While a lot of people discuss the potential health benefits of CBD and other cannabinoids, it’s also important to talk about any possible negative effects. The science and research into CBD is still new and emerging, which means that we don’t necessarily have a solid understanding of how it impacts our bodies – both in regards to the positive and the negative. Understandably, we want to know that what we’re consuming isn’t going to harm us, exasperate any health problems, or lead to further complications down the road.

So what do we know about the risks of CBD use? The science might still be emerging, but thankfully, there is some information out there.

From the Health Authorities

When looking for information, it’s important to see what health authorities are saying about the safety and risks of CBD use. Since 2017, the World Health Organization (WHO) has suggested that CBD has a good safety profile. They state that recreational CBD use does not appear to be linked to any health issues, and in contrast, may have potential to be used as a treatment for a variety of concerns. However, WHO also cites the need for more research. There’s a lot we still don’t know about how CBD impacts our bodies, especially when it comes to any supposed health benefits, and substantial health claims can’t be made until we know more.

The Government of Canada has also issued information about cannabis use and risks, discussing everything from long-term use, age, pregnancy, and breastfeeding. While much of the information they have pertains to cannabis (THC) use, and not necessarily CBD, it’s still a good resource full of important information for consumers.

Since this article was first published, Health Canada came out with a safety review of CBD in 2022. They reiterate many of the things we’ve said and are going to continue talking about below: CBD appears to be well tolerated with minimal, mostly benign side-effects, but we need more research to know more, especially when it comes to long-term effects. Their report is easy to read and comprehensive, and a great reference if you’re looking to know more.

State of the Science

The current research we have also seems to suggest similar safety findings, even at high doses. What side effects do exist are reported to be relatively benign, including things like drowsiness, digestive issues, and mood changes. Since we’re all different and everyone’s body will react differently, it’s important to check with your doctor and follow the advice of your local health authorities.

One literature review about the safety and side effects of CBD found that within animal studies, some adverse health effects were noted, such as reproduction and central nervous system issues. However, the study also acknowledged that the amount of CBD being administered was far above regular consumption levels. Ultimately, the study determined that medication interactions appear to be one of the largest issues with regular CBD consumption. It also acknowledged that a lot more research is needed before we know anything for certain, especially when it comes to long-term health effects.

We’ve also seen conversations about CBD impacting heart health or amplifying the risk of things like psychosis and schizophrenia. However, we haven’t seen research to back this up yet, and these issues appear to be linked more to THC use than CBD. As well as this, the research we have so far suggests that CBD is non-addictive, but rather, may have the potential to help treat addiction. While the World Health Organization acknowledges the findings of some of these studies, it does not recommend CBD for medical use at this time because more evidence is needed.

Medication Interactions

Put simply, CBD can change the way certain medications are metabolized by our system. Essentially, CBD has been found to either increase the amount of medication remaining in your body, or diminish it. Either this means that medication isn’t there when you need it to be, or you’re possibly risking an overdose. While being on the lookout for grapefruit warnings is a good start, it’s always best to check in with your doctor and local health authorities in order to ensure you’re being as safe as possible.

Since CBD and medication interaction is a much larger topic, we’ve spoken about it in more detail here.

Full Spectrum and THC Inclusion

It’s important to note, particularly when it comes to Full Spectrum CBD, that some people appear to be more sensitive to THC than others. Although typically the amount of THC within a Full Spectrum product is low, it’s not uncommon to hear people still reporting adverse THC side effects, such as anxiety and paranoia. Like we mentioned earlier, Canada has released information about the potential risks of cannabis, more specifically referring to THC use. Basically, if you’re taking Full Spectrum CBD, you might be at greater risk of experiencing some of the more negative effects of THC, but this isn’t necessarily always the case.

There’s also some research that suggests CBD may be able to counteract some of the adverse effects of THC. Another review, however, points out that research is still limited, and understanding the interaction between CBD and THC requires a lot more study, especially when it comes to potential health effects.

Another under-researched area is how other cannabinoids, terpenes, and flavonoids may impact our bodies. Right now, CBD and THC are the cannabinoids we have the most research for, so we have much less of an understanding of things like CBN or CBG and how they may negatively impact us. It’s all fine to claim that CBN could possibly make you extra drowsy, and we have a lot of anecdotal reports to support this, but at the end of the day, we’re still waiting for the science to catch up.

Liver Concerns

In terms of liver issues and CBD, contradictory evidence exists. Since the science is so new, we haven’t seen any health authorities discussing the topic yet. However, we thought it was important to include anyway. As time goes on and we develop a stronger understanding of the science, sources like WHO and the government of Canada will make more information available.

Since this article was first written, Health Canada did acknowledge the potential negative effects on the liver in their safety report, recommending that folks with liver challenges should stay away from CBD in general.

In regards to the science we do have at the moment, one well-known study found that large amounts of CBD do cause liver damage when consumed by mice. However, it appears the doses used in the experiments were far above normal consumption levels. By contrast, this study suggests that CBD may have a positive impact on our liver’s health, though this study was also conducted with animals, so human applicability might be harder to assess. Another study, conducted with 839 adult participants, found that CBD doesn’t appear to cause liver damage. However, this study was funded by several CBD companies, and besides the linked webpage, we were unable to find the actual study results and academic paper.

More recently, this study conducted with athletes found that CBD does seem to have an impact on the liver even at low doses, especially in people who were particularly vulnerable to liver issues. This research review concluded that there’s evidence in animal trials of CBD negatively impacting the liver, and the few human trials available have shown that CBD may impact liver enzymes. This study, however, found contradictory results, concluding that CBD may actually help when it comes to stress-induced liver damage, largely due to its anti-inflammatory effects.

Ultimately, it appears that the topic is still up for debate, with questions of human applicability and dosage in the forefront. Until more research is conducted, unfortunately we don’t know enough to say anything for certain.

Unregulated Products

Not all CBD products are sold through the legal market. This means that even if a product claims to be organic, have a certain level of CBD content, or have no additional additives, this isn’t always the case. A 2017 sample trial found that many companies misrepresented the CBD content in the actual product, with the vast majority of goods either under or over-labeling themselves. We’ve seen evidence of this lately, with THC inflation being a hot, contested issue within the industry. This can make CBD more challenging to dose accurately. With this in mind, it’s important to buy your products from a licensed, reputable cannabis retailer. Be on the lookout for certificates of analysis (COAs), and other forms of company transparency, including not making any health claims that can’t be backed up by the research yet.

TL;DR

According to The World Health Organization, the risks of taking CBD appear to be relatively low. While this may seem like good news, it’s important to recognize that the science is still really new. We don’t know enough to say anything for certain yet. Especially when it comes to liver issues or long-term, high-dose use, we don’t have a lot of answers. As such, it’s always important to exercise caution, talk to your doctor, consult your local health authorities, and start low; go slow.