In 2015, for the first time in two decades, life expectancy declined in the USA. Obesity appears to have a major role along with the rising rates of eight leading causes of death, including heart disease, stroke, diabetes and dementia, the latter of which rose by 15.7 percent rise between 2014 and 2015. These data from the National Center for Health Statistics (NCHS) show life expectancy for both men and women in the U.S. dropped between 2014 and 2015, from 76.5 years in 2014 to 76.3 in 2015 for men, and from 81.3 to 81.2 for women. This decline in life expectancy seems a uniquely American phenomenon. No other developed countries experienced this decline.
A 2021 study aimed to estimate the changes in life expectancy and years of life lost in 2020 associated with the covid-19 pandemic. A reduction in life expectancy in men and women was observed in all the countries studied except New Zealand, Taiwan, and Norway, where there was a gain in life expectancy in 2020.