Living a long, healthy life is a goal for most of us, but it might not be our primary focus every single day. Longevity experts, however, devote a significant portion of their time to just that.
Dr. Gary Small, Chair of Psychiatry at Hackensack University Medical Center
and author of numerous books on ‘aging successfully,’ including The Longevity Bible, describes a longevity expert as “a professional who specializes in fostering healthy aging.”
“As a geriatric psychiatrist, my research and clinical efforts have focused on helping people keep their brains young and cognitive abilities strong, while delaying the onset of Alzheimer’s disease and other forms of dementia,” he says.
I asked Dr. Small exactly how sleep contributes to a long life, the sleep habits he recommends for living longer and why sleep deprivation is the enemy in efforts to age healthily and extend our lives.
How can sleep help you live longer?
Obviously we can’t survive for long without sleep, but there is also evidence that the quality of our sleep can directly impact our lifespan.
Recent research found that those who slept well (which was measured by five factors: sleeping for 7–8 hours a night, having difficulty falling asleep less than twice a week, having trouble staying asleep less than twice a week; waking feeling rested 5 or more days a week, and not using sleep medication) had a greater life expectancy than those who didn’t.
In the case of men, it was 4.7 years higher, and in women it was 2.4 years higher.
During sleep our brains are also washing out toxins
Sleep also has a significant impact on our brains and bodies. Deep sleep, for example, is considered the most restorative stage of sleep, and contributes to cell regeneration, strengthening of the immune system, growth and repair of tissues and bones, energy restoration and learning and memory storage.
“Many of us assume that sleep is only a passive, resting state, but during sleep our brains are also washing out toxins,” says Dr. Small.
He notes that sleep has also been found to influence the build-up of brain amyloid, which is an abnormal protein deposit present in Alzheimer’s disease.
“Lack of sleep or more fragmented sleep may increase the accumulation of amyloid plaques,” says Dr. Small.
He notes a study in which scientists at Johns Hopkins University analyzed Baltimore Longitudinal Study data from 70 older adults without dementia and found that, “subjects who reported less sleep or poorer sleep had higher amyloid levels on their brain scans.”
“Other research points to the possibility that these scans also measure levels of brain inflammation, which is known to contribute to cognitive decline associated with aging,” Dr. Small adds. “A good night’s sleep has been shown to reduce brain inflammation.”
Research also shows that poor sleep is associated with poor mental health, which can negatively impact our lifespan.
“The Epidemiologic Catchment Area study showed that 40 percent of people with insomnia have a psychiatric disorder such as depression or anxiety, compared with only 16 percent of people with normal sleep patterns,” says Dr. Small.
Poor mental health can impact longevity as “untreated or inadequately treated depression shortens life expectancy from suicide and medical illnesses.”
The doctor explains that sleep improves mood and benefits mental performance, and points to research that shows good sleep appears to be linked to better well-being.
“A study from investigators at Pennsylvania State University surveyed more than 4,000 college students and found that restful sleep was associated with the absence of depressive symptoms.”
Sleep habits to help you live longer
If you want to increase your likelihood of living longer, you don’t have to completely overhaul your life in the style of Bryan Johnson.
I asked Dr. Small for sleep habits he recommends to help us live longer, and most of them can be adopted tonight.
“It is possible to sleep well at night without sleep medications by adopting good sleep habits and changing certain behaviors. The following are some strategies that can promote restful sleep,” he says.
1. Keep a consistent sleep schedule and only use your bed for sleep
“Control stimuli and restrict sleep. Set a consistent bedtime and time to wake up [and] avoid naps,” says Dr. Small.
Maintaining consistent sleep and wake times helps to regulate your circadian rhythm, which means producing hormones needed for sleep (like melatonin) and waking up (cortisol) are released when they should be. But this simple habit is also associated with living longer.
Sticking to a sleep schedule could reduce your risk of death by up to around 50%
Among the findings of researchers who, in 2014, looked at “the sleep patterns and biochemical profile of oldest old individuals” was that these older people stuck to strict sleep and wake schedules, indicating a relationship between longevity and a consistent sleep schedule.
A more recent 2024 study found that higher sleep regularity (which they defined as day-to-day consistency of sleep–wake timing) was “associated with a 20%-48% lower risk of all-cause mortality.”
Effectively, sticking to a sleep schedule could reduce your risk of death by up to around 50%.
Dr. Small also advises that alongside a consistent sleep schedule, it’s important to “use the bed only for sleep.”
And, if you’re struggling to drop off, you need to be disciplined with this rule.
“Many insomniacs develop the bad habit of lying in bed while awake, which promotes insomnia symptoms,” he explains.
“Instead, get up and leave the bedroom if you are unable to fall asleep within 20 minutes, and only return to bed when you feel sleepy again.”
2. Stay passively awake if you’re struggling to sleep
One tool for getting better sleep seems counterintuitive at first, but Dr. Small explains that if you struggle to get to sleep or experience insomnia, not trying so hard to drop off might actually help you sleep better.
“Many people with insomnia become anxious about their inability to fall asleep and stay asleep, which serves to keep them awake even longer,” he says. Instead, he had advises “staying passively awake.”
This involves “a paradoxical intention wherein the insomniac avoids any effort to fall asleep,” Dr. Small explains.
The outcome of this is that, “letting go of worries about falling asleep promotes relaxation and makes it easier to sleep.”
3. Improve your sleep environment
“Adjust the details of your immediate sleep environment to make it more comfortable. Keep your bedroom quiet, dark and cool, and make your bedding as cozy and relaxing as possible,” says Dr. Small.
If you’re wondering how cool you need your sleep space to be, research has shown that the optimum temperature for sleep is between 65 to 70 F (18 to 21 °C).
When it comes to the rest of Dr. Small’s advice, our top 8 sleep products for 2025, includes ear plugs and eye masks designed to limit noise and light in the bedroom, and our guide to the best bedding sales will help if you want to upgrade your sleep setup without breaking the bank.
But what you don’t do can be just as important for creating a healthy sleep environment, as Dr. Small advises restricting the activities you carry out in that space.
“Avoid watching television, playing videogames, or using smartphones excessively in the bedroom,” he says.
4. Learn to relax
This tip is likely to benefit you whether you experience a sleep issue like insomnia or nighttime anxiety, or just want to be able to wind down better before bed.
Dr. Small suggests learning to relax before sleep, offering several easy methods to try.
“Mindful meditation, guided imagery, systematic muscle relaxation and other methods can help people to fall asleep,” he says.
“I often recommend that my patients with insomnia download a guided meditation app on their smartphones or tablets and use it to induce relaxation at night so they can readily drift off to sleep,” Dr. Small adds.
If you’re curious about sleep meditation, take a look at our in-depth guide, which includes everything from breathing techniques, to visualisation, guided meditation and body scanning.
5. Alter other lifestyle habits
Dr. Small’s final tip focuses more on what we can do outside our bedrooms to influence our sleep.
“Get enough exercise during the day, avoid excessive smoking or drinking of caffeinated beverages late in the afternoon, and limit alcohol consumption,” he advises.
Our guide on how to exercise for better sleep has tips on when and where to do your workouts, as well as details on the importance of a cool down. Plus, we compiled some of the best bedtime drinks to try if you’re looking to avoid caffeine and alcohol at night.
Meanwhile, Dr. Small also suggests integrating certain relaxing activities into your nighttime routine.
“Find ways to wind down before bedtime (e.g., listen to soothing music, read a relaxing book),” he says, adding that “a warm shower or bath just prior to bedtime can be relaxing and make it easier to fall asleep.”
Does sleep deprivation impact health and longevity?
I asked Dr. Small for more insight into the effect of sleep deprivation on our health and longevity.
“While we sleep, our immune system produces cytokines, which are protective, infection-fighting substances that combat bacteria and viruses,” he says.
“Sleep deprivation reduces cytokine production, thus weakening the body’s ability to fend off infections and to recover from them,” says Dr. Small.
“Chronic insomnia increases a person’s risk for diabetes and heart disease,” he adds.
He notes that sleep deprivation increases the risk of people becoming overweight or obese, and explains that this occurs because of the impact on certain hormones.
Chronic insomnia increases a person’s risk for diabetes and heart disease
“Sleep modulates levels of two hormones that control feelings of hunger and fullness (leptin and ghrelin). Leptin sends signals to your brain that you have eaten enough, while ghrelin is an appetite stimulant.”
“Inadequate sleep alters the levels of these hormones, which often leads to unnecessary snacking and overeating later in the night,” he continues, adding that being too tired to exercise from lack of sleep can also contribute to weight gain.
Additionally, not getting enough sleep as a result of insomnia “raises levels of insulin after meals,” says Dr. Small.
He explains that, “insulin is needed to control blood sugar levels, and higher insulin levels increase fat storage and a person’s risk for type 2 diabetes.”
A lack of sleep can also cause a raft of other health issues, Dr. Small says, including problems with blood pressure control, raising inflammation levels in the body, and increasing one’s risk for heart disease and strokes.
He adds that “people with chronic insomnia are 2.5 to 4.5 times more likely to have an accident (e.g., falls, fender benders) than those with normal sleep patterns,” and notes that “chronic insomnia impairs cognitive abilities.”
Ultimately, if you find that an issue with your sleep is impacting you, it’s important to get medical advice.
“Anyone suffering from sleep problems that affect their ability to function or quality of life should consider seeing their doctor to search for an underlying cause, which can be mental or physical,” Dr. Small advises.
