A new study by University of Colorado School of Medicine has found that people who live at higher altitudes are less likely to die from ischemic heart disease and tend to live longer than others.The researchers, who reported their findings in the Journal of Epidemiology and Community Health, said low oxygen levels and increased solar radiation at high altitudes may be the key to those health benefits.Benjamin Honigman, who led the study said’lower oxygen levels turn on certain genes and those genes may change the way heart muscles function. They may also produce new blood vessels that create new highways for blood flow into the heart. Another explanation could be that increased solar radiation at altitude helps the body better synthesize vitamin D which has also been shown to have beneficial effects on the heart and some kinds of cancer. At the same time, the research showed that altitudes above 4,900 feet were detrimental to those suffering from chronic obstructive pulmonary disease.’For the study, Honigman and his team, which also included researchers from the Harvard School of Global Health, spent four years analysing death certificates from every country in the US.