Are You Hungry or Do You Just Have Cravings?

CNET featured comments from Clinical Professor and Chair for the Department of Interdisciplinary Health Sciences Mindy Haar, Ph.D., RDN, in a story about distinguishing hunger from cravings. Haar explains that the feeling of hunger results from complex communication between multiple organ systems, causing a feeling of emptiness in the gastrointestinal system. The gut and brain communicate with receptors throughout the digestive tract that monitor nutrient levels, signaling to the brain when nutrients are deficient. Cravings, on the other hand, tend to be driven by a psychological component. In addition, consuming foods that would have boosted evolutionary survival (like high-fat and sugary foods) can lead to the brain’s release of dopamine, creating a feedback cycle that can also cause cravings.

“Humans evolved in a way that the desire for sugar and fat was a beneficial characteristic; a sensitivity to sweet tastes allowed individuals to distinguish fruit that was at the peak of freshness and vitamin and mineral content,” said Haar. She also notes that humans evolved to enjoy fat as a means of ensuring survival during times of food scarcity.