One of the things that excites us about working at Jawbone is not just the ability to ask questions about biology, health and anthropology, but also the capacity to peek into the data for the answers. This is one of those moments where we found an unexpected insight into how people really live.
The Truth About Men and Women
Despite conventional wisdom, societal stereotypes, and in the case of one author, personal observation of family members, the truth of the matter is that women sleep more than men. A lot more. 20 minutes more. Over the course of a year, that equates to women sleeping an additional 5 full days.
And this happens in just about every country, and at almost every age, especially before retirement. While there are staggering differences in sleep duration by country (Japan averages 6.1 hours of sleep compared to Australia’s 7.25 hours of sleep), women still tend to sleep more than men.
Sleep As We Age
We also observe differences in how we sleep as we age. Teens need the most sleep — 8 to 10 hours to function best — according to the National Sleep Foundation. In the US and western countries, teens get the most sleep on average, although far less than the NSF recommends. In eastern countries like Japan and China, this trend is reversed, perhaps an indication of how stressful secondary school is in these countries. Generally, we get the least amount of sleep when we’re middle aged, caring for our families and careers. As we get older and retire, the gap between men and women gradually disappears and the amount of sleep we get begins to rise. The age at which this happens varies by country: in the US, it’s around 65, in Japan, 55, in China, at 60.
Why Do Women Sleep More?
What is the impact of all of the sleep-reducing issues that tend to affect women’s sleep? What, if any impact is there from pregnancy, nursing, menopause, the traditional role of taking care of the family? How about all the complaints of snoring partners?
Or perhaps the better question is, what are men doing wrong that prevent them from getting more sleep?
While there may exist societal reasons that women tend to sleep more than men, such as differences in stereotypical work schedules, there are likely biological reasons as well. Some research has explored the possibility that women need more sleep for the sake of recuperation before and after childbirth. Of course there is a big difference between needing more sleep and successfully getting more sleep. 
One possible explanation is that men may have more disrupted sleep due to conditions like sleep apnea, a breathing disorder that tends to be correlated with higher Body Mass Index. According to the Centers for Disease Control, the average 30 to 39 year old male is has a BMI of 29, just one point below the medical definition of obese.  The National Sleep Foundation estimates that 18M Americans likely have sleep apnea, the majority being male. 
Frankly, we don’t know exactly why women sleep more than men. But we would love to hear your theories. Please share your thoughts with us on Twitter, Instagram, Facebook, or by email. We will compile them and see if we can address them in a coming blog post.
Technical Notes: This study was based on millions of UP wearers who have regularly used UP by Jawbone over the past 2 years to track their sleep. The European Union data consists of UP wearers who reside in one of the five most populous EU countries: France, Germany, Italy, Spain, or the United Kingdom. All data is anonymized and presented in aggregate.
 : Teens and Sleep National Sleep Foundation.
 : Horne, Jim. Do Women Need More Sleep Than Men? National Sleep Foundation.
 : This is the Average Man’s Body. The Atlantic.
 : Sleep Apnea National Sleep Foundation.