be fatter if they ate an energy-dense diet at age
10. But there was no sign that the obesity gene made energy-dense diets extra
risky for children.
That, Johnson and colleagues conclude, means that kids can offset the risk
of having the obesity gene if their parents feed them fewer energy-dense
How? By doing what they're supposed to do anyway: Replacing high-fat foods
with low-fat foods and giving kids more fruits and vegetables.
The study findings appear in the March 2009 issue of the online journal