People have used various herbs and plants for centuries to improve their health as well as heal ailments. One of these plants is a succulent called kanna, or Sceletium tortuosum in Latin. This plant is found in South Africa and native tribes have used it to alleviate pain, improve mood, suppress hunger, and promote relaxation.
Kanna has been unknown in the US for a long time, but it has recently gained popularity. So, what is kanna used for, and what does science have to say about its uses?
What Is Kanna?
Kanna is a low-growing succulent plant found in South Africa. Native tribes have used it for centuries for its mood-promoting benefits, and it’s even been a part of rituals and healing practices.
This plant absorbs moisture from seasonal rains which allows it to thrive throughout the year. It tends to spread around and cover a lot of ground area, and in addition to its succulent leaves, kanna also features fibrous roots and pink, yellow, or white flowers.
The San and Khoikhoi people used kanna leaves to clench thirst, reduce fatigue, and lift mood during rituals or travels across the desert. They usually fermented it and called it kauwgoed, which translates to “chewable or something to chew.”
What Does Kanna Do?
It seems that kanna could relieve pain, promote calmness, suppress hunger, improve mood, and reduce stress. The leaves, stems, and flowers all contain alkaloids responsible for these effects. The most important ones are mesembrine and mesembrenone, as they are the most active.
These alkaloids act as serotonin uptake inhibitors, affecting specific membrane transporters such as 5-HT. Serotonin is a neurotransmitter vital for mood, perceived happiness, sleep, food intake, and the regulation of different behaviors. Chronic low levels of serotonin are linked with impaired moods and depressive states.
By inhibiting serotonin uptake, kanna’s alkaloids prevent its degradation in the neurons. That prolongs the effects of serotonin which has a strong influence on the brain and overall well-being.
Besides blocking the 5-HT receptors, these alkaloids also inhibit PDE4, an enzyme in charge of breaking down signal molecules vital for cell metabolism. So, when PDE4 is blocked, more signaling molecules remain active which boosts metabolism and energy levels.
Mesembrine from kana modifies the activity of another membrane cell transporter called vesicular monoamine transporter two, or VMAT2 for short. VMAT2 transports neurotransmitters like serotonin, dopamine, and GABA, which have many vital functions in our central nervous system. The modulation of this transporter could be the reason behind perceived calmness and relaxation after taking kanna.
What Does Kanna Feel Like?
The effects of kanna depend on how you ingest it. Traditionally, people have chewed fermented leaves, stems, or flowers which resulted in a short-term, euphoric-like feeling with a relaxation phase that followed.
Drinking kanna tea has a milder and more calming effect, while vaporizing it enhances the euphoric properties.
How Long Does Kanna Stay in Your System
We don’t have precise data on how long kanna stays in our bodies. According to the anecdotal evidence, people mostly feel the effects for one to four hours after the ingestion.
Although kanna has been used for centuries in South Africa, it is relatively unknown to most other parts of the world. We’ve learned more about it in recent years, but there hasn’t been enough time to conduct thorough research on its benefits and side effects.
Most studies up to date have used Zembrin, which is a dietary supplement containing kanna plant extract. Here are the effects we have observed so far.
Anxiety and Stress Relief
The number one reason people take kanna is to relieve stress. Researchers believe kanna is able to accomplish this by inhibiting PDE4 and 5-HT receptors in the amygdala. A small study discovered that Zembrin reduced anxiety-related amygdala activity. However, the study included only 16 healthy participants, which is quite a small sample size.
A 2011 study in mice showed that low doses of kanna extract mildly improved stress response. Although the mice exhibited reduced anxiety, researchers observed higher levels of certain inflammation biomarkers and slight suppression of immune response.
More human trials have been done in recent years that support kanna’s anxiolytic effects. A 2017 study followed older individuals who took Zembrin supplements for six weeks. Researchers used questionnaires, psychometry, and quantitative EEG to assess the impact on mood, cognitive function, and stress levels. The results confirmed that kanna could improve mood, decrease anxiety, and even improve some aspects of cognitive function.
Even one dose of Zembrin could reduce perceived anxiety in healthy individuals during stressful events such as public speaking. Zembrin could potentially be effective towards reducing acute stress during job interviews, big presentations, and other stressful events by making us calmer.
However, it’s important to mention that most studies examining the effects of Zembrin were led by a doctor who was also the co-founder, as well as the medical and scientific director, of the company that produced this supplement. Since he had a clear financial incentive to sell his company’s products there’s the potential for bias in these studies, however, that doesn’t have to be the case, but it’s certainly something to think about.
Fighting Off Depression
People who consume kanna claim that it boosts their mood and helps them to experience fewer symptoms of depression. We saw how it could reduce stress and anxiety, and in turn, it should help fight depression symptoms as well.
One rat study discovered that kanna extract does have antidepressant properties. However, the animals experienced severe side effects such as ataxia which makes it difficult to control muscles and perform coordinated movements.
Some case reports have shown doctors were able to eliminate depression symptoms successfully by using kanna extract. However, these should be taken with a grain of salt as they were reported mainly by the same doctor in charge of the Zembrin studies.
Depression is closely linked with inflammation, and research shows that kanna has anti-inflammatory properties that could help with low-grade inflammation and cytokine-induced depression.
Antidepressant properties were observed in another rat study, where the effects of Zembrin were compared to escitalopram, a common antidepressant drug with a similar mechanism of action to kanna. The results showed that supplementation with Zembrin was as effective in alleviating depression symptoms as escitalopram, highlighting the potential of this supplement.
Some people report that taking kanna extract reduces physical pain. It seems that mesembrine is the main reason for that, as researchers have observed analgetic properties of this alkaloid in rat models.
Traditional medicine practitioners would rub kanna on the legs of hunters since they believed it reduced pain. They would also give it to pregnant women experiencing pains and aches, as chewing kanna helped them. However, we need more human studies to determine if kanna provides significant pain relief.
Khoikhoi and San people used kanna to improve alertness, among other things. People taking kanna extract today also report that it helps their cognitive performance. However, there is little scientific evidence to support these claims.
One study in rats showed that Zembrin could enhance cognitive function and act as an antidepressant and analgesic. A small study in 21 healthy humans observed the effects of Zembrin over three weeks. The results showed improvements in cognitive function when taking this supplement, demonstrating its cognitive-enhancing effects. People also experienced better mood and sleep.
Other Possible Benefits
By reducing stress and anxiety as well as promoting relaxation, kanna should help people sleep better. Anecdotal evidence supports that claim as many people taking these supplements report better sleep. Some studies have also observed these effects.
Historically, kanna has been used to suppress appetite and reduce hunger. Although no studies support these claims, scientists suggest that some alkaloids found in kanna’s extract could bind to cholecystokinin-1. This receptor is vital for managing appetite, and when activated, we feel less hungry. That’s how kanna could help control hunger.
Kanna has anti-inflammatory and antioxidant properties that may slow down certain chronic conditions like obesity and diabetes. In addition, its active compounds are great at scavenging free radicals that damage our cells, and they may even have anti-HIV properties.
Kanna Side Effects
Because kanna is not extensively researched, we are unsure about all of its potential side effects. A randomized trial concluded that taking 8 mg or 25 mg of Zembrin for up to three months is safe and well-tolerated by healthy adults. Some reported side effects included headaches, abdominal pains, and infections of the upper respiratory tract. However, people in the placebo group (not taking Zembrin) experienced these symptoms at the same frequency.
Other people have reported feeling nauseous when they start taking kanna, but it quickly resolves.
As we lack proper kanna safety studies, certain groups of people shouldn’t use it including:
- Pregnant and breastfeeding women
- People with chronic conditions
- People taking certain antidepressant drugs like selective serotonin reuptake inhibitors (SSRIs) or monoamine oxidase inhibitors (MAOIs)
How To Take Kanna
If you are researching how to use kanna, the traditional way would be to chew leaves, stems, or flowers. People also drink or vaporize it, and the effects vary depending on the ingestion method.
Kanna teas often combine kanna with honeybush for enhanced soothing effects. When ingested this way, kanna has a milder impact that promotes calmness and relaxation. That’s why drinking kanna tea would be a perfect way to unwind after a stressful day, or you can drink it before bedtime for better sleep.
Kanna powder is typically made from fermented kanna leaves, which increases the availability of bioactive compounds. Kanna powder can be mixed with water or other beverages, and it should improve alertness, boost mood, and reduce stress.
Some people smoke kanna powder, which produces a euphoric effect as it quickly affects your central nervous system.
The easiest way to take kanna is in capsule or tablet form. You should stick to the manufacturer’s recommended daily dosages for the best effects. Try taking it at different times of the day and see what produces the most benefits.
Where To Buy Kanna
Although kanna has reached the US market, it’s still relatively hard to find it. Amazon has a limited selection of kanna products, and finding the right online supplier is difficult. Most of them are not transparent about the dosages, benefits, and other vital product information.
One of the vendors with a good selection of kanna products is Nootropics Unlimited. The company sells kanna tablets, capsules, and powder, and they highlight that the products are strictly for laboratory and research purposes. Although the company has an excellent kanna selection, many customers have complained about the lack of information, overall transparency, and customer support.
For kanna tea, Traditional Medicinals appears to offer the best product. The company has been making high-quality teas for almost 50 years. All ingredients used in their teas are organic and ethically sourced. In addition, they pay special attention to the quality of their teas, as they employ a team of experts who work on the herb formulations and rigorous testing.
Also read our review on the best kava.
Studies You Can Read About Kanna
- HPLC analysis of mesembrine-type alkaloids in Sceletium plant material used as an African traditional medicine (Journal of Pharmacy & Pharmaceutical Sciences 13.4 , 2010)
- Pharmacological actions of the South African medicinal and functional food plant Sceletium tortuosum and its principal alkaloids (Journal of ethnopharmacology 137.3 , 2011)
- Serotonin and brain function: a tale of two receptors (Journal of Psychopharmacology, 2017)
- Serotonin Involvement in Physiological Function and Behavior (Basic Neurochemistry: Molecular, Cellular and Medical Aspects, 1999)
- Dopaminergic neurons inhibit striatal output via non-canonical release of GABA (Nature, 2012)
- Acute Effects of Sceletium tortuosum (Zembrin), a Dual 5-HT Reuptake and PDE4 Inhibitor, in the Human Amygdala and its Connection to the Hypothalamus (Neuropsychopharmacology, 2013)
- The effects of Sceletium tortuosum in an in vivo model of psychological stress (Journal of ethnopharmacology, 2011)
- Effect of Zembrin® on Brain Electrical Activity in 60 Older Subjects after 6 Weeks of Daily Intake. A Prospective, Randomized, Double-Blind, Placebo-Controlled, 3-Armed Study in a Parallel Design (World Journal of Neuroscience, 2016)
- Sceletium tortuosum (Zembrin®) ameliorates experimentally induced anxiety in healthy volunteers (Clinical and Experimental, 2020)
- Effects of Sceletium tortuosum in rats (Journal of ethnopharmacology, 2014)
- Kabbo’s !Kwaiń: The Past, Present and Possible Future of Kanna (The Ethnopharmacological Search for Psychoactive Drugs; Founding Director of HG&H Pharmaceuticals (Pty), Ltd.: Bryanston, South Africa, 122-150.)
- Immunomodulatory effects of Sceletium tortuosum (Trimesemine™) elucidated in vitro: Implications for chronic disease (Journal of ethnopharmacology, 2018)
- An acute dose-ranging evaluation of the antidepressant properties of Sceletium tortuosum (Zembrin®) versus escitalopram in the Flinders Sensitive Line rat (Journal of Ethnopharmacology 284 ,2022)
- Electropharmacogram of Sceletium tortuosum extract based on spectral local field power in conscious freely moving rats (Journal of ethnopharmacology, 2016)
- Proof-of-Concept Randomized Controlled Study of Cognition Effects of the Proprietary Extract Sceletium tortuosum (Zembrin) Targeting Phosphodiesterase-4 in Cognitively Healthy Subjects: Implications for Alzheimer’s Dementia (Evidence-Based Complementary and Alternative Medicine , 2014)
- Sceletium tortuosum may delay chronic disease progression via alkaloid-dependent antioxidant or anti-inflammatory action (Journal of physiology and biochemistry, 2018)
- Sceletium tortuosum demonstrates in vitro anti-HIV and free radical scavenging activity (South African journal of botany 106, 2016)
- A Randomized, Double-Blind, Parallel-Group, Placebo-Controlled Trial of Extract Sceletium tortuosum (Zembrin) in Healthy Adults (The Journal of Alternative and Complementary MedicineVol. 19, No. 11, 2013)
Editor’s note: we are regularly updating this review. If you see any problems, weird interpretations of the data, or just want to say hi, please reach out to firstname.lastname@example.org.