A great study recently examined the ability of the macronutrients (protein, carbohydrate and fat) to suppress ghrelin, a hormone known to stimulate the appetite.
Hunger works like this; as blood glucose levels drop ghrelin is secreted from the gut into circulation where it triggers brain cells to promote the sensation of hunger. Ghrelin levels decrease promptly after the consumption of food. The results of this study completed by researchers at the University of Washington School of Medicine in Seattle, suggest that the higher the protein content of the meal, the longer ghrelin levels are suppressed after the meal.
When each of the macronutrients were tested for ghrelin responses, the researches found that dietary fats don't provide any change to ghrelin levels. Carbohydrates promote a large suppression of ghrelin for a short time only to rebound to higher than normal levels soon after. This maybe why people tend to overeat when they follow a carbohydrate-rich diet.
Conversely, the consumption of protein resulted in the greatest suppression of ghrelin over a long period of time. Based on this information, snacking on protein rich foods throughout the day will curb hunger and make fat loss when following a calorie-controlled diet.
This research provides important information on how different nutrients affect our eating patterns and ultimately, our physical appearance. Most importantly, make sure every meal or snack contains a substantial portion of protein.
Source: Journal of Clinical Endocrinology & Metabolism online Jan ’08.