If you’re reading this, there’s a good chance you managed to get some sleep last night. However, the real question is whether you feel rested. Experts emphasize that evaluating how rested you feel is just as important as the number of hours you spend sleeping.
People typically spend about a third of their lives asleep, but the recommended duration varies. While eight hours is often cited as the ideal amount, individual needs differ, and sleep requirements change over time. Babies and young children generally need more sleep, while those over 65 can often function with slightly less than the recommended seven to nine hours.
Experts in sleep science and medicine offer insights into how much rest people truly need and whether factors such as gender play a role in sleep duration and quality.
One key point emphasized by researchers is that sleep quality matters more than sheer quantity. Despite its crucial role in overall health, sleep remains a somewhat mysterious biological function. “The reasons aren’t entirely clear, but it’s an essential thing that we all do,” explained Dr. Rafael Pelayo, a sleep specialist at Stanford University. “Something remarkable happens when you sleep. It’s the most natural form of self-care that we have.”
According to Molly Atwood, a behavioral sleep medicine clinician at Johns Hopkins, most people sleep between seven and nine hours per night, a range associated with the lowest risk of health problems. However, health risks increase for those who sleep less than six hours or more than nine hours regularly. Atwood noted that individual variations exist, so some people may function well with slightly less or more sleep than the average recommendation.
Rather than focusing solely on the number of hours slept, Pelayo emphasized the importance of waking up feeling refreshed. “What you really want to do is wake up feeling refreshed—that’s what it’s about,” he said. He likened poor-quality sleep to leaving a favorite restaurant still feeling hungry. “If somebody tells me that they sleep many hours but they wake up tired, something is wrong,” he added.
Sleep requirements fluctuate over the course of a lifetime. Newborns require the most sleep, typically between 14 to 17 hours daily. “Definitely when we’re babies and children, because we are growing so rapidly, we do need a lot more sleep,” Atwood explained.
The National Sleep Foundation provides general recommendations based on age. For adults aged 26 to 64, the ideal sleep duration is between seven and nine hours. Those aged 65 and older may need slightly less, whereas young adults aged 16 to 25 may benefit from slightly more sleep.
Sleep occurs in cycles, with each cycle lasting approximately 90 minutes. These cycles consist of different sleep stages, each serving a distinct purpose. Atwood pointed out that in the early part of the night, people experience more slow-wave sleep, or deep sleep, which plays a critical role in physical restoration and healing. This phase is particularly significant because it is when growth hormones are released.
In contrast, during the latter portion of the night, people spend more time in rapid eye movement (REM) sleep, commonly referred to as dream sleep. This stage is essential for cognitive functions such as learning and memory consolidation, the process through which short-term memories are converted into long-term memories.
Children experience significantly more deep sleep than adults. Atwood stated that around 50% of their sleep falls into this category. However, as individuals reach adolescence, the proportion of deep sleep decreases since the body no longer requires as much repair and restoration.
Interestingly, differences in sleep patterns between genders begin to emerge around puberty.
Although research does not confirm that women require more sleep than men, Atwood noted that women tend to sleep slightly more than men on average. This discrepancy begins early in life. Pelayo observed that teenage girls, despite having the same sleep needs as their male counterparts, often sleep less and report more frequent instances of insomnia.
Motherhood significantly affects women’s sleep patterns, particularly when caring for newborns. First-time mothers often experience frequent nighttime awakenings to tend to their infants, resulting in less sleep overall. Allison Harvey, a clinical psychologist and professor at UC Berkeley who specializes in sleep research, noted that this disrupted sleep can have lasting effects.
Hormonal fluctuations also contribute to variations in women’s sleep quality and quantity. Pregnancy and menopause, in particular, can significantly impact sleep. “With menopause in particular, women can develop deterioration in their sleep with an increased number and duration of nighttime awakenings,” explained Dr. Mithri Junna, a Mayo Clinic neurologist specializing in sleep disorders.
Atwood added that hormonal shifts throughout the menstrual cycle can also influence sleep duration. “Women may also need more sleep right before their menstrual cycle,” she said. She emphasized the importance of paying attention to the body’s natural signals. “There are definitely times that your body’s telling you that you need more sleep,” Atwood said. “It’s important to listen.”
Lack of sufficient sleep can manifest in several ways, including irritability, mood swings, and difficulty concentrating. While these may seem like minor inconveniences, chronic sleep deprivation can lead to more severe health consequences.
“If you’re not getting enough sleep or you have untreated insomnia or sleep apnea, your risk of depression increases,” Atwood warned. Additionally, insufficient sleep raises the likelihood of cardiovascular issues such as high blood pressure, heart attacks, and strokes. Sleep deprivation also weakens the immune system and has been linked to an increased risk of developing Alzheimer’s disease.
People who consistently wake up feeling fatigued despite sleeping the recommended number of hours may want to consult a doctor. A primary care physician can assess whether underlying medical conditions might be contributing to poor sleep quality. If sleep problems persist, consulting a sleep specialist could be beneficial in identifying and addressing the root causes of sleep disturbances.
Ultimately, ensuring both sufficient sleep quantity and high-quality sleep is crucial for overall health and well-being. Experts agree that listening to the body’s natural cues, maintaining a consistent sleep schedule, and addressing any persistent sleep problems can lead to significant improvements in physical and mental health.