A number of female patients have approached me over the years with the same general observation -- or complaint.“My husband can fall asleep and stay asleep, or wake up and fall back asleep, while I am struggling to just get a few hours of sleep. Nothing seems to keep him from sleeping”
The truth is that insomnia can affect men and women, but women are much more likely to experience disturbed sleep. Women also tend to feel more comfortable raising health issues, especially sleep issues, with their doctors. But what exactly is going on?? A study approved for publication in the Proceedings of the National Academy of Sciences in June 2016 explains why sleep issues are indeed more common among women.
Recent research has made it clear that a good night’s sleep is as important to our health as diet and exercise habits. We know that poor sleep is associated with a risk of developing obesity and it also heightens general inflammation in the body, a risk factor for many chronic diseases, including heart disease. Adults generally need around seven to eight hours of sleep nightly. Too much sleep and too little sleep are both associated with increased mortality. A sleep poll conducted by the National Sleep Foundation in 1998 found that the average woman aged 30 to 60 years of age slept for only 6 hours and 41 minutes during the average work week.
In 2011, the Wall Street Journal published an article titled “A Sleep Battle of the Sexes “and it opened with this: “He sleeps. She sleeps. They both sleep differently.” Though the article highlighted the sleep problems that women face, it did offer a positive note — that sleep differences may also contribute to explain why women live longer than men.
A more recent 2005 Sleep in America poll of all adults found that women are more likely to have trouble falling asleep and staying asleep, and experience more daytime sleepiness than men. Daytime sleepiness can lead to more accidents and concentration problems and can impair performance at work.
Women do have certain unique biological conditions like the menstrual cycle, pregnancy, and menopause, all of which can affect sleep duration and quality. Varying levels of estrogen and progesterone impact sleep and body temperature. It’s also fair to say that many women struggle to schedule the necessary hours of sleep, as they tend to have “so much on their plate" each and every day.
In the mentioned June 2016 study, the researchers' aim was to compare how the body’s natural clock, or circadian rhythm, affects sleep and alertness in men and women. Fifteen men and 11 women participated in the study, which focused on ultradian sleep-wake (USW) cycle, which is a cycle that lasts for less than 24 hours. Circadian rhythms, on the other hand, last for roughly 24 hours. Ultradian rhythms affect heart rate, breathing, and sleep patterns.
A man’s circadian rhythm lasts on average six minutes longer than a woman’s (24 hours, 11 minutes versus 24 hours 5 minutes).
The researchers studied the women at two points during the menstrual cycle. The subjects were all observed over a period of 36 cycles, which included 60-minute wake periods alternated with 60-minute nap “opportunities.” The observation periods charted core body temperature (CBT), levels of salivary melatonin, alertness, and sleep.
Results of the study showed that women are ready for sleep at a later stage in their circadian rhythm cycle when compared to men. This may also explain why women seem to be more susceptible to sleep disturbances compared to men. Women’s body clocks also seem to instigate earlier wake up times in the morning compared to men. This also explains why they generally feel sleepier in the morning.
Researchers found that women also were less alert at night, which suggests that night shift work might be better suited to men.
So it’s not your imagination. If you’re a woman, you may not be getting enough shut-eye. You may struggle to fall asleep and wake up too early. You do get more deep sleep time than your male counterpart, though, which may help you to cope better with sleep deprivation.
So what do I recommend to help women get the best sleep possible?** 1.** Try to regularize and stay committed to your wake-sleep schedule. You can estimate it by keeping a log for two weeks.
2. Try to make the wake-sleep cycle more reliable by avoiding things that would interfere with your natural schedule like taking naps in the daytime, or drinking excess caffeine.
3. Noting your current prevailing sleep time (not the actual “go to bed” time), you can estimate that two hours earlier is the time for the early melatonin rise. If you want to advance the time of your sleep time (make it later), take a melatonin supplement (dose between 3-5 mg) two hours before the desired time to sleep. Melatonin doesn’t help if you take it right before sleep, but rather earlier in the evening, when levels are low.
4. Exercise in the morning, when resting metabolic rate is higher, and not in the evening.
5. Always consult with your doctor to rule out any other issues that may be causing or contributing to sleep disruption. That can include thyroid disease, leg movement disorder, or a sleep-related breathing disorder. These issues need to be addressed separately.
6. Seek help from your gynecologist if menopausal symptoms are big sleep disruptors.
Eli Hendel, M.D. is a board-certified Internist and pulmonary specialist with board certification in Sleep Medicine. He is an Assistant Clinical Professor of Medicine at Keck-University of Southern California School of Medicine, and Qualified Medical Examiner for the State of California Department of Industrial Relations. His areas of expertise in private practice include asthma, COPD, sleep disorders, obstructive sleep apnea, and occupational lung diseases.