Sleep, Aging & Wisdom

Kristen Rainey

January 1, 2023

Do you ever wistfully reflect on your ability as a teenager to enjoy nine-hour uninterrupted stretches of restorative sleep on a regular basis, without any effort?  How easy it was to take that for granted. 

Unfortunately, as we get older, it becomes hard for us to get that kind of sleep– in both quantity and quality. Some of us can’t fall asleep. Others wake frequently during the night or at 4 am, much earlier than we’d like to start our day. By our mid-late 40s, we’re typically getting 60-70% less deep sleep compared to our teenage years; by our 70s, we’re getting 80-90% less.*  It’s a myth that we don’t need as much sleep as we did in our earlier adult years. Why is sleep more of a challenge as we get older? What can we do about it? And why should we care?


For one thing, the amount of melatonin, our sleep hormone, that our bodies generate decreases as we get older. This means it’s even more important than ever to pay attention to anything that interferes with melatonin production and our overall sleep-wake cycle, known as our circadian rhythm. 

Blue light from our screens (our phones, laptops, and tablets) suppresses the onset of melatonin and makes it harder to fall asleep and stay asleep. Avoid screens several hours before bed and keep lights dim in the evenings. Consider investing in blue blocker glasses to protect your eyes from the blue light.   
Expose yourself to natural sunlight early in the day.
Keep a regular schedule of going to bed and waking up around the same time, all seven days of the week.
While short naps during the day can be helpful, taking naps longer than 90 minutes– especially late in the day– can reduce the sleep pressure your body needs to fall asleep the following night. Experiment with timing and duration to find what works for you.

Why should we prioritize sleep?

Weight control 

Many of us spend inordinate amounts of time focused on diet, yet we’re casual about our sleep. If we gave that same level of attention to prioritizing sleep,  one of innumerable benefits would be weight control. Why? It’s all come back to hormones. When we’ve slept poorly, our bodies produce less leptin, the hormone that normally signals a sense of feeling full. At the same time, when we’ve slept poorly, our bodies make more of the hormone ghrelin which makes us feel hungry. So our bodies’ hormonal signals are making it more challenging to control our eating habits. Furthermore, when we’re underslept, we’re craving less healthy foods. We’re more likely to choose a chocolate croissant or donut or bagel than a healthier choice like a bowl of steel cut oatmeal. Furthermore, when we’re underslept, we release more cortisol which interferes with our body’s ability to properly absorb nutrients. Our gut health is better when we’re well rested.

Alzheimer’s prevention 

One important function of deep sleep (also known as NREM sleep) is the flushing away of metabolic refuse inside our brains. Without sufficient sleep, amyloid plaques build up in the brain, making us more susceptible to Alzheimer’s.

Impact on aging 

Getting sufficient sleep– in both quantity and quality– impacts the expression of our genes. We all have chromosomes which house our genetic material. A chromosome’s protective cap, a telomere, becomes damaged when we don’t get enough rest. This means our genetic code can’t operate as it should, which accelerates the aging process. In two biological twins with the same genetic material, the one consistently getting good sleep will look physically younger than the other.

Resilience & wisdom

Finally, when we’re well rested, we’re more emotionally resilient. One of the important functions of REM sleep (dreaming) is processing the emotionally challenging events of the day in a calm environment to emerge the next morning with a fresh perspective. Getting sufficient REM also allows us to process social cues better, such as others’ facial expressions. Finally, during REM, we connect concepts that might not come naturally to us while we’re awake. So it isn’t simply that better rest makes us more efficient and productive; it boosts our resilience, emotional intelligence, and wisdom.

*Matthew Walker, Why We Sleep.

This blog entry was originally published on 11/5/2020 on the Wisdom Well blog of Modern Elder Academy.