The Hunger Hormones
We know from the pioneering practice of Dr. Richard K. Bernstein and the late Dr. Robert C. Atkins that following a low-carbohydrate diet is especially powerful for people with diabetes. When we go on a low-carb diet we have much greater control over our blood glucose. We also have a lot less hunger, making weight loss much easier.
After reading the stimulating new book Good Calories, Bad Calories by Gary Taubes I began to follow a low-carb diet myself. Taubes offered in that book one take on how a low-carb diet works to suppress hunger. I summarized the cascade of events in a recent article here, "How Eating Can Make You Hungry."
In a nutshell, eating carbohydrates stimulates the production of the hormone insulin, which in turn makes us hungry. When we're hungry, we naturally want to eat more, so we gain weight.
But a forthcoming study accepted for publication in the Journal of Clinical Endocrinology & Metabolism implicated a second hormone and a second macro-nutrient as well. This study examined the different effects of carbohydrates, fat, and protein to suppress ghrelin, an appetite-stimulating hormone that the stomach secretes. Just before we eat our level of circulating ghrelin levels increases. Then, it drops right after the meal.
The journal won't be able to publish the study, "Acyl and Total Ghrelin Are Suppressed Strongly by Ingested Proteins, Weakly by Lipids, and Biphasically by Carbohydrates," until April. But the editors thought that it was important enough to make a rapid release version of it available online.
One interesting conclusion, according to the lead author, Dr. Karen Foster-Schubert of the University of Washington School of Medicine in Seattle, Washington, was that when we eat carbs we initially get a strong suppression of ghrelin. But then,"ghrelin levels rebounded well above baseline.”
“Protein consumption resulted in the greatest suppression of ghrelin over a long period," Dr. Foster-Schubert continued. But they discovered in a second interesting conclusion that “when eat eat fat, our level of ghrelin remains relatively high." That, "could in turn stimulate hunger.”
So now we have two macro-nutrients -- carbohydrates and fats -- that can make us hungry. It's a good thing that we can still eat protein.