Researchers study obesity by assessing ghrelin levels in biological samples.

Activity in the lateral prefrontal cortex was the best correlate of weight loss in a study of people on a restricted-calorie diet.

Changes in diet can cause gut microbes to produce acetate, which in turn stimulates insulin secretion and obesity in rodents, scientists show.

Ghrelin promotes fat storage not feeding, according to a study.

Signs of getting older are less common among rodents with ramped-up ghrelin production.