fat

These modified mice produced a slightly altered version of a liver protein that affects hundreds of genes involved in fat metabolism.

"Slim individuals on restrictive diets tend to lose muscle more than fat," he says.

To address the problem, shipping companies have begun offering fat signing bonuses.

Researchers report that people who have more muscle and a lower visceral fat to muscle ratio tend to show signs of a younger biological brain age.

The winners were niche budget airlines and the big four — American, Delta, United and Southwest Airlines — which by the 2000s had already cut the excess fat from the passenger experience.