Yeah, this sounds about right - "...genes remember a sugar hit for two weeks, with prolonged poor eating habits capable of permanently altering DNA...

Genes remember sugar hit: Australian research - Yahoo! News:

"Human genes remember a sugar hit for two weeks, with prolonged poor eating habits capable of permanently altering DNA, Australian research has found.

A team studying the impact of diet on human heart tissue and mice found that cells showed the effects of a one-off sugar hit for a fortnight, by switching off genetic controls designed to protect the body against diabetes and heart disease..."