A coffee at bed time

A new study of 785 Africa-Americans over the last 14-years has found that drinking coffee close to bedtime does not affect the quality of sleep, but that evening alcohol intake and smoking are the main culprits that disrupt sleep. The research is one of the largest longitudinal studies conducted so far to assess how evening use of the substances affects sleep quality.

The research, which was conducted at Florida Atlantic University and Harvard Medical School, showed that drinking alcohol or taking nicotine within four hours of going to bed was significantly more likely to interfere with sleep than drinking caffeine. African Americans tend to suffer from insomnia, sleep apnea and other sleep-related disorders more than other ethnic or racial groups.

Caffeine intake, on the other hand, seemed to have no such effect.