Researchers have linked the MC4R gene with people's preference for fatty or sugary foods, BBC News reports.
Researchers led by the University of Cambridge's Sadaf Farooqi offered volunteers — 14 who had a loss-of-function mutation in MC4R and 20 lean and 20 obese individuals — three versions of chicken korma. The dishes had varying levels of fat, but with a similar appearance and, as far as possible, taste. They similarly offered another set of volunteers three versions of Eton mess, a dessert with strawberries and cream, with varying levels of sugar. The volunteers tried each version of the dish, and then could choose what they ate more of.
As they report in Nature Communications, Farooqi and her colleagues found that people with a defective MC4R gene, who thus lack the melanocortin-4-receptor prefer high-fat foods, but not high-sugar foods. This, they add, suggests that central melanocortin circuits are involved in fat and sucrose preference in people.
"Having a pathway that tells you to eat more fat at the expense of sugar, which we can only store to a limited extent in the body, would be a very useful way of defending against starvation," Farooqi tells the BBC.