Monday Myth Buster #4
Does Holding in Cannabis Smoke Increase Absorption or Is It a Myth?
If you’ve ever smoked cannabis, you’ve probably heard the age-old advice: “Hold it in for as long as possible to get higher.” Some claim that keeping the smoke in your lungs for 10, 20, or even 30 seconds allows your body to absorb more THC, maximizing the effects. But is this actually true, or is it just another cannabis myth passed down through generations of stoners?
To answer this, we need to dive into the science of THC absorption in the lungs, examine studies on inhalation techniques and blood THC levels, and explore how this information can affect both recreational users and medical patients looking for efficient cannabis consumption. Spoiler alert: You might be wasting your breath.
How THC is Absorbed in the Lungs: Does Holding It In Help?
When cannabis smoke enters the lungs, THC is absorbed almost instantly. The lungs are designed for rapid gas exchange—just like oxygen from the air is absorbed into the bloodstream in milliseconds, so is THC.
The Science of Lung Absorption
The alveoli in the lungs (tiny air sacs where gas exchange occurs) absorb cannabinoids within seconds of inhalation.
Studies show that at least 95% of THC is absorbed within the first few seconds of holding in the smoke (Agurell et al., 1986).
Any time spent holding your breath beyond this point does not significantly increase THC absorption but does increase exposure to harmful byproducts like tar and carbon monoxide.
In essence, if you’re holding your hit in for more than a few seconds, you’re not getting more THC—you’re just starving your brain of oxygen and inhaling more toxins.
Do Studies Show a Difference in Blood THC Levels Based on Inhalation Techniques?
Several studies have tested the idea that holding in smoke increases THC absorption, and the results don’t support the myth.
A landmark study published in Pharmacology, Biochemistry, and Behavior tested different breath-holding durations (0 seconds, 10 seconds, and 20 seconds). The results showed that holding cannabis smoke in longer did not significantly increase blood THC levels but did increase levels of carbon monoxide, indicating higher toxin exposure (Zuurman et al., 2008).
Another study in the Journal of Cannabis Therapeutics found that the depth of inhalation mattered more than the duration of holding it in. A deep inhale followed by normal exhalation led to the highest THC absorption, while prolonged breath-holding made no meaningful difference in THC levels (Gieringer et al., 2004).
A 2017 study confirmed that maximum THC absorption occurs almost immediately after inhalation and that any perceived “stronger high” from holding in smoke is more likely due to oxygen deprivation rather than increased THC intake (Huestis et al., 2017).
Why Do People Feel “Higher” When Holding It In?
Even though science debunks the idea that holding in cannabis smoke increases THC absorption, many users swear it enhances their high. This sensation is likely caused by oxygen deprivation and CO2 buildup rather than increased THC intake.
Holding your breath too long deprives your brain of oxygen, leading to a lightheaded, dizzy sensation that can mimic or intensify the effects of cannabis.
The longer you hold in smoke, the more carbon monoxide you inhale, which can cause a temporary head rush similar to hyperventilation.
In other words, the intensified feeling isn’t THC working harder—it’s your brain running low on oxygen.
Implications for Recreational Users and Medical Patients
For Recreational Users: Stop Holding It In!
If you’re a casual cannabis user who just wants to get the most out of your weed, the best strategy is a deep inhale followed by a normal exhalation after a couple of seconds.
Holding it in for longer doesn’t increase the amount of THC absorbed—it only increases exposure to tar, carcinogens, and lung irritation.
A deep, steady inhale is more important than how long you hold it in.
Oxygen deprivation might make you feel higher, but it’s not actually increasing the THC in your bloodstream.
For Medical Patients: Efficient Consumption Matters
For medical cannabis patients, efficiency in THC absorption is crucial. Patients using cannabis to treat pain, nausea, or appetite loss need the maximum benefit with minimal lung damage.
Vaporization may be a healthier option, as it delivers THC effectively while reducing harmful combustion byproducts.
Sublingual tinctures and edibles offer THC absorption without the need to inhale at all.
If smoking is preferred, a normal inhalation technique (without prolonged breath-holding) is the most effective way to get relief.
Are There Any Cases Where Holding It In Helps?
The only scenario where holding in an inhale may have some benefit is when using vaporizers or dabs with highly concentrated cannabinoids. Since vaporized cannabis doesn’t contain as many combustion byproducts, a brief 3-5 second hold could allow for slightly more absorption. However, even in these cases, extreme breath-holding is unnecessary.
The idea that holding in cannabis smoke increases THC absorption is a widespread but scientifically unsupported myth. THC enters the bloodstream within seconds of inhalation, meaning prolonged breath-holding is unnecessary and only increases exposure to toxins.
For both recreational users and medical patients, the key to effective cannabis consumption is deep inhalation rather than breath-holding. So next time someone tells you to “hold it in for as long as possible,” you can confidently respond: “That’s just a myth—I’ll exhale when I’m ready.”
