Weight gain in teens may be linked to late nights, says study

US research reveals teenagers’ body mass index increasing with every hour they stay up during the school week

Staying up late could be associated with weight gain in teenagers, according to a study. Researchers in the US found that each additional hour adolescents stayed up during the school week has been associated with an increase of 2.1 points in body mass index.

The authors of the paper, published in the Sleep journal on Friday, suggest that the results – observed in a sample of more than 3,000 participants – highlight that bedtimes could have a role to play in weight management.