Multiple studies suggest a variety of benefits are associated with hitting the sleep "sweet spot," but how long is just right for most people? Writing for the New York Times, Jane Brody shares the sleep target people should aim for—and offers six expert tips to get a better night's sleep.
Sleep deprivation has negative mental and physical effects
Millions of Americans have trouble falling or staying asleep, Brody reports. In fact, a CDC survey found that more than one-in-three American adults said they are unable to consistently get a good night's sleep.
Moreover, even individuals who previously reported being "good" sleepers said they experienced sleep issues during the Covid-19 pandemic—often as a result of pandemic-related anxiety, longer remote work hours, or grief from the loss of a loved one, Brody writes.
A 2019 study conducted by researchers at Northwestern Medicine and Rice University discovered that spouses who were grieving the loss of a loved one and sleeping poorly had higher levels of chronic, body-wide inflammation and an increased chance of getting heart disease and cancer.
According to Brody, consistent sleep deprivation can result in significant damage to an individual's physical and mental health. For instance, it can increase the risk of heart disease, high blood pressure, stroke, and Type 2 diabetes. In addition, it can cause brain fog, low energy levels, increased irritability, and decreased sex drive.
In another study published last spring in Nature Communications, researchers tracked almost 8,000 50-year-olds in Britain for around 25 years. When they compared the participants who slept around seven hours each night with the participants who averaged six hours of sleep or less, those who slept six hours or less a night were 30% more likely to have received a dementia diagnosis almost 30 years later.
How many hours should you sleep each night?
Several studies suggest that the "sweet spot" for optimal health lies somewhere between six and eight hours of sleep each night.
In a six-year study of more than one million adults ages 30 to 102, researchers at the University of California, San Diego, and the American Cancer Society found that the highest mortality rates were among participants who slept more than eight hours or less than four hours a night.
In addition, the Nurses' Health Study followed 71,617 women for a decade and found that participants who slept eight hours a night had the lowest risk of developing heart disease.
However, another study following 84,794 nurses for up to 24 years found that participants who slept nine or more hours each night doubled their chance of developing Parkinson's disease compared to those who averaged six hours or less.
Brody also noted that sleep amount can affect appetite-regulating hormones, and those who sleep less tend to weigh more than those who sleep for longer periods.
6 tips for a better night's sleep
Brody suggested following these six tips from experts for better sleep:
- Eat and drink cautiously close to bedtime. Brody warned against consuming caffeine in the late afternoon or evening, and recommended avoiding large, heavy meals close to bedtime.
- Practice good sleep hygiene. Brody recommended going to sleep and waking up around the same time each day.
- Do not use alcohol to help you unwind. Instead, Brody suggested taking a warm bath or meditating.
- Avoid sleep-inhibiting light. Brody encouraged reading before bed—but not if it is on a computer or tablet that emits sleep-inhibiting light.
- Mitigate sleep disturbances. If outside light impacts sleep, Brody suggested installing light-blocking shades or curtains or using a sleep mask. For noise issues, she suggested using earplugs or a white-noise machine.
- Consider cognitive behavioral therapy. According to Brody, this therapy can challenge underlying thoughts and behaviors that may be causing sleep deprivation. (Brody, New York Times, 12/6)