I've said this before and will gladly say it again:

If the benefits of sleep could be bottled and put in pill form, the line would be out the door and around the corner.

Most of us have the opportunity to take advantage of these benefits every night.

It shouldn't be groundbreaking that adequate sleep is paramount for your overall physiology.

Frequently, we trade priceless hours of sleep for scrolling on our phones, late-night events, or binging our favorite show. Occasionally, the tradeoff is worth the price. However, the data shows that a consistent pattern of poor sleep can take a toll.

In today's newsletter, we will look at the effects of poor sleep on our overall health, the effects of being a shift worker, and 7 easy tactics to improve sleep quality and duration.

How Does Poor Sleep Affect Your Health?

Sleep is my Achilles heel.

After 25 years of being on call as a cardiovascular surgeon, my sleep schedule has been thrown off.

If sleep is something you are working to improve, I am right there with you.

When I refer to poor sleep, I mean chronic poor sleep. A single night of poor sleep may impair cognitive performance, but the effects are minuscule in the long run.

Regular nights' rest of less than 6 hours of sleep is associated with a​ 7-17% increase in type-2 diabetes, coronary heart disease, stroke, and certain cancers​. Additionally, sleep deprivation also weakens your immune system

Why does poor sleep affect your health?

We are genetically coded to have a consistent sleep-wake cycle. Our bodies are placed under stress when we disrupt this cycle.

These are the effects on your body:

1. Autonomic Response: studies show increased blood pressure and sympathetic tone (fight-or-flight response). Both impact cardiovascular risk.
2. Metabolic & Appetite Disruption: insulin sensitivity and glucose regulation are reduced. Leptin, ghrelin, cortisol, and melatonin secretion are affected because our internal clock is disrupted.
3. Mood & Brain Health Effects: Poor sleep affects our memory consolidation, emotional regulation, and increases the risk of depression and anxiety.

Can You Sleep Too Much?

Interestingly, there is a U-shaped relationship between sleep and risk.

Meaning less than 6< and more than >9 hours of sleep leads to increased risk. The sweet spot for most people lies between 6 and 9 hours of quality rest.

Similar to undersleepers, individuals who consistently oversleep have an increased risk of ​all-cause mortality​ and ​dementia​ (especially in older individuals).

The body of research and mechanisms for undersleepers are robust, while those for excess sleepers are less well established.

It's worth noting that there is a clear distinction between chronic oversleepers and the occasional "catch-up" sleep. Striving for extra sleep to recover from sleep debt is generally beneficial.

Shift Workers: Unique Risks

We receive frequent messages and comments about the health risks of shift work.

The benefits of shift work vary by individual circumstances. Assessing your priorities is crucial because there are clear trade-offs for your health. As mentioned earlier, we are genetically designed for a specific sleep/wake cycle, and it's not nocturnal.

Shift workers can experience ​a 20-35% increase in cardiovascular disease, type-2 diabetes, and cancers​, alongside a ​40-100% increase in workplace-related incidents and accidents.​

Duration as a shift worker matters and is dose-dependent. ​Every 5 years of shift work is associated with an increase in cardiovascular disease and all-cause mortality.​

There are mitigation strategies, but the only way to completely reduce health risks is to return to a normal sleep/wake cycle.

7 Tips to Improve Sleep Quality and Quantity

Ultimately, I had to change my relationship with sleep to truly make a difference.

Sleep is one of the few pillars of health; the harder you try to force it, the worse it gets.

Here are 7 takeaways that have improved my sleep:

1. Set a timer to go to sleep
2. Get outside during the day
3. Keep the room cold (my wife and I use the ​EightSleep​)
4. Make your bedroom as dark as possible
5. Don't eat 3 hours before bedtime
6. Brown or white noise background noise
7. Avoid alcohol

None of these tips will change your sleep overnight.

Consistently compounding a majority of these over time will help set the stage for a good night's rest.

Admittingly I was in the "I'll sleep when I die" camp.

Now sleep is one of my top priorities.

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Only the best,

Jeremy London, MD

P.S. Don't forget to follow my podcast for free on ​Spotify​ or ​Apple Podcasts

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