Caffeine in sugary drinks and sleep quality in young women
What it found
Young women who drank energy drinks or sweet coffee drinks reported worse sleep than those who did not.
This was measured in 462 women around age 23.
What they found
Studies in people
Energy drinks and sleep
Women who said they drank any energy drinks had worse sleep scores than those who drank none. Their scores were about 0.84 points higher on a scale where higher means poorer sleep.
Sweet coffee drinks
Drinking one or more high-calorie coffee drinks a day was linked to sleep scores 1.00 point higher than drinking none. These women also took about 8.7 minutes longer to fall asleep on average.
Sugary sodas and sports drinks
Before adjusting for other factors, women with poor sleep were more likely to drink sugary beverages daily. After accounting for income, education, and weight, this link was no longer clear.
Fruit, vegetables, and breakfast
Eating fruit, vegetables, or breakfast regularly was not linked to better or worse sleep scores once other factors were taken into account.
What the authors conclude
- They note that poor sleep was very common among these young women, with 45% reporting it.
- They suggest that young women who sleep poorly should look at whether sugary caffeinated drinks might be playing a role.
- The authors add that the link could go both ways, meaning poor sleep might lead women to drink more caffeine, which then worsens sleep further.
How it was done
Scientists know that poor sleep is common in young adults, but few studies have looked at how diet links to sleep quality in this group. The authors wanted to see if certain eating and drinking habits matched up with poor sleep in young women.
They surveyed 462 women, average age about 23, asking what they ate and drank over the previous 7 days. The women also filled out a questionnaire rating their own sleep quality over the past month. The researchers then compared the answers.
What it can’t tell you
- Because everyone was asked about their diet and sleep at the same time, this cannot show whether the drinks caused the poor sleep or the poor sleep led to more drinking.
- All information came from questionnaires rather than sleep trackers, so people may have misremembered what they consumed or how well they slept.
- Only women were included, so the results may not apply to men.
Who paid
- Funding
- Funded by NHLBI NIH HHS (from the PubMed record).
- Authors work at
- University of Arizona College of Medicine, USA
The paper
- Title
- Dietary behaviors and poor sleep quality among young adult women: watch that sugary caffeine!
- Type
- Study
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Young DR, Sidell MA, Grandner MA, Koebnick C, Troxel W (2020). Dietary behaviors and poor sleep quality among young adult women: watch that sugary caffeine!. Sleep health. doi:10.1016/j.sleh.2019.12.006Free full textPubMed 31932239DOI
Summary written 30 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error