How did the invention of canning food affect life expectancy?

Before the invention of canning, food preservation methods were limited. People relied on salting, smoking, drying, and fermentation to preserve food, but these methods were not always effective in preventing spoilage. As a result, foodborne illnesses were common and often fatal.

The invention of canning in the early 19th century revolutionized food preservation. Canning involves sealing food in airtight containers and then heating it to a high temperature to kill harmful bacteria. This process creates a vacuum that prevents oxygen from reaching the food, which inhibits the growth of bacteria and other microorganisms.

Canned food is shelf-stable, meaning it can be stored at room temperature for long periods without spoiling. This made it possible to transport food over long distances and store it for future use, which improved access to nutritious food and reduced the risk of foodborne illnesses.

As a result of these factors, the invention of canning food contributed to a significant increase in life expectancy during the 19th and 20th centuries.