Moonlighting — holding down a second job — is not something most people want to do. They have to do it to make ends meet because they’re not paid enough. So which occupations pay so poorly as to generate the most moonlighters?

According to Pew Research Center data, they include the jobs society claims to value most in part because they are dedicated to helping others: the people who save our lives in emergencies, who teach our children, who even birth our children.

These are also jobs where sleepiness is hazardous.

Pew analyzed data from the Bureau of Labor Statistics on workers who have more than one job. Although the percentage of U.S. job holders has generally decreased since the late 1990s, it found there are occupations that somehow generate multiple jobs at a much higher rate than the average American. Here’s the list: