Cannabis and hemp have both been present and taken part in the development of early human civilization and culture for over 12,000 years (1). The plant was originally used for its strong fibres, but evidence of smoking cannabis already appeared 6000 years ago in China, probably as part of religious rituals and for medical use (2, 3, 4). (Curious about the history of cannabis? Read more in Newsletter 1) 

Thus, it is not surprising that the plant’s evolution has been driven by mankind, in accordance with our then-current needs (e.g., medical or textiles) and culture (i.e., religious ceremonies). In a way similar to coffee or tea, the individual plants with the greatest desired effects (and flavor) spread their genes further, resulting in the major strains we now have today. Over the course of this relationship, humans experimented with different means of consuming cannabis, to better experience the plants’ psychoactive concoction of cannabinoids and terpenes. In this newsletter we will describe the three most common modern methods of consuming cannabis. These include inhalation (smoking and vaporizing, respectively), and oral ingestion (i.e., edibles) as well as their benefits and potential hazards for both the recreational and medical consumers. 

Today, inhalation and in particular smoking, via a joint, blunt or bong for example, is the most common method of consuming cannabis in the western world (6, 7). Inhalation of cannabis results in direct feedback (aka effect) to the consumer, allowing for easy self-regulation of the intensity of the experience (commonly known as “high”) and avoiding adverse effects (i.e., paranoia, dizziness, or anxiety). Inhalation is the preferred method of consumption when requiring or desiring a quasi-direct effect from cannabis. The effects of inhaling cannabis also don’t last very long, peaking within 30 minutes and decreasing following the hour (8, 9). This is useful when cannabis is used for medical purposes, as it can be used to induce short-term relief or stimulation in patients, for example against chronic pain, insomnia, epilepsy or lack of appetite (2, 3).

Joints are the most common method of recreational cannabis consumption. However, similarly to a cigarette (and often mixed with tobacco), the burning of cannabis releases over 2000 potentially harmful and cancerogenic compounds (i.e., carbon monoxide) (2, 9). But what about the non-tobacco smokers you ask? Well, they will often smoke pure cannabis joints, which unfortunately are also dangerous (2). Additionally, joints are often smoked with carton filters or tips. However these filters don’t actually filter out any harmful or large compounds, but function to maintain structural integrity and to decrease the heat of the smoke being inhaled. In recent years, carbo-active filters have increased in popularity as they advertise a healthier, cleaner smoke, however there is a lack of recent in-depth scientific literature to back up these claims (10).  But a new, healthier, and some will say more efficient, method of inhaling weed was developed recently: vaporizers! Vaporizers heat up the constituents of cannabis (THC, CBD, and terpenes) below combustion temperature, resulting in what some describe as “flavored air” (2, 9, 11). This method of consumption is particularly popular for people that can’t smoke, for example cancer patients or simply people trying to avoid or cut down on their tobacco use. Furthermore, vaporizing is considered nearly twice as efficient a method of consuming cannabis than joints, requiring less cannabis to extract the same amount of THC as a joint (12). When smoking, it is thought that about 30-50% of the THC of the plant is lost during combustion, whilst vaporizers are shown to release a vapor with a concentration of THC of 30 to 61% of total-vapor components (12, 14).   Studies have shown that ≈0.3g in a joint and ≈0.1g in a vaporizer result in similar THC-blood concentrations, although the biochemical reasoning behind this effect is yet to be accurately described (12, 13). It is therefore not surprising that many cannabis connoisseurs are swapping to the newer (and healthier) process of vaporizing their cannabis (2, 9, 11). The major drawback of vaporizers is that good quality ones are still expensive, often bulky and require regular maintenance.

Oral ingestion of cannabis, via foods or liquids (i.e., teas) is thought to be the oldest method of consuming cannabis. Reports in China written by the father of surgery Hua T’o (AD 110-207), discuss a concoction of cannabis-infused wine used to anaesthetise patients prior to a surgical operation (2, 4).  Edibles are gaining popularity in the western world as they result in a very different high, due to the slow, long-term release of compounds into the bloodstream. Therapeutic use of edibles is particularly suited in cases requiring symptomatic release over a long(er) period of time (2, 3, 15). For example, severe coughs – that could even be worsened by inhaling – or menstrual pains. However, the accurate dosage and effect varies from individual to individual, much more than smoking or vaping. This is due to our different, individual metabolisms, with variations of 6 to 20% of the THC found in the edible being absorbed into the bloodstream depending on the person’s metabolism (12). There are also a variety of external factors such as mood, health, and current appetite. All of which have a strong influence on the functioning of our digestive system (16).  

Recreationally, edibles are often considered a special treat due to their different and longer lasting effect. Moreover, like vaporizers, edibles are a much healthier method of consuming cannabis than smoking (2). High quality edibles are often highly searched for in countries with a decriminalized and legal status like the Netherlands or Canada, and can range from savory foods (eggs, or even a burger) to sweets (cake, candy). However, when made at home, edibles are time consuming and result in unknown THC concentrations and homogeneity in the product, occasionally resulting in a dampened effect compared to what was expected (2, 12). But more commonly,  homemade edibles consumption results in the user getting more high than what he bargained for. Unlike inhalation, the edibles’ effect isn’t felt until thirty to forty minutes after ingesting. Furthermore, the THC absorbed into the bloodstream is a stronger form of THC metabolized by the liver (12, 17). This makes it much harder for the user to regulate the high they expect, and much easier to take a higher dose than was anticipated, resulting in negative effects such as paranoia or dizziness. It is important to note that the effects of cannabis do not only change based on the consumption methods, but can also vary a lot between frequent and occasional smokers, based on their individual efficiency of absorption (12).

What about you? Have you tried all three methods of consuming cannabis? Do you have a favorite one or are you intrigued in trying a new one out? Let us know in the comments down below!*

*The Adriaan van Royen Foundation does not promote the use of legal or illegal drugs in any way. With our research we hope to inform a growing global audience and contribute to harm reduction for users. Always talk to your doctor when you consider using cannabis for medical reasons.