‘Hunger Hormone’ Ghrelin Affects Monetary Decision Making

Summary: Higher levels of the hunger hormone ghrelin predict a greater preference for smaller, immediate financial rewards over larger, delayed financial rewards.

Source: The Endocrine Society.

Higher levels of the stomach-derived hormone ghrelin, which stimulates appetite, speculate a greater preference for smaller instant monetary rewards over larger delayed financial rewards, a new study finds.

According to Franziska Plessow, the research presents new evidence in humans that ghrelin, known as “hunger hormone”, affects monetary decision making. She said that in a recent research detection in rodents proposed that ghrelin may play an important part in spontaneous choices and behaviors.

Ghrelin signals the brain for the need to eat and may regulate brain pathways about control reward processing. Levels of ghrelin keeps fluctuating throughout the day, which depends on food consumption and individual metabolism.

This study was carried out on 84 female participants between ages 10 to 22 years: 50 with a low-weight eating disorder, such as anorexia nervosa, and other 34 health control participants. The research team tested blood levels of total ghrelin prior to and after having a standardized meal that was similar for all participants, who had fasted beforehand.

After the meal, participants were tested on hypothetical financial decisions, called the delay discounting task. They were asked to make a series of choices to indicate their preference for a smaller instantaneous monetary reward or later a larger amount of money, for instance, $20 today or $80 in 14 days.

The researchers reported that healthy girls and young women with richer ghrelin levels were more likely to choose the instantaneous but smaller monetary reward rather than waiting for a larger amount of money. This preference indicates more impulsive choices.

The relationship between ghrelin level and monetary choices was lacking in age-matched participants with an under wait eating disorder. People with this eating disorder are known to have ghrelin resistance, and Plessow said their finding might be another indicator of a disconnect between ghrelin indication and behavior in this population.