Manage the Hunger Hormone

Ghrelin is a recently discovered hormone produced by the stomach and other parts of the gastrointestinal (GI) tract. High levels of this hormone are released by the GI tract into the blood and correlate with subjective feelings of hunger. When ghrelin is given to people intravenously, it increases their hunger level and causes them to eat significantly more calories at meal than when given a placebo. Ghrelin is one of the first hormones that has been shown to stimulate appetite. It seems to be involved in shot-term satiety after a meal and in long-term hunger and food intake regulation as well. It is one of the most promising biomarkers yet discovered for hunger and food intake regulation.1

When people lose weight on calorie-restricted diets, ghrelin levels increase and people report they are hungrier than before they lost the weight. In one study ghrelin levels rose 24% after subjects lost 17% of their initial body weight. Eating food dramatically lowers ghrelin levels in the blood and eliminates hunger. But simply drinking water does not lower ghrelin levels and does not reduce hunger. Not all foods have the same impact on ghrelin levels.• Ghrelin levels drop in proportion to the amount of carbohydrate in a meal or snack.• The consumption of fat or a fat-rich meal does not suppress the release of ghrelin nearly as effectively as does a meal with more carbohydrate and little fat. This may explain why most people who lose body fat and keep it off do soon fat-restricted diets.2• Fructose, like fat, suppresses ghrelin less than glucose suggesting it too may contribute to overeating and weight gain.3Bottom Line: Research on ghrelin suggests that people are more likely to be able to control their appetites and lose weight and keep it off without having to deal with increased hunger if they consume less fat and fructose.By James Kenney PhD, RD, LD, FACN.1. Am J Clin Nutr 2004;79:946-612. J Clin Endocrinol Metab 2003;88:1577-883. J Clin Endocrinol Metab 89(6):2963–2972