A new study to be published in the August issue of the journal SLEEP suggests people who don't get enough shuteye won't get the full benefit of vaccines that fend off illness.
The study was led by University of California's Aric Prather while he was a doctoral student in Pennsylvania.
It examined 125 people between the ages of 40-to-60.
Each participant was administered the standard, three-dose hepatitis B vaccine.
Researchers found that those who slept less than six hours on average per night were less likely to build antibody responses to the vaccine.
And they were 11-point-five times more likely to be unprotected by the vaccine.
Those who got more than seven hours of sleep on average had a better response.
Sleep quality didn't affect the findings.
The National Sleep Foundation recommends a person get seven to nine hours of sleep a night.
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