Molecular and Neural Bases of Nutrition-Based Feeding Decision-Making

Obesity and life style-related diseases have become major burdens to global health. Not having effective diet therapy that patients can adhere to makes life-style modification difficult. Many diet therapies are developed based on solid scientific evidence in terms of nutrition. However, how to execute such nutritionally-effective diet therapy is not established, nor based on solid science. Current practices are mostly developed by trial-and-error (experience-based), and they do not have solid bases on how eating behavior is regulated. Therefore, one of the major bottlenecks for implementing nutritionally-effective diet therapy is our lack of understanding of the molecular and neural bases of eating behavior. Based on the concept of nutrition, we eat to maintain homeostasis, and therefore, we should be satisfied once the needs are met by the supplies. However, that is only a part of the picture regarding eating. Palatable foods, which stimulate the hedonic system, and the experience-based prediction system work in concert to regulate eating. The information that conveys needs and supplies is multi-modal, each mode working at different timing to modulate each system. Therefore, eating behavior is complex, and the whole picture remains elusive. In particular, how we sense, calculate, and predict the needs and supplies of calories and each macronutrient remains to be understood. In this minireview, the frontiers in our understanding of the mechanism that regulates eating are briefly overviewed, as a summary of the IUNS-ICN symposium entitled "Molecular and neural bases of nutrition-based feeding decision-making."