People who live at high altitude have remarkably low rates of diabetes. For years, researchers assumed this was due to diet, genetics, or increased physical activity in mountainous terrain.

Turns out, it's something far more fundamental: their red blood cells are hoarding glucose.

Researchers at Gladstone Institutes discovered that in low-oxygen environments—like those at high altitude—red blood cells shift their metabolism to absorb glucose from the bloodstream far more efficiently than they do at sea level. In mice exposed to hypoxia, blood sugar "disappeared from their bloodstream almost instantly" after a meal, according to the research team.

The mechanism is surprisingly elegant. When oxygen is scarce, red blood cells need to maximize oxygen delivery to tissues. To do that, they produce molecules that help hemoglobin release oxygen more readily. But synthesizing those molecules requires energy—and that energy comes from glucose.

So at high altitude, your red blood cells essentially become glucose sponges. They pull sugar out of circulation to fuel the metabolic machinery that keeps your tissues oxygenated.

This isn't a minor effect. The researchers initially thought major organs—liver, muscle, fat tissue—would account for the rapid glucose clearance they observed. But the numbers didn't add up. Using imaging techniques, they identified red blood cells as the "hidden compartment" nobody had been tracking.

Dr. Isha Jain, who led the study, noted: "Red blood cells represent a hidden compartment of glucose metabolism that has not been appreciated until now."

The research, published in Cell Metabolism, involved collaborators from the University of Colorado and University of Maryland.

Now here's where it gets interesting: the team tested a drug called HypoxyStat, developed in Dr. Jain's lab, that mimics the effects of low oxygen by making hemoglobin bind oxygen more tightly. In diabetic mice, the drug performing even better than existing diabetes medications.