Alcohol and resting heart rate: what 20,968 wearables showed
A study of 20,968 people compared nights with more and fewer drinks than each person's usual. What it found, and what it cannot say about your nights.
By Lomba 5 min read
In March 2026 a study in PLOS Digital Health looked at the night that follows a drink. It used up to a year of data from 20,968 people wearing a WHOOP strap, more than five million days in all, with each person's own morning note of whether and how much they drank.
Here is what it found, what it says it cannot tell you, and the one idea we think matters most.
What the study did
- Who
- 20,968 adults, 10,025 women and 10,943 men, who started wearing a WHOOP in 2023. Each had at least 84 nights of data and at least one entry in the app's alcohol journal.
- What was compared
- Each person against their own usual. The headline figures set a night with one drink more than that person's average against a night with one fewer.
- What was measured
- Resting heart rate and heart rate variability during sleep, sleep time, and activity the next day.
- Who paid
- WHOOP funded the study, and seven of its eleven authors work there. The paper says so and asks readers to keep it in mind.
Four takeaways
The night shows it.
A night with one drink more than usual, against one with one fewer, went with a resting heart rate 2.8 beats per minute higher in women and 2.4 higher in men. Heart rate variability was 3.8 and 3.3 milliseconds lower.
More drinks, a bigger gap.
Each further two drinks went with about as much again in resting heart rate, and with a larger drop in variability. Sleep was shorter too, by 7 to 8 minutes at the first step and by 13 to 19 minutes at each of the next two. An earlier study of 4,098 Finnish employees found the same shape: heart rate in the first hours of sleep was 1.4, 4.0 and 8.7 beats higher after low, moderate and high intake.
Variability differed by age more than heart rate did.
Variability was 5.7 milliseconds lower in people in their twenties and 2.6 lower in those sixty and over. Resting heart rate was 2.2 to 2.7 beats higher in every age group.
It is an average, and the paper says so.
The study does not report how much one person's response differs from another's. In the authors' words, the findings "reflect short-term deviations from an individual's typical physiology and behavior rather than between-person differences or long-term health implications". Drinks were self-reported, late-night eating was not separated out, and the authors say randomized trials would be needed to show cause.
Each row has its own scale, because the three units differ.
In women, the night after one drink more than their usual, against one fewer: resting heart rate 2.8 beats per minute higher, heart rate variability 3.8 milliseconds lower and sleep time 8.4 minutes shorter.
Each step up in intake went with a larger gap: 1.4, 4.0 and 8.7 beats per minute above the same person’s nights without alcohol.
The main takeaway
Twenty thousand people give a reliable average. They do not give your number.
The study describes the typical night after a drink. How your own nights respond is a separate question, and only your own record can answer it.
What Lomba does with that
Lomba keeps the two kinds of morning apart and shows them side by side: the mornings after a drink and the mornings without one, each with its average and the count of days behind it.
A gap can come from one odd stretch, a holiday or a run of late nights. So Lomba measures it again before it calls anything a pattern: inside the same weeks, with the morning before counted, and in each half of the record. How it works follows two examples through those checks.
It has limits, and we would rather say them:
- It takes time. A comparison needs enough mornings on both sides. Until then Lomba says it is still collecting, and shows no gap.
- Not a cause. Evenings with a drink differ in other ways too. What Lomba finds is a pattern in your own days, not proof of cause, and not medical advice.
- No target. Lomba sets no limit and gives no advice about drinking. What a number means for your health is a conversation with your doctor.
Sources
- Grosicki GJ and others. Real-world effects of alcohol on heart rate, sleep, and physical activity by age and sex. PLOS Digital Health, 9 March 2026.
- Pietilä J and others. Acute effect of alcohol intake on cardiovascular autonomic regulation during the first hours of sleep in a large real-world sample of Finnish employees: observational study. JMIR Mental Health, 2018.