The endocannabinoid system (ECS) is a powerful regulatory network in the body that plays a significant role in the motivation for voluntary exercise, as well as in the response to physical activity. In this series on cannabis and exercise, Part I explored how the ECS is activated by physical activity, influencing our drive to engage in movement. Part II highlighted how endocannabinoid receptors are present in vital organs, including the lungs, heart, and blood vessels, all of which are essential for exercise performance.
Australia’s interest in medical cannabis has grown, with its role in managing lifestyle and wellness under ongoing investigation. This article examines the ECS, the effects of fasting and exercise on blood THC levels, and implications for cannabis users in Australia.
How Endocannabinoids and Body Fat Interact
Endocannabinoids, or the body’s natural cannabinoids, are synthesized from dietary fats and play a crucial role in regulating metabolism. Similarly, plant cannabinoids such as THC are fat-soluble molecules that accumulate in adipose (fat) tissue. This indicates that body fat and the rate at which it is burned can influence the release of stored THC into the bloodstream, a factor that could be relevant to both recreational and medical cannabis users in Australia.
This raises an intriguing question: Could burning body fat release enough THC into the bloodstream to have measurable effects, or even potentially cause a psychoactive response?
Effects of Fasting and Exercise on Blood THC Levels
Numerous studies, both on animals and humans, have investigated whether fasting and exercise influence blood THC levels. In one rodent study, rats were administered THC daily for five days, followed by a “wash out” period of three days. Some rats were then fasted for 24 hours. The fasted rats showed higher blood concentrations of THC-COOH, a THC metabolite commonly measured in drug tests, than non-fasted rats. However, there was no increase in THC itself.
A longer study exposed rats to THC for ten days, followed by a 24-hour fast. Blood tests showed higher levels of both THC and THC-COOH in fasted animals, although the increase in THC was relatively modest compared to THC-COOH.
While these animal studies offer insights, human research provides a closer look at how fasting and exercise may impact THC levels in Australians, particularly among the growing community of medical cannabis users.
Human Studies: Exercise, Fasting, and Blood THC Levels
Human studies on fasting and exercise have produced intriguing results, albeit with some limitations. In a study involving six regular cannabis users, participants engaged in 45 minutes of moderate-intensity treadmill exercise followed by a 24-hour fast. Surprisingly, blood tests revealed no significant increase in either THC or THC-COOH levels, which could be due to the duration of the fast. While a 24-hour fast is brief for humans, it represents a prolonged period for rodents, making the results from animal studies potentially less applicable to humans.
However, another human study offered further insights. In this study, 14 frequent cannabis users participated in a 35-minute stationary cycling session. Blood tests showed a significant increase in blood THC levels immediately after exercise, though THC-COOH levels remained stable. The effect normalized within two hours, indicating that elevated THC levels might be a temporary response to physical exertion.
An additional finding related to body mass index (BMI) and blood THC changes provides further food for thought, especially for Australians. Those with higher BMIs, and thus more body fat, tended to experience larger THC spikes post-exercise. This correlation suggests that individuals with more adipose tissue may see greater blood THC levels after exertion, potentially affecting medical cannabis patients with higher BMI in Australia.
Could Exercise and Fasting Get You “High”?
One natural question, particularly among Australian cannabis users, is whether this increase in blood THC could produce psychoactive effects. The available data suggests that this could be possible.
For instance, a study examining blood THC levels post-cannabis inhalation found that a 10 mg dose of THC resulted in a 10% increase in blood THC levels. Comparatively, exercise and fasting have been found to induce a roughly 15% increase in blood THC levels. This level of increase could theoretically produce psychoactive effects in some individuals, depending on factors like body fat, metabolism, and the individual’s overall cannabis tolerance.
Although these results provide a glimpse into how fasting and exercise could impact THC levels, further studies are needed to determine whether Australians who engage in fasting or high-intensity exercise after consuming cannabis could experience psychoactive effects.
Implications for Drug Testing in Australia
A common concern among Australians using medical cannabis, particularly those employed in industries requiring regular drug testing, is whether fasting or exercise might affect test results. While fasting and exercise may elevate THC in the blood, human studies thus far indicate that these activities do not lead to an increase in THC-COOH levels, the primary metabolite detected in most drug tests.
As such, while elevated blood THC may theoretically produce psychoactive effects, it does not seem to raise the risk of failing a drug test. However, since Australia’s drug testing regulations vary by state and employment sector, it’s wise for medical cannabis users to remain informed about their specific workplace policies and testing methods.
The Bigger Picture: Metabolism, Cannabinoids, and the Australian Lifestyle
Both the body’s own cannabinoids and those from plants like cannabis can influence metabolism, appetite, and fat storage. Given that endocannabinoids are produced from dietary fats, they directly impact metabolic health. For Australians exploring cannabis as a wellness tool, understanding the interactions between lifestyle choices, such as diet and exercise, and the ECS could enhance both safety and efficacy.
As more Australians adopt medical cannabis for health reasons, it is beneficial to understand how factors like body fat and physical activity impact its effects. Tailoring these lifestyle habits may allow individuals to better manage cannabis intake, reduce unintended effects, and make more informed health decisions.
Conclusion: A Cautious Approach for Australians
Australians incorporating cannabis into their wellness routines or managing medical conditions can benefit from understanding the effects of physical activity and fasting on cannabinoid levels. The evidence suggests that elevated blood THC levels due to exercise or fasting are temporary and unlikely to trigger positive drug tests, but may have a mild psychoactive effect, especially in those with higher body fat.
As research progresses, Australians may gain deeper insights into how the endocannabinoid system interacts with lifestyle factors, empowering them to make health choices that align with their needs. For now, medical cannabis users in Australia are advised to monitor how exercise and diet affect their experience and consult healthcare providers on best practices.
