Now, researchers say that stubborn belly fat could also sabotage a person's diet by churning out a powerful appetite stimulating hormone.
Scientists at the University of Western Ontario made the discovery in rats but suspect the same thing is happening in humans.
The fat cells within the abdomen produce a hormone called Neuropeptide Y or NPY, which, previously, was thought to originate only in the brain.
The findings could lay the ground work for easier therapies to use that will only target belly fat.