[00:01] of energy recovery or productivity, but there's another question that matters even more. What does poor sleep do to your arteries? Because plaque doesn't suddenly appear overnight. It builds up quietly for years, and some research
[00:14] suggests that the way you sleep influences how fast that process interesting is that the relationship isn't as simple as sleep longer and you'll be better off. Rather than asking, are you sleeping long enough? We
[00:27] should ask, are you sleeping in a way that protects your arteries? Or are you accumulation easier? So, in this video, I'm going to cover the relationship between sleep duration, sleep quality, and atherosclerotic plaque buildup. Over
[00:40] the last 10 years or so, many people have emphasized the importance of sleeping enough. They say, you need to sleep 8 hours for optimal health. But, is it really backed up by data? Studies often find that sleeping shorter than 6
[00:52] hours is associated with a higher risk of mortality, but so is sleeping over 8 hours. However, the lowest mortality risk is seen at 7 hours per night. This doesn't mean that sleeping 8 hours is necessarily bad for you. People who need
[01:05] to sleep over 8 hours do so because of some health problem. They're either hospitalized or they're sick with some disease that makes them sleep a lot longer. But, it also indicates that sleeping 7 hours is just fine, and it
[01:17] might be even a better sign of overall health. It's also clear why sleeping increase your mortality. It's just not enough sleep. Short sleep raises resistance, worsens your metabolic health, and makes you gain more body
[01:31] to the process of atherosclerosis and what's the relationship between sleep duration and atherosclerosis itself? A duration and atherosclerosis itself? A 2023 study on over 1,500 adults showed
[01:44] associated with increased atherosclerotic plaque, whereas sleeping over 9 hours was. Short sleep and daytime sleepiness were not associated with atherosclerotic plaque. That's quite surprising, isn't it? The mean age
[01:58] in this study was 64.7 plus or minus 8.5 years, which might indicate that in older people short sleep is more common and healthier people who sleep shorter do so because of being healthier, whereas older people who sleep very long
[02:12] have some sickness or comorbidity that makes them more tired and want to sleep sleeping shorter does appear to be associated with higher atherosclerosis. In this 2025 study on people over the age of 40, which is relatively young
[02:26] still, short sleep of less than 7 hours was associated with a higher 58% higher risk of plaque compared to sleeping 7 to 9 hours. They also had a 196% higher risk of greater plaque thickness and 157% higher risk of having multiple
[02:41] plaques. These associations were found in people with low to intermediate risk of cardiovascular disease, which means that even healthy people who slept less than 7 hours saw a greater risk. So, what's the absolute best sleep duration
[02:54] then? In this study on men aged 40 to 60, sleeping 7 hours resulted in the lowest prevalence of subclinical atherosclerosis in terms of coronary artery calcification. Coincidentally, this is the sleep duration that's often
[03:07] found to be associated with the lowest mortality risk as well as heart disease simple as that try to sleep 7 hours, but it does indicate that sleeping 7 hours is enough for otherwise healthy people. Sleeping even less than 7 hours might be
[03:21] fine for some people. In the large study on US adults I shared earlier, they duration and all-cause mortality and cardiovascular disease mortality. The lowest risk for both was seen at 7 hours a night, which makes sense. Less than
[03:34] that, as well as more than that, were associated with increased risk. However, sleeping 5 to 6 hours for both all-cause mortality and cardiovascular mortality were not statistically significant. The confidence interval for both exceeded
[03:47] 1.0, which means the results aren't statistically significant. So, based on this information, the real range for lowest risk could be 5 to 7 hours. I'm inclined to think that the 7-hour range is still safer and more suitable for
[04:00] most people, but it could mean that some people are able to sleep 6 hours without disease risk. However, what this does confirm is that the extreme sleep durations, less than 5 hours and longer than 8 hours, are significantly
[04:13] associated with higher all-cause and cardiovascular mortality. So, the range of 5 to 7 hours for otherwise healthy more people might be fine for not atherosclerosis risk, but it might not apply to each individual, and you don't
[04:26] want to take a risk necessarily by sleeping 5 to 6 hours. It's still better to lean towards the 7 hours and maybe even longer than that. But what about people with already existing plaque? In this 2025 study on patients with stable
[04:38] angina who got a CT scan, it was seen that better sleep in terms of longer sleep duration and lower PSQI score, which indicates better sleep quality, resulted in more stable plaques. Sleeping less than 5.5 hours was seen to
[04:51] vulnerability, whereas sleeping longer than 5.5 hours resulted in more stable plaque. The best range was 6 to 8 hours. So, even in people with already existing plaque in the arteries, the best sleep duration is 6 to 8 hours. What these
[05:06] studies find is that sleep quality matters a lot more than the sleep duration. In this study, higher sleep fragmentation and lower sleep duration were both associated with increased risk of subclinical atherosclerosis in people
[05:19] around the age of 40 to 45. Sleep duration only matters in the context of extremes, sleeping less than 5.5 hours or sleeping longer than 8 hours. In the range of the 6 to 8 hour range, sleep quality matters more than the sleep
[05:32] duration. 6 hours of high-quality sleep is better than low-quality 8 hours of sleep. Another important factor to this is consistency and regularity of your sleep regularity, going to bed and waking up around the same time, has been
[05:45] seen to be a bigger predictor of survival than total sleep duration. To quintile, participants went to bed and woke up within a 1-hour window daily. Those in the lowest quintile varied by 3 plus hours. It's no surprise then that
[05:59] sleep regularity also predicts atherosclerosis risk. In this 2023 meta-study, people with the highest irregularity in sleep had a higher risk of coronary artery calcification at over 300 calcium score as well as over zero.
[06:12] It was found for both irregularity in total sleep duration, which means that their total sleep duration varied over 120 minutes, as well as their sleep timing irregularity. The only thing found not to be significant was carotid
[06:25] intima media thickness, which reflects plaque in the carotid arteries and oftentimes soft plaque. Regular sleep in this study was considered to be less than 1 hour variation per night for sleep duration and less than 30 minutes
[06:37] for sleep timing regularity. So, it's best to go to bed within 30 minutes of your regular bedtime and sleep plus and minus 1 hour from your regular sleep duration. The reason I made this video is because I was interested myself. You
[06:49] a hectic sleep schedule since I was 18 years old up until the age of 28 or so. schedule and I was getting quite a worried. I thought maybe this hectic
[07:01] having some irregular sleeping patterns, maybe it would have increased my risk of some plaque. For what it's worth, I did get a photon counting CT scan recently. It's a more advanced and less radiation type of CT scan compared to the regular
[07:16] you can see both the hard plaque and soft plaque. Our results came back zero, plaque. Completely squeaky clean arteries. Now, of course, I was still young in this period, 18 to 28. Now, I'm 31, but in that 10-year time frame,
[07:32] maybe this 10 years isn't long enough to see any significant atherosclerosis. And Maybe 10 years for someone who is 60 years old would have a significant least for me in my age from the age of 18 to 28, it didn't have any effect. So,
[07:48] as a young person, you can probably get away with sleeping bad for even 10 years atherosclerosis. But, subclinical atherosclerosis already starts in their 20s for a lot of people. It's just that it's not common practice to measure
[08:04] these things in people who are 20 or 30 years old, not even 40 years old. The standard practice is to measure people's arteries in their 50s or 60s. So, in reality, a lot of average people already have atherosclerosis in their 20s. It
[08:16] just hasn't been measured. But, I did get it measured and my score is zero, fortunately. So, this video was mostly done to satisfy my own interest and to satisfy my own concerns whether or not poor sleep, short sleep increase my
[08:29] atherosclerosis. The answer is no for me for various reasons, but I never slept less than 6 hours. So, my sleep was around 6 hours to 7 hours on average and based on the research, it appears sleeping 6 to 8 hours in that window,
[08:42] there's no increased risk of atherosclerosis. But, on the extremes, sleeping less than 5.5 hours or if you sleep over 8 hours, that's associated other health reasons. But, nowadays, I sleep very good. Nowadays, I have
[08:55] years, I've improved my sleep a lot. If you want to know how I improved my sleep quality and sleep scores from 75 to 100, quality and sleep scores from 75 to 100, then check out this video next.