Life expectancy is defined as the average number of years a person is expected to live given a certain age.
Factors impact an individual’s life expectancy includes war, disease, genetics, diet, lifestyle, gender, and health. Additional factors like crime, environmental toxins, the availability of safe and affordable housing, and income status also impact people’s ability to live long, healthy lives.
The line graph above displays the trend of life expectancy from 1900 to 2017.
Over the past century, population health in the United States has improved dramatically. At the beginning of 1900, a person born in the United States was expected to live 47.3 years, compared with 78.6 years in 2017.
Before 1945 changes in life expectancy were very volatile. They go up and down by one or two years of life expectancy from year to year. This volatility is most likely due to outbreaks of various infectious diseases, war, and Great Gepression.
The great spike from 1914 to 1918: Life expectancy went down by about 28%, as a result of World War I and the 1918 Spanish flu claiming 117,465 and about 675,000 American lives, respectively. In the late 1920s and throughout the 1930s, premature death was a major factor. The Great Depression wreaked havoc on all genders and races from 1929 through 1939. Sadly, suicide mortality peaked with unemployment in the most recessionary years: 1921, 1932, and 1938.
After World War II, mass vaccination and expanded health care probably accounts for how steady the trend becomes. The jump in life expectancy in 1950 was due in part to advancements in medicine, such as the development of the external pacemaker in 1952 and the first successful open-heart surgery in 1953.
The past few decades have seen a plateauing of life expectancy of Americans along with a rise in deaths due to various causes—including Alzheimer, Parkinson and hypertension and, more recently, suicide, alcoholism and drug overdose.
And a new cause has emerged: As per the National Center for Health Statistics (NCHS) of the Centers for Disease Control and Prevention (CDC), the COVID-19 pandemic has contributed to the decrease in life expectancy by 1.5 years. How lasting are the effects of COVID-19 on U.S. life expectancy remains to be seen in the coming years.