Research has conclusively demonstrated that sleep is essential for human health. It allows the brain and body to rest and recover, enabling better physical, mental, and emotional well-being.
While sleep is necessary for everyone, there are important differences in sleep for men and women. Historically, sleep research has focused disproportionately on males, leaving gaps in knowledge about sleep differences between sexes.
In recent years, though, sleep science has worked to broaden its understanding of both gender- and sex-based differences in sleep. Studies have cast light on how sleep disorders affect each group in distinct ways and how the quantity and quality of sleep diverge between women and men.
In general, women and men have the same nightly sleep needs. The National Sleep Foundation recommends that healthy adults of any gender get between seven and nine hours of sleep per night. Teens and younger children need more sleep.
Growing evidence indicates that, on average, women in the United States get more total sleep each day than men when counting nightly sleep and daytime naps. In one large study, the average time difference depended on age and ranged from five to 28 minutes.
At the same time, women experience more sleep fragmentation and lower quality sleep. Some researchers believe that many women have increased sleep quantity as an attempt to compensate for reduced sleep quality.
It’s important to remember that sleep can vary considerably from person to person and is influenced by a wide range of factors. Studies showing differences in sleep quantity or quality reflect an aggregate; they don’t mean that all women sleep more or have lower-quality sleep than men.
Sex-based factors relate to underlying biologies including hormone production, sleep cycles, and circadian rhythm. Gender-based factors are connected to social and cultural disparities. These factors may be overlapping and multifaceted, creating a complex set of circumstances that affect individual men and women in unique ways.
Sex-based sleep differences generally begin during puberty when young women start their menstrual cycle, which involves significant changes in hormone production. Sex-based factors evolve over time as both men and women undergo biological changes with aging.
Because they reflect broad social and cultural patterns and norms, gender-based factors may start at an earlier age. Like sex-based factors, they can change over time, exerting dynamic influences on sleep.
One reason why women and men don’t sleep the same is that there are differences in their sleep cycles.
During a normal night of sleep, it’s normal to progress through three to five sleep cycles. These cycles last from 70 to 120 minutes and are made up of distinct sleep stages. There are four sleep stages; one is rapid eye movement (REM) sleep and three are non-REM (NREM).
The first three stages are NREM, and the final stage is REM. The first two NREM stages are lighter sleep while stage 3, known as deep sleep, involves substantial slowing of breathing as well as brain and muscle activity. REM sleep in stage 4 is marked by heightened brain activity and more vivid dreaming.
Each sleep stage contributes to the restorative power of sleep, and how a person moves through sleep cycles is known as sleep architecture.
Women and men have variations in sleep architecture. Women accumulate more time in deep sleep (stage 3) and spend less time in stage 1, which is the lightest sleep. Some evidence indicates that this divergence typically begins between the ages of 30 and 40.
Though relatively small, differences in circadian rhythm between men and women can affect the quantity and quality of their sleep.
Circadian rhythm is the body’s 24-hour internal clock. This clock helps regulate all types of bodily systems and processes, including sleep, by coordinating their function at specific times of the day.
A healthy circadian rhythm promotes a steady sleep routine, helping us feel awake during daylight hours and sleepy at night. When a person’s actual sleep schedule isn’t synchronized with their circadian rhythm, it can cause sleep disruptions, daytime sleepiness, and other health problems.
Studies have found differences in circadian rhythms for men and women. While most circadian rhythms aren’t exactly 24 hours long, womens’ internal clocks are typically a few minutes shorter. Women often have earlier circadian timing, meaning a tendency to both go to bed and wake up earlier.
Hormones are a major driver of sleep differences between men and women. Shifts in hormone production during various points in a women’s life can create significant sleeping problems:
Age-related hormonal shifts also affect men and may impact their sleep. In older men, growth hormone production decreases while levels of cortisol, a hormone related to stress, tend to increase. Changing levels of these hormones can occur because of poor sleep, but they may also contribute to increased awakenings and reduced sleep quality.
Aging in men can involve decreasing levels of available testosterone. Some studies have found lower testosterone to be associated with worse sleep and greater problems with obstructive sleep apnea (OSA), a breathing disorder. Evidence suggests that there is a complex relationship involving obesity, sleep, and male hormones, but further research is needed to clarify the connection between testosterone and sleep.
Sleep can be disrupted by underlying health problems, many of which do not affect men and women equally.
Men have higher rates of cardiovascular disease and chronic lung problems, both of which can negatively affect sleep. Excess alcohol consumption is more common in men , and alcohol can interfere with sleep architecture and reduce sleep quality.
Women are more likely than men to be diagnosed with depression and anxiety, mental health conditions that often contribute to difficulty falling asleep or staying asleep. Frequent urination at night, known as nocturia, can hinder sleep and affects more than 75% of women over age 40, often because of a connection to higher rates of incontinence and overactive bladder in women. Women are more likely to experience heartburn and acid reflux, which can worsen overall sleep.
Gender-based influences on sleep are closely intertwined with social and cultural norms that have unequal impacts on women and men. Because these norms are complex, they may implicate sleep in multifaceted ways that are not the same for all individuals.
Caregiving is a prime example of a gender-based factor that affects sleep. Women disproportionately serve as informal caregivers for older adults, young children, or ill family members. Caregivers experience more sleep interruptions as well as heightened overall stress that can worsen sleep.
Gender norms play a role in employment opportunities, work schedules, and the division of household obligations. In most cases, researchers have found that these norms place additional strain on women, affecting their sleep patterns and sleep hygiene. That said, these norms can also affect men. For example, some men may feel heightened cultural pressure to be income-earners, leading to decreased time devoted to sleep.
Numerous sleep disorders, including insomnia, sleep apnea, and restless leg syndrome (RLS), affect women and men at different rates.
Women are significantly more likely than men to be diagnosed with insomnia. In total, their lifetime risk for insomnia is 40% higher. The higher rate of insomnia in women is believed to be tied to both gender- and sex-based factors.
In addition to a greater likelihood of having insomnia, women commonly have more complex insomnia that involves multiple symptoms while men typically report only one insomnia symptom.
Obstructive sleep apnea, a dangerous condition of lapsed breathing during sleep, is considerably more common in men. Moderate to severe OSA is estimated to affect 13% of men and 6% of women between ages 30 and 70. OSA provokes consistent sleep interruptions and is associated with heart problems, depression, and other health issues.
Part of the divergence in the prevalence of OSA in men and women is believed to be related to how doctors diagnose the condition. Women’s symptoms are often interpreted differently resulting in fewer referrals to specialty sleep clinics where OSA is normally diagnosed.
Restless leg syndrome, which involves a powerful urge to move the limbs, is a sleep disorder that is more common in women. It happens more often during pregnancy, which is the main reason for its increased prevalence in women.
Sleep deprivation takes a physical and mental toll. The consequences of insufficient sleep for men and women are similar and reflect only minor differences.
In the National Sleep Foundation’s 2007 Sleep In America Poll, around 80% of women said they just accept it and power through when they are sleepy during the day. At the same time, some evidence indicates that women rapidly develop a “sleep debt” more rapidly after a period of poor sleep.
Both men and women can suffer serious negative effects if their circadian rhythm is not synchronized with daylight and nighttime. However, differences in circadian timing between men and women may make women more susceptible to the effects of jet lag or shift work. This may explain studies that have found an elevated risk of workplace accidents among women working night shifts.
Sleep studies have traditionally focused on individuals, but in everyday life, many adults sleep with a partner. Whether their partner is a man or a woman, this sleeping arrangement can affect nightly rest.
When sleep is analyzed objectively, studies have generally found that people sleep better alone than with a partner. But when surveyed, most people say that their sleep is subjectively improved when they are next to their partner. For heterosexual or same-sex couples, sharing the bed with a partner can communicate a sense of calm and safety that is conducive to sleep.
Of course, not all relationships promote quality sleep. For married couples, research has found that positive relationship characteristics are associated with better sleep, and negative characteristics are tied to poorer sleep. In older adults who often face sleep problems tied to aging, marriages with high levels of mutual support appear to enhance both partners’ sleep.
Sharing a bed can raise sleep challenges for men and women. Men are more likely to snore, so their bed partners may be more inclined to have their sleep interrupted. Differences in circadian rhythm and sleep schedules between bed partners may generate additional sleep disruptions. Not surprisingly, the impact of these factors can vary markedly for any given couple based on their specific circumstances.