The study compares a group of 10 who were dieting, 6 persons slept for 8.5 hours every night for two weeks and similarly, 4 persons slept for 5.5 hours every night for two weeks. And this was repeated on the same subjects after three months. It was seen that the persons who slept less lost less body-fat more fat-free body mass (such as proteins). In the subjects who lost more fat-free body mass they observed increased hunger, which under normal circumstances, will undermine the efforts of a person dieting.
The conclusion is very clear
Patients attempting to lose weight should consider getting adequate amounts of sleep in addition to limiting calorie intake to ensure that they retain lean muscle mass and lose fat.The conclusion is NOT what The Seattle Times or Los Angeles Times says:
Moral of the study? Put aside the work, or that late-night TV show, and get some shut-eye. Compared to exercise and diet, it's the easiest part of healthy weight loss.Also remember the limitations of the study
All were nonsmokers aged 35 to 49 years, and none were morbidly obese. Patients were followed for only 2 periods of 2 weeks each, much less than the average amount of time people would usually spend on a calorie-restriction program
Nedeltcheva AV, Kilkus JM, Imperial J, Schoeller DA, & Penev PD (2010). Insufficient sleep undermines dietary efforts to reduce adiposity. Annals of internal medicine, 153 (7), 435-41 PMID: 20921542