It's Not Your Fault

WaPo: Weight Gain May Not Be Based Just on What You Eat

THURSDAY, June 5 (HealthDay News) -- "You are what you eat" is a frustrating truism familiar to the diet-conscious choosing between carrots and carrot cake. But new research suggests that weight control isn't just a matter of what you put in your mouth, but also how the nervous system is genetically predisposed to process fat.

The theory is based on research with worms that suggests that the brain chemical serotonin -- long known for its appetite control properties -- relies on independent but coordinated nerve pathways to drive not only hunger, but also fat metabolism.

"I want to be clear that there is absolutely nothing in our study that says that good nutrition and activity is not important or not good for you," said study lead author Kaveh Ashrafi, an assistant professor in the department of physiology and the Diabetes Center at the University of California, San Francisco. "But that said, I think that it is important to realize that there is a major contributing factor to body weight that is genetic."