Facing more than $50,000 in student debt, Michael Gary dropped out of college and took a truck driving job in 2012. It paid the bills, he said, and he could reduce his expenses if he lived mostly out of a truck.

But over the years, the job strained his relationships. He was away from home for weeks at a time and could not prioritize his health: It took more than three years to schedule an optometry appointment, which he kept canceling because of his irregular work hours. He quit on Oct. 6…

Truck drivers have been in short supply for years, but a wave of retirements combined with those simply quitting for less stressful jobs is exacerbating the supply chain crisis in the United States, leading to empty store shelves, panicked holiday shoppers and congestion at ports. Warehouses around the country are overflowing with products, and delivery times have stretched to months from days or weeks for many goods.

A report released last month by the American Trucking Associations estimated that the industry is short 80,000 drivers, a record number, and one the association said could double by 2030 as more retire.