When you finally lie in bed after a stressful day, you can’t wait to fall asleep. Finally, you get your much-needed rest after a long day at work. But when sleep finally comes, it doesn’t last long. You suddenly wake up, gasping for air.
If this happened to you, you might have low blood oxygen saturation. Are oxygen levels between 95% and 98% acceptable? And is it bad when they fall below 90% or even 88%? In this article, we’ll answer every question you might have about your oxygen levels during sleep.
Summary
Oxygen levels during sleep of 88% or 90% are most commonly considered as bad and levels below 90% can lead to hypoxemia. On the other hand, sleep oxygen levels of 95% or 98% are considered within the normal range and are, therefore, good.
In this article, we also look at the following:
- The best oximeters
- Why do your levels drop?
As we tested a few of the oximeters, our testing found out:
- Best overall pulse oximeter: Innovo Deluxe iP900AP
- Best overall cheap pulse oximeter: Mibest OLED
- Best pulse oximeter with an app: Wellue
- Best affordable pulse oximeter with an app: Wellue Pulse Oximeter
Is an oxygen level of 88/90 to 95/98 bad when sleeping?
An oxygen level above 95% is never bad. So if your reading shows 96% or 98%, you have nothing to worry about. Although 100% saturation is preferable, some fluctuations are within known standards.
Values below 95% often suggest hypoxemia but only if it happens while you’re awake. When you sleep, your breathing slows down. As a result, your blood won’t carry much oxygen. But this doesn’t matter during sleep. Since your body is resting, it doesn’t need as much of it.
Therefore, values as low as 88% are still acceptable at night.
4 best FDA-approved pulse oximeters
Although you can get blood tests to measure your saturation, this invasive method isn’t as accessible. Consider using pulse oximetry instead. Oximeters are devices that effectively measure your saturation (SpO2, for short). All you have to do is place them on your finger and wait for your reading.
Not sure where to find a decent one? We’re one step ahead of you. Consider one of these 4 oximeters we reviewed:
Best overall pulse oximeter
We loved everything about this oximeter. Thanks to its small size, you can carry it with you on the go. It makes it perfect for athletes who want to measure their SpO2 and pulse after exercising. Make sure you stand still while performing the readings for maximum accuracy.
| Brand | Innovo Deluxe iP900AP |
| Battery Life | 40 Hours |
| Color | Deluxe Off White |
| Number of Batteries | 2 AAA batteries are required. (included) |
| Our rating | It’s the product we’d be most likely to recommend. |
Pros
- We believe this is a great model.
- It feels better built than some of the cheaper options.
- It has a sleek look to it.
- More than 40,000 people have reviewed it.
- For accuracy, we believe this is the best product.
Cons
- We wish it connected to an app and tracked your data.
- If you’re really on a budget, you can find something cheaper.
- The material still feels a bit cheap.
Best overall cheap pulse oximeter
The best thing about this oximeter is its price. If you just need a quick reading without spending too much money, look no further than here. The interface is easy to use even if you don’t use much tech. What’s more, you can carry it with you wherever you go.
| Brand | Mibest OLED |
| Battery Life | 40 Hours |
| Color | Black |
| Our rating | It’s a great alternative to our most-preferred recommendation. |
| Recommended Age | >12 Years Old |
Pros
- It’s a great value purchase.
- It has more than 18,000 reviews.
- We found it had a better hinge than other cheap options.
- It’s very easy to use.
- It has a bunch of different options.
Cons
- It doesn’t have an associated app.
- It doesn’t seem to work well on kids.
- It occasionally takes longer to get a reading.
Best pulse oximeter with an app
If you don’t like figuring out how a new device works, this oximeter is the right choice. It comes with an app that displays the readings and saves your data. It allows you to track your long-term saturation. Though a bit costly, it’s easily our go-to option.
| Brand | Wellue |
| Are Batteries Included | Yes |
| Battery Life | 40 Hours |
| Color | Black |
| Our rating | It’s our top recommendation if you want an app. |
| Recommended Age | >12 Years Old |
Pros
- We love that it connects the data to an app.
- The app does what it’s supposed to.
- You get great value from this product and its price.
- It feels comfortable in hand.
Cons
- It feels a bit cheap.
- The documentation isn’t very good.
- It’d be great to figure out how to measure overnight data easily.
Best affordable pulse oximeter with an app
We offer you this alternative if you loved the idea but disliked the price. It is cheaper than our previous recommendation but achieves similar results. Though not as advanced, at least it won’t leave a dent in your wallet.
| Brand | Wellue |
| Are Batteries Included | Yes |
| Battery Life | 1 years |
| Color | White |
| Our rating | It’s a great runner-up with an app. |
| Recommended Age | >12 Years Old |
| SpO2 Range | 70%-100% |
Pros
- This device also connects to an app.
- As one reviewer pointed out, it also worked on our toes. We had to test it.
- It can potentially save you money by avoiding having to do a sleep apnea test.
Cons
- The device itself feels a bit cheap.
- It’s the device we trust the least in terms of accuracy.
- It’s clearly the lowest quality of these suggested devices.
What is a normal oxygen saturation level?
When awake, your saturation should be 100%. However, any number above 95% is still considered an acceptable oxygen level. While these values might seem uncompromisingly high, there is a reason for that. Your body requires oxygen to produce energy. Many vital organs, such as the heart and brain, can’t function without it for too long.
In some cases, your optimal saturation level might be lower. Lung diseases and sleep apnea will naturally lower your saturation. If you suffer from either one, a saturation of 90% is still an acceptable oxygen level.
During sleep, your saturation might drop even further. It isn’t a cause for concern as long as it doesn’t get below 88%. When you sleep, your entire body rests, and most bodily processes slow down. It extends to breathing as well.
But if your notice your saturation drops below these standard values, you should seek medical attention immediately. This condition is called hypoxemia, and many unpleasant symptoms often accompany it. Left unchecked, it can lead to permanent damage.
What does it mean when your oxygen level is low?
When your oxygen level drops too low, you develop a condition called hypoxemia. It simply refers to oxygen deficiency in your blood. If your saturation reaches below 95% when you’re awake, you suffer from hypoxemia. During sleep, the acceptable threshold is slightly lower. It’s also lower if you have been diagnosed with lung disease.
But what does hypoxemia look like? This condition is extremely unpleasant. You develop serious symptoms that will impact your quality of life. Headaches and dizziness are both very common symptoms of low oxygen levels. It is because your brain needs maximum saturation to function properly. Eventually, this might grow into a lack of coordination or even general confusion.
Apart from these brain-related symptoms, you’ll also notice breathing difficulties. You might feel short of breath all the time. Your body will try to compensate for the low saturation by increasing your blood circulation. As a result, your heartbeat will become faster. Coughing and wheezing are rarer but possible symptoms.
In severe cases, you might develop cyanosis. It refers to blueish skin, lips, and nails. Cyanosis happens when your red blood cells don’t carry sufficient oxygen.
Critical hypoxemia can even be life-threatening. Low oxygen levels can cause you to lose consciousness and stop breathing. If this happens, your vital organs may shut down, and death soon follows.
To prevent this from happening, you should try to keep your saturation within the normal range.
Why does my oxygen level drop when I lie down?
Sleep is the time when your body gets its much-needed respite. To achieve this, all bodily processes slow down. Your breathing slows down as well.
Since sleep doesn’t require much energy, you don’t need as much oxygen at night. It’s, therefore, natural for your oxygen level to drop when you lie down. Your lungs also rest and thus don’t operate at their maximum capacity. They simply don’t need to.
Your saturation can get as low as 88% at night. Although it might sound low, it’s perfectly natural. But if it ever gets below this value, something is very wrong. If this is the case, seek out a doctor immediately. Otherwise, the consequences could be permanent and even lethal.
What happens when your oxygen level drops to 70?
Any oxygen level below 95% is outside the established norm. A saturation of 75% is already bad, but if it drops down to 70%, you might develop very serious symptoms of hypoxemia. The most common ones are terrible headaches, dizziness, and breathlessness.
At such low levels, you might also faint. You should visit a doctor without delay if you have such a low saturation. You will likely need supplemental oxygen to compensate for the hypoxemia.
At such a low level, your organs will begin to suffer. They will lose their function and might even shut down entirely. Loss of consciousness is a strong possibility too. You should visit a doctor without delay if you have such a low saturation. You will likely need supplemental oxygen to compensate for the hypoxemia.
How low can your oxygen level go before you die?
Some people tolerate low oxygen levels better than others. For most, saturation below 80% can often cause serious problems. These include headaches, dizziness, and even loss of consciousness. Your vital organs may also begin to fail. Others might withstand levels as low as 50% though this is rare.
At the moment of death, your oxygen level will drop to 0%. If it is above this value, your body will keep fighting to remain alive. However, this doesn’t mean it will win this fight. Critically low oxygen levels can shut down your entire respiration system. Without timely intervention, this often proves fatal.
You should, therefore, always seek medical attention if your levels drop below 80%. Even if it doesn’t prove serious, it’s always better to be safe than sorry.
At what oxygen level is a ventilator needed?
Although pulse oximetry is a great way to check your saturation, it isn’t the most accurate method. The readings can often be off by 2% or even 4%. As a result, values just slightly below 95% are generally still fine. But when they drop below 90%, you might need a ventilator.
It is when the symptoms such as headaches and dizziness start to develop. And the only way to fight them is to boost your saturation back to normal. A ventilator achieves just this.
The values differ slightly when you sleep. Since your saturation drops naturally while you rest, readings below 90% are acceptable oxygen levels. But they should not fall below 88%. If this happens, you likely suffer from hypoxemia and might need a ventilator.
Alternatively, you can boost your oxygen levels by eating healthy food and exercising. Following breathing exercises might also bring your saturation back to normal levels. However, a ventilator is still the most effective method when your levels drop too low during sleep.
How to check your oxygen level without an oximeter?
Suppose you don’t want to invest in an expensive machine. In that case, you can use the following 3 alternative ways to check your oxygen level:
Measure your respiratory rate
It is easily the simplest method to track your saturation level. You don’t need any kind of equipment other than a stopwatch. Luckily, most phones come with this feature.
First, set your stopwatch for 1 minute. Then, count the number of times you breathe in. Do this until the timer runs out. The ideal breath count should fall below 24. You might suffer from hypoxemia if your respiratory rate exceeds 30 breaths per minute.
Look out for symptoms.
Another way to check if you have hypoxemia is to evaluate your symptoms. Although only your doctor can diagnose you accurately, assessing these symptoms can give you a general idea about your condition.
The most common symptoms are headaches and dizziness. It happens because your brain doesn’t get enough oxygen. If you have hypoxemia, your heartbeat will likely increase, and your breathing will become uneven. In some cases, you might develop blueish skin and lips. It is called cyanosis and often points to insufficient oxygen levels.
Suppose your respiratory rate is above 30, and you notice most of these symptoms. In that case, there is a strong chance you will suffer from hypoxemia.
Use smartphone apps
Apps such as HemoSpO2 and CarePlix come with many health-tracking features. They can measure both your oxygen level and pulse rate. All you need to do is place one finger on your smartphone’s flashlight and wait for the results.
Keep in mind that these might be less effective than specialized devices. For more accurate readings, we recommend checking out our list of pulse oximeters. We’re certain you will find an option that will fall within your budget.
Your recommended oxygen level doesn’t change with age. Thus, a child should also have a saturation of 95% or more. Levels below 90% are often a reason for concern and might require immediate medical attention. A 75% oxygen level is often critical and can even be life-threatening.
Your child’s saturation might fall as low as 88% during sleep, but this is still normal. When you rest, your breathing slows down. As a result, your saturation decreases naturally. You have nothing to worry about unless it drops below 88%. If so, seek a doctor as soon as possible.
Conclusion
To sum up, your saturation represents the amount of oxygen flowing in your veins. It travels through your blood via red blood cells. Every single organ in your body needs a steady supply of this life-giving gas to function properly. Thus, your saturation should ideally be 100% or at least above 95%. Lower values suggest hypoxemia and might be a reason to visit your doctor.
At night, your saturation drops naturally. It is because your whole body rests, not just the mind. Many bodily processes slow down, including your breathing. It is, therefore, normal for your oxygen level to fall as low as 88%. You should have nothing to worry about as long as it remains above this level.
You can measure your saturation via pulse oximetry. Alternatively, you can count your breaths per minute. Doctors might often recommend using a ventilator to treat your hypoxemia. However, you can also fight this condition by eating healthy food and exercising. Taking slow deep breaths also helps.