Coffee won’t keep you up. But these other vices might.

Shutterstock

Drink that latte, cappuccino, or straight black long into the night. It’s not going to affect the quality of your sleep, a new study has found.

Research led by Florida Atlantic University observed 785 African-Americans for a total of 5,164 days and nights, while recording how much caffeine, alcohol, and nicotine they consumed.

Drinking coffee within four hours before bedtime was not found to affect sleep quality, concluded the study, the results of which were published in the journal Sleep. However, researchers said that people should still be mindful of how much coffee they drink and be aware of individual sensitivities to caffeine, which do exist.

If you stay out drinking with friends, however – or happen to enjoy a before-bed cigarette (and any other form of consuming nicotine) – those are two things that will definitely affect your sleep.

The study found that using nicotine or alcohol within four hours of going to sleep created worse sleep continuity. Nicotine was particularly linked with sleep disturbance, and its effects are worse if you have insomnia – nightly nicotine use in any form meant an average 42-minute reduction in sleep duration.

So instead of a moody nightly cigarettes, or relaxing late-night glass of wine, just try a warm cappuccino or a coffee drink in any form.

The study’s lead author said the research was especially important for African-Americans, whom it studied exclusively.

“African Americans have been underrepresented in studies examining the associations of nicotine, alcohol, and caffeine use on sleep,” Christine E. Spadola, PhD, lead author of the study and an assistant professor in FAU’s Phyllis and Harvey Sandler School of Social Work, said in a release.

“This is especially significant because African Americans are more likely to experience short sleep duration and fragmented sleep compared to non-Hispanic whites as well as more deleterious health consequences associated with inadequate sleep than other racial or ethnic groups.”