The United States is expected to make only minor gains in life expectancy over the next few decades, highlighting an "alarming trajectory of health challenges" facing the country, researchers say.
Life expectancy in the US is projected to increase from 78.3 years in 2022 to 80.4 years in 2050, according to forecasting models from the University of Washington's Institute for Health Metrics and Evaluation.
For the analysis published in The Lancet, researchers assessed the impacts of hundreds of diseases and other health risks on the US and individual states, comparing them to more than 200 other countries.
The study found that the US would lag behind most other high-income nations and some middle-income nations in life expectancy gains. In terms of overall life expectancy, the US is expected to fall to 66 out of 204 countries assessed by 2050, down from 49th in 2022.
Life expectancy among women in the US is predicted to improve less than men's, narrowing the gender gap. The forecast suggests a drop from 51st to 74th for women and from 51st to 65th for men by 2050.
"The slight increase in US life expectancy that's forecasted for 2050 is driven by a predicted decline in mortality due to a few leading causes of death, including heart disease, stroke and diabetes," according to IHME.
Addressing key risk factors could significantly improve US life expectancy. Lower rates of obesity, smoking, and drug use disorders could each lead to about a half-year increase by 2050.
"In spite of modest increases in life expectancy overall, our models forecast health improvements slowing down due to rising rates of obesity," Christopher Murray said. "The rise signals a public health crisis of unimaginable scale."
GLP-1 medications are gaining popularity with promising outcomes; however, their future uptake remains uncertain as they were not included as a factor by IHME.
"Drug overdose deaths have started declining after reaching record levels," Ali Mokdad noted. "However, levels remain high and will likely increase over decades."
If risk factors such as environment, behavioral risks, metabolic risks, childhood nutrition and vaccination were eliminated there would be about 550 thousand fewer deaths by 2050 alone - potentially bringing U.S. life expectancy up nearly four years aligning with Canadian projections according IHME forecasts