Americans today live approximately twice as long on average compared to the era when the Declaration of Independence was signed.
Historians estimate that at the nation's inception in 1776, the average life expectancy ranged from about 35 to 40 years. However, individuals who survived the perilous early years of childhood in colonial America often reached their 60s or even 70s.
Presently, data from the Centers for Disease Control and Prevention (CDC) indicates the average lifespan is around 79 years.
This substantial increase in longevity over centuries is primarily attributed to a significant decrease in infant mortality and deaths caused by infectious diseases, as noted by numerous researchers. Crucial advancements in sanitation, access to clean water, improved nutrition, widespread vaccination, and sophisticated medical care have all contributed to lower mortality rates.
Childbirth was dangerous, and without antibiotics and vaccines, many infectious diseases, such as measles, smallpox and pneumonia, were deadly. Now we have cleaner water and sanitation, vaccines and antibiotics that have significantly prolonged life.
A Harvard-trained physician also highlighted that progress in treating chronic conditions such as high blood pressure, cancer, and diabetes has considerably extended lives. The CDC further confirms that enhanced prevention and treatment of high blood pressure have been instrumental in reducing fatalities from heart disease and stroke, which are among the leading causes of death in the country.
Transformative Public Health Initiatives
Dr. Mia Kazanjian, a Stanford-trained body and breast radiologist based in Greenwich, Connecticut, with a focus on longevity, points to suboptimal sanitation, inadequate hygiene practices, and limited medical interventions as reasons for the shorter life expectancies in the 1700s.
Maternal mortality has also seen a dramatic decline over the last century, thanks to innovations in antibiotics, blood transfusions, and safer obstetric practices, according to the CDC.
Dr. Kazanjian identified several pivotal advancements throughout history that have bolstered longevity, including the establishment of early municipal water systems that supplied safer drinking sources.
Sewer system networks were built, the first in Brooklyn in 1857. These allowed people to drink clean water and dispose of waste. Indoor plumbing with toilets and bathrooms became more widespread.
During this period, public understanding of disease improved, leading to the development of public health measures aimed at minimizing risks. The late 1800s saw the widespread acceptance of germ theory in medicine and public health, which significantly influenced the Sanitary Era, as explained by Dr. Kazanjian.
The Federal Quarantine Act of 1878 allowed the government to prevent spread of infection from out of the country, from epidemics like yellow fever. Food safety regulations went into effect in 1906, when the Pure Food and Drug Act and Federal Meat Inspection Act were passed.
By 1900, the National Vital Statistics Report indicated that the average life expectancy had risen to approximately 49 years.
Medical Breakthroughs and Lifestyle Changes
Another monumental stride in extending lifespans came with the creation of vaccines and antibiotics for preventing and treating illnesses, Dr. Kazanjian stated.
Jenner developed the smallpox vaccine in 1796, Pasteur created vaccines for rabies and anthrax in the 1880s, and several scientists created vaccines for polio, measles, influenza, mumps and rubella in the mid 1900s. Antibiotics proliferated in the 1940s, specifically penicillin and tetracycline. By 1950, the US life expectancy was about 68 years old.
From the mid-20th century until 2014, life expectancy continued its upward trajectory, primarily due to
