A Great Depression II will tend to do that.
During the Great Depression, life expectancy increased. Some of it might have just been a previous trend that continued, but other factors such as less smoking, fewer rich diets and heart attacks, etc. are believed to be a factor.
The only cause of death that increased was suicides. Although Alcoholism also increased, and I suppose the resulting shortened lives weren’t counted until later.
https://www.pnas.org/content/106/41/17290.full