A research team from Kookmin University has discovered a neuroendocrine circuit in the brain that allows animals to dynamically regulate their salt intake based on their internal salt levels. This groundbreaking research, set to be published in the Proceedings of the National Academy of Sciences (PNAS) on February 24, 2026, highlights the brain's role in sensing salt levels directly rather than relying solely on taste. Previously identified sensors in the mouth and esophagus can detect salty tastes, but this research shows that the brain can autonomously limit salt intake when sodium levels are already elevated, maintaining homeostasis.

The research utilized a fruit fly model to demonstrate how specific neurons within the brain can directly detect sodium concentration and modulate rejection responses to excess intake. Key players in this process are two types of neurons: insulin-producing neurosecretory cells and leucokinin neurons, which are the human equivalent of tachykinin. When sodium levels are high, these neurons become activated to prevent excessive salt consumption, demonstrating a feedback mechanism that maintains balance in salt intake. When sodium levels drop, on the other hand, leucokinin signals stimulate the insulin-producing cells to alter preference, promoting the consumption of foods that might otherwise be avoided due to high salt content.

This research holds important implications for understanding dietary salt management and could contribute to further insights into conditions such as hypertension. By clarifying how the brain functions as a 'central sodium sensor,' the study underscores the intricate biological processes that regulate dietary preferences and health outcomes in the context of sodium consumption, potentially guiding future research and public health initiatives aimed at addressing hypertension and related diseases.