Gene Helps Turn Carbs Into Fat

A gene determines whether highly processed carbs get stored as fat or burned away. But deactivating the gene to prevent fat build-up has its own problems. Cynthia Graber reports.

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It’s no secret that there’s an obesity epidemic going on.  Many researchers blame highly processed carbohydrates, such as high-fructose corn syrup and white flour.  Now scientists at the University of Wisconsin in Madison have started to tease out the role of the liver in converting those calorie-rich foods into fat. The researchers isolated a gene in the liver called SCD-1. The gene codes for an enzyme that synthesizes fatty acids.  Mice with the normal gene were fed a diet high in processed carbs.  The mice converted those carbs into fat and stored that fat in the body.  But mice that lacked that SCD-1 gene just burned all those carb calories.  And stayed skinny. 

This finding reveals that the liver determines whether or not eating refined carbohydrates will lead to fat gain.  The researchers say this system is a good example of a direct diet-gene interaction. But they also say that a drug to turn off that fat-making liver gene  wouldn’t be a good idea.  Without that gene, the mice could no longer make glucose. They ended up hypoglycemic—suffering from low blood sugar.  So the solution is, sadly, what you already knew: eat fewer processed carbohydrates.

—Cynthia Graber 

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