In order to make informed decisions about whether cannabis is right for you, it’s important to understand its active ingredients and how they activate the body and brain. 
What’s the endocannabinoid system?
It’s not surprising that many health conditions may be improved by cannabis, because almost every part of our brain and body is highly sensitive to the molecules in the plant. 

Our bodies have an entire system involved in balancing health, known as the endocannabinoid system. Similar to our immune system, parts of the endocannabinoid system are found throughout our entire body.

This includes our: 

• Brain

• Gut

• Immune cells

• Bloodstream

• Skin

    The CB1 receptor (THC’s target) is just one of the many parts that make up the endocannabinoid system.

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CBD vs. THC: How cannabis interacts with the body

 

The cannabis plant is unique because it produces a family of chemicals called cannabinoids. These chemicals all have a similar three-dimensional shape. However, subtle differences in the shape of these chemicals can have a big impact on how they make us feel.

The two most common cannabinoids are tetrahydrocannabinol (THC) and cannabidiol (CBD). Cannabis plants that produce mind-altering effects are typically high in THC, and cannabis plants with high CBD (and little or no THC) are legally defined as hemp.

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How does THC work, and what does it do?

Most of the mind-altering effects and side effects of cannabis are caused by THC. THC is the primary psychoactive molecule in the cannabis plant. 

THC causes mind- and mood-altering effects because it binds to special proteins (receptors) that cover the surface of most of our brain cells. The reason THC fits into these receptors is that its three-dimensional shape is very similar to a natural molecule made by our own brains, called anandamide.

THC’s effects are mostly due to binding at the CB1 receptor. The CB1 receptor is found in many brain regions involved in: 

• Thinking

• Planning

• Pain

• Bodily movements

• Learning

• Emotions

THC is even involved in the pain-relieving effects of cannabis. Generally, there are dose-dependent effects of THC. That is, there are more unwanted side effects at higher doses of THC. Over the last several decades, there has been a consistent increase in the strength or amount of THC present in cannabis.

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What can CBD help with?
The second-most-common molecule in the cannabis plant is cannabidiol, or CBD. Unlike THC, CBD does not cause problems with body coordination or thinking. In laboratory settings, CBD can reduce the negative side effects of THC such as anxiety and paranoia.

Many people report that CBD helps with pain and sleep, but it’s possible these effects could partly happen because of the placebo effect. At very high doses, oral CBD can relieve anxiety, but anxiety-relieving doses are nearly 10 times higher than a typical dose recommended by doctors. 

Much more research is needed, but CBD may be an important tool to protect brain cells and support mental health. Although studies are ongoing, CBD may one day be considered a therapy for psychosis, addiction, and traumatic brain injury, as well as other neurological disorders. 

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What are the medical benefits of cannabis?
Human research for cannabis’s effectiveness for many diseases is still ongoing. The most well-studied benefits of cannabis are:

• Pain relief

• Improved sleep

• Reduced nausea and vomiting

• Improved appetite

• Improved quality of life

One common finding among many studies is that although cannabis may not treat the main symptoms of a disease (cancer, for example), it improves a person’s quality of life. That is, although their disease itself does not get better, people are able to cope with daily life more easily when they use cannabis. 

For neurological conditions and multiple sclerosis
There are several FDA-approved cannabis-like medications. That is, these medicines are cannabinoids, or cousins of the unique chemicals produced by the cannabis plant. 

In fact, cannabidiol (Epidiolex) — prescription-level CBD that is used to treat a rare form of epilepsy in children — is made directly from the plant. 

Cannabis is also used for diseases like multiple sclerosis (MS). Research is ongoing, but some studies suggest that cannabis may also help neurodegenerative diseases like Parkinson’s and Alzheimer’s.

For nausea, vomiting, and low appetite
Two other FDA-approved medications with medical benefits are nabilone (Cesamet) and dronabinol (Marinol). These are synthetic cannabinoids, not made from the plant. They are prescribed for nausea, vomiting, and low appetite.

For pain
In addition to these FDA-approved medications, the cannabis plant (and products made with cannabis) have genuine health benefits. The most common reason people use cannabis is to manage pain. 

Recent research suggests that cannabis could be a safer choice compared to other pain-relieving drugs such as opioids and benzodiazepines. Cannabis may be safer because its side effects are not life threatening. Opioids and benzodiazepines, however, cause thousands of accidental drug overdoses and deaths every year.

For sleep
Both people with and without chronic diseases report that cannabis improves their sleep. 

Some studies show that cannabis may help people fall asleep faster, but it may not prevent waking up in the middle of the night.

Although research is still ongoing, cannabis could also be helpful for people with sleep disorders such as restless leg syndrome.

For mental health conditions: Anxiety and PTSD
People also commonly use cannabis for anxiety and post-traumatic stress disorder (PTSD). Although anxiety and depression are often experienced together, research suggests that prolonged periods of cannabis use could actually make depression worse.

People use cannabis to treat many other health ailments, such as autoimmune and inflammatory diseases. More research is needed to understand how effective cannabis is for these conditions. 

What are the personal or recreational benefits of cannabis?
People have many different reasons for choosing to use cannabis, but some commonly reported reasons are relaxation, stress relief, and to generally feel better. Many patients report using cannabis for both symptom relief and recreation. The medical and personal use of cannabis is more of a spectrum than two distinct categories.

In 2020, researchers examined the impact of federal legalization in Canada and found the following: 

• 56% of people who took the survey said that cannabis is beneficial for their quality of life. 

• 46% of people also reported that cannabis is beneficial for their mental health. 

Can alcohol be substituted with cannabis?
In recent years, the reduced stigma of cannabis has caused some people to consider substituting alcohol with cannabis. Studies show that when cannabis is legalized, alcohol sales decrease. In heavy drinkers, researchers found that cannabis reduced alcohol consumption by almost one-third. Some substance abuse treatment programs are even considering cannabis as a harm-reduction tool for people with alcohol use disorder.

Can cannabis be used with exercise?
Both cannabis and alcohol impair a person’s ability to drive, but there are many other activities that people can safely combine with cannabis. For example, cannabis is commonly combined with exercise. Athletes — and endurance athletes in particular, like long distance runners — report that cannabis enhances exercise enjoyment and recovery from workouts. Contrary to historic stereotypes that cannabis causes laziness, people also report that cannabis helps them feel motivated to exercise in the first place. 

Interestingly, some studies show that long-term cannabis use has been associated with lower rates of obesity and other metabolic diseases like diabetes. There may be a link between cannabis, exercise, and metabolic health, but more research is needed.

Does cannabis improve sex or creativity?
Research has shown that cannabis can increase sexual desire and satisfaction, especially for women. Some artists and musicians claim that cannabis is an important tool to stimulate the creative process. Some people even report using cannabis to aid their spiritual development. 

What are the short-term side effects of cannabis?
Although cannabis could relieve symptoms or help you relax, there are also side effects. These include:

• Dry eyes

• Dry mouth

• Dizziness

• Reduced body temperature

• Faster heart rate

Some people also experience feelings of uneasiness or anxiety, especially if they are new to using cannabis. This is generally caused by accidentally taking a dose of THC that is too high. If you start to feel anxious or uneasy after consuming cannabis, there are a lot of self-care steps you can take while you wait for the effects to wear off. 

Other side effects of cannabis are experienced as medical benefits for some people. For example, cannabis stimulates appetite, sometimes referred to as “the munchies.” This side effect can be helpful for people with cancer who have low appetite. Similarly, cannabis can cause drowsiness, which can be helpful for people who have trouble sleeping.

What are the real risks of cannabis use?
It can impact your coordination and thinking.
Cannabis is well known to impair body coordination and driving. It also impairs thinking and decision making. Long-term cannabis use has been associated with memory and attention problems, even while people are not under the influence of THC. These impairments could negatively impact work or school performance. 

It can interact with other medications.
The molecules in cannabis may interact with certain types of medications. Many prescription drugs are broken down by the liver, and both THC and CBD can interfere with this process. If you are taking any medications with a “grapefruit warning” on the label, be sure to discuss your cannabis use with your doctor. You may need to have regular blood tests to make sure your cannabis or CBD use does not cause a harmful drug interaction.

It can impact teens’ mental development.
Certain vulnerable populations should be very wary of cannabis, or avoid it altogether. Decades of research have shown that cannabis interferes with brain development, and teenagers should wait to use cannabis until at least age 21. Cannabis use at an early age has also been linked with an increased risk for psychosis and other mental health problems. Cannabis use can also make the symptoms of bipolar disorder worse.

It’s harmful if you’re pregnant or breastfeeding.
Both pregnant and breastfeeding mothers are advised to avoid cannabis, due to long-lasting mental and emotional impacts on their children. THC has been linked with low-birth weight due to changes in the placenta. Also, THC remains in the human body for a long time after cannabis is consumed, especially when people consume cannabis orally (edibles or beverages). Because THC easily passes into breast milk, it is safest to avoid all forms of cannabis consumption while breastfeeding.

It can be addictive.
Cannabis can be addictive, and THC is primarily responsible for its rewarding or addictive potential. Like many natural behaviors and other substances (sex, gambling, sugar, and nicotine, for example), cannabis can be used excessively with negative consequences. 

Surveys conducted prior to the recent wave of cannabis legalization suggest that up to 27% of cannabis users will develop a substance use disorder. However, a 2020 study of Canadian recreational cannabis users found that only 2% of people ever seek professional help for a cannabis problem. Additional long-term studies are needed to understand the true risk of developing cannabis use disorder. 

If you think you may be addicted to cannabis, or any other substance, it’s important to reach out to your healthcare provider or a trusted person for help and support.

It can cause physical and mental problems, if used excessively.
A new concern among healthcare professionals is the rise of a condition known as cannabinoid hyperemesis syndrome (CHS). CHS is a condition where excessive cannabis use causes people to experience cycles of nausea and vomiting. Because cannabis has long been used to treat nausea, people often consume more, making matters worse.

Healthcare providers have a hard time diagnosing CHS due to lack of awareness. Although the strongest predictor of CHS is excessive cannabis use, there also appears to be a genetic link to the disorder. Hot showers and topical capsaicin are used for symptom relief, but there is no known cure other than ceasing cannabis use.

In general, the greatest risks of cannabis use happen with heavy cannabis use and large amounts of THC. In fact, inhaling highly concentrated THC (known as dabbing) has caused some people to experience psychotic symptoms such as extreme paranoia and self-harm.

It can create legal challenges for people.
Cannabis use can sometimes make housing, employment, and healthcare more complicated. Because of federal cannabis laws, people may be denied housing or some forms of public assistance if they are cannabis users. 

How to decide if cannabis is right for you
People respond differently to cannabis, and the best way to know if it might help your symptoms or lifestyle is to try a small amount in a safe, responsibility-free environment. It can be helpful to keep a journal to track what you consumed, and how it made you feel. Be prepared to feel some side effects, but also rest assured that these feelings are temporary. For millions of people worldwide, the personal and medical benefits outweigh the side effects.

Teens, pregnant and breastfeeding mothers, and people with personal or family history of serious mental illness should avoid cannabis. Similarly, if you have a history of problematic substance use or addiction, you may be particularly sensitive to the addictive effects of cannabis. Also, because it can interact with certain medications, it’s important to discuss cannabis use with your healthcare provider.