High altitudes may reduce diabetes risk, study finds

Researchers at the Gladstone Institutes report that in low-oxygen conditions red blood cells absorb large amounts of glucose, lowering circulating blood sugar and offering a possible explanation for lower diabetes rates seen at higher elevations.

Scientists at the Gladstone Institutes report that living at high altitude may lower the risk of diabetes by changing how red blood cells handle glucose. Their study, published in Cell Metabolism, found that in low-oxygen conditions red blood cells absorb large amounts of glucose and alter their metabolism to deliver oxygen more efficiently. Previous population research of over 285,000 U.S. adults showed lower diabetes prevalence at elevations of 1,500–3,500 meters compared with sea level after adjusting for factors such as diet, age and ethnicity. The team also tested effects in mice and developed a compound called HypoxyStat that reversed high blood sugar in diabetic mice in laboratory tests. Key findings: - In low-oxygen (hypoxic) conditions, red blood cells absorbed substantially more glucose, acting as a previously unrecognized glucose compartment according to the researchers. - Mice exposed to thin air cleared blood sugar rapidly after eating and produced more red blood cells, with each cell taking up more glucose than under normal oxygen. - The researchers used different imaging approaches to identify red blood cells as the site where the missing glucose was held. - The team developed a drug, HypoxyStat, which in laboratory tests reversed high blood sugar in diabetic mice. - The study has limitations: experiments focused on a single mouse strain and on young male mice, and the authors noted that more research is needed to test other strains, females and older populations. Summary: The study points to a previously underappreciated role for red blood cells in whole-body glucose metabolism and offers a possible explanation for lower diabetes rates observed at higher elevations. The authors reported that additional research is needed to determine whether the mechanism is consistent across other animal strains and in females and older people. It is not yet known how these findings might translate into human treatments.