Study Reveals Overlooked Link Between Blood Cells and Sugar Levels

A recent study conducted by a team of researchers from the Medical University of Vienna has unveiled a previously overlooked connection between blood sugar levels and the proportion of red blood cells, as indicated by hematocrit values. This discovery, published in the journal Science Advances, sheds light on why individuals living at higher altitudes tend to have lower blood sugar levels and fewer diagnoses of diabetes mellitus.

The research indicates that a higher hematocrit level, which signifies a greater percentage of red blood cells in the bloodstream, correlates with reduced blood sugar levels. This finding was unexpected, as previous theories primarily focused on the effects of lower oxygen availability at high altitudes rather than the role of red blood cells themselves.

For endurance athletes, hematocrit levels are crucial, as a higher concentration of red blood cells enhances oxygen transport throughout the body, thereby improving performance. Athletes often elevate their hematocrit through altitude training, where the reduced oxygen concentration at higher elevations stimulates the body to produce more oxygen-carrying red blood cells. However, some athletes resort to the illicit use of erythropoietin (EPO), a hormone that promotes red blood cell production, to artificially enhance their hematocrit levels.

The Vienna research team investigated the effects of simulated high-altitude conditions on overweight mice. They found that the mice exhibited lower blood sugar levels without any significant weight loss, suggesting a direct relationship between increased hematocrit and decreased blood sugar levels. This connection was further confirmed when mice received transfusions of blood with elevated hematocrit values or EPO, resulting in similar reductions in blood sugar.

According to the lead researcher, Clemens Fürnsinn, despite the frequent measurement of hematocrit and blood sugar levels in clinical settings, the direct link between the two has been largely overlooked until now. This novel insight raises questions regarding the potential role of red blood cells in sugar transport and metabolism.

Building on these findings, the research team plans to conduct further studies to explore the underlying mechanisms that drive these observed effects. They propose that manipulating hematocrit levels could potentially offer new therapeutic avenues for managing diabetes in humans.

This research not only advances our understanding of the physiological responses to altitude but also opens up possibilities for innovative treatments for metabolic disorders.