Glutton for Sugar? Genes Get Heap of Blame

May 14, 2008 -- Scientists may have found a genetic reason why some people eat more sugar than others.

The key may be a certain variation in the GLUT2 gene, according to researchers including graduate student Karen Eny and associate professor Ahmed El-Sohemy, PhD, of the University of Toronto's nutritional sciences department.

They found that adults with that GLUT2 gene variant reported greater sugar consumption than those with a different variant.

Data came from 100 Canadian adults with type 2 diabetes who weren't taking diabetes drugs and 587 Canadian adults without diabetes. Participants completed dietary surveys and provided blood samples for DNA tests.

The GLUT2 gene variant linked to sugar intake wasn't tied to fat, protein, or alcohol consumption. Those findings held for adults with and without diabetes, regardless of age.

The researchers explain that the GLUT2 gene may help the body sense blood sugar (glucose) levels, and the variant may hamper that process, short-circuiting one of the body's cues to stop eating.

But that doesn't mean that the GLUT2 gene variant drives people to binge on sugar -- or that everyone with a sweet tooth can blame the GLUT2 gene. Observational studies like this one don't prove cause and effect.

Still, the researchers argue that the GLUT2 gene deserves further study for its possible effects on food preferences and disorders affecting food intake.

The findings appear in the May 13 edition of Physiological Genomics.

(Did you inherit your sweet tooth from mom or dad? Or do you prefer salty foods? Share with us on WebMD's Health Cafe message board.)