Why Our Hunger Surges with Age
Dr. Andrews’ research indicates that the damage done to appetite-control cells can create cellular instability between messages telling the brain to eat and messages telling the brain to stop eating. The age group determined to be at the greatest risk for these changes fall into the 25 to 50 age range. In many cases, the neurons responsible for telling us not to overeat in that age range are being depleted over time.
When there is an absence of food in the stomach, the hormone ghrelin alerts the brain that hunger is present. Once we’ve consumed enough food and feel satiated, a set of neurons stabilizes feelings of hunger. However, free radicals created by the body begin to attack these neurons leading to a weakening in hunger satisfaction over time.
Dr. Andrews warns that the prevalent carbohydrate and sugar rich diet that has become the norm in modern society has placed a great deal stress on our bodies. Once of the outcomes for this dietary pattern is the premature deterioration of essential cells. He believes that this reduction in appetite-control cells could be one possible explanation for the complex occurrence of adult-onset obesity.
An additional study published in the Journal of Clinical Endocrinology and Metabolism explores the potential of different nutrients to suppress ghrelin, the appetite-stimulating hormone secreted by the stomach. Ghrelin levels typically increase before meals and then decrease shortly after eating food. The researchers discovered that fat consumption caused ghrelin levels to remain relatively high. Protein consumption resulted in the largest suppression of ghrelin over the longest period of time. Interestingly however, carbohydrate consumption led to strong ghrelin suppression initially, though subsequent ghrelin levels later rebounded far above a normal level.
Lead researcher, Dr. Karen Foster-Schubert of the University of Washington School of Medicine in Seattle, Washington, believes that these findings may pave the way to future research on different methods of dieting. If we can improve our understanding of how ghrelin is regulated by ingested macronutrients, this may lead to the design of effective weight-reduction diets.