Magnolia bark is a popular herb used for gut health and stress-induced anxiety. It comes from the Magnolia tree famous for its large, dramatic flowers.
The bark of the magnolia tree has been used for thousands of years in both traditional Chinese and Japanese medicine. In both cultures, it has been used to encourage sleep, reduce inflammation, and support nervous disorders.
Modern research shows that magnolia bark and its isolated phytochemicals may be helpful for gastrointestinal issues, troubles with sleep, anxiety, and cancer.
In this article, we will look at the health benefits of magnolia bark, its safety, and its history.
Table of Contents
- What Is Magnolia Bark?
- Health Benefits of Magnolia Bark:
- Magnolia Bark Safety:
- Naming & Taxonomy:
- History & Traditional Use:
What Is Magnolia Bark?
Magnolia bark is the bark of the Magnolia tree which is part of the Magnoliaceae family. The magnolia is a deciduous tree that has multiple species that are native to eastern Asia, as well as the Americas.
Different species of magnolia include:
- Magnolia acuminata
- Magnolia denudate
- Magnolia obovata
- Magnolia officinalis (the most common varietal)
Between species, the flowers vary in shape, color, and smell, however, the bark can be interchangeably used in medicine.
Magnolia bark has a sedative effect on the body and has been used to promote sleep and ease anxiety. It is also commonly used to support gastrointestinal health.
Modern research shows that magnolia bark has anti-inflammatory, antioxidant, stress, and weight-reducing effects. These various health benefits are attributed to magnolol and honokiol, two phenolic compounds present in magnolia bark.
Magnolia bark is a well-researched herb, however, not many human trials are available. Many of its traditional uses have been scientifically tested (via animal and in vitro trials) and show promising results.
Health Benefits of Magnolia Bark:
Below are the top researched-backed magnolia bark benefits for health.
1. May Reduce Stress & Anxiety
In a 2022 study, a supplement containing magnolia bark and phellodendron bark (Phellodendron amurense) was used to reduce stress and cortisol levels in 56 moderately-stressed participants. The herb combination reduced salivary cortisol, a marker of stress, by 18% in comparison to the placebo. The blend also improved the mood of the participants receiving the supplement.
Another study using the same magnolia/phellodendron blend found that it reduced anxiety levels in premenopausal female adults. It should be noted that while anxiety was temporarily reduced, there was no long-term effect after participants stopped using the blend.
In an animal trial, researchers used an isolated active constituent of magnolia bark, honokiol, to test its anxiolytic effects on stressed mice. Honokiol was found to reduce anxiety levels in the mice without slowing down motor functions.
An animal study utilizing Magnolia officinalis bark extract proved to reduce anxiety while having a neuroprotective effect. The extract was able to regulate protein levels in the brain that are indicative of anxious behavior. Researchers noted that the extract was enriched with one of magnolia bark’s active constituents, honokiol.
In a mouse study, honokiol proved to elicit the anxiolytic effect in Hange-koboku-to and Saiboku-to, two medicines used in traditional Chinese medicine and Kampo (traditional Japanese medicine). Researchers ensured that there was a steady dose of honokiol throughout the study (while the other ingredients varied) in order to confirm their hypothesis.
Summary:Research indicates that magnolia benefits the body by helping to reduce stress and anxiety. Large scale trials are needed to verify these effects.
2. May Improve Weight Loss
The benefits of magnolia bark have been shown to help support weight loss through stress reduction and management.
In a clinical trial involving healthy, overweight, premenopausal women, Magnolia officinalis extract (MOE) demonstrated a weight loss effect on those that overate when they were stressed. Researchers found that MOE reduced evening cortisol levels, a stress marker, which led to a decrease in nighttime snacking.
A recent study demonstrated that a magnolia/phellodendron bark supplement reduced stress-related eating in 56 moderately-stressed participants. As a result, participants who took 500mg/day (250mg in the morning, and 250mg in the evening) saw an improvement in weight loss.
Summary:Early research suggests that magnolia bark may support weight loss. Large scale clinical trials are needed to verify these findings.
3. May Support Gut Health
Magnolia bark benefits gut health and healthy digestion.
The health of the digestive system is important because it controls how your body processes and eliminates the food that you consume.
In a recent animal study, Magnolia officinalis extract improved and normalized levels of gut bacteria in mice. Balanced bacteria in the gut promotes healthy digestion, as well as improved mental health. The extract also made the mouse’s fur glossier and improved bowel movement regularity.
An animal study focusing on magnolia’s two active constituents, magnolol and honokiol, demonstrated that these phytochemicals have the ability to promote bowel movements. Magnolol and honokiol achieve this effect by improving the intestinal movement that helps move digested food through the gastrointestinal tract.
In a trial involving Magnolia officinalis extract (MOE), stomach ulcers in mice were healed after receiving 30-120mg daily of the extract. One of the extract’s most prominent effects was a reduction in inflammation.
Summary:Animal and lab-based studies show that magnolia bark may support a healthy gut microbiome. Clinical research needs to be conducted to verify these effects in humans.
4. Anti-Cancer Properties
Active constituents in magnolia bark have shown in laboratory studies to have anti-tumor effects, and promote the death of cancerous cells. Cancer is one of the leading causes of death worldwide.
In a preventative animal study, magnolia bark’s active constituent, honokiol, was able to prevent the development of skin cancer. Researchers believe magnolia bark’s ability to activate specific proteins was responsible for the anti-cancer effects.
Researchers found that a combination of tumor radiation and honokiol had the capability to reduce a mouse lung tumor by 78%. The combination was tested against an independent honokiol dose and an independent radiation dose. Both independent doses were not as effective in shrinking the tumor as the combination dose.
An in vitro and in vivo study discovered that honokiol inhibits breast cancer cells from growing and could boost the effects of other drugs used against breast cancer. Researchers go on to mention that there were no toxic effects associated with honokiol.
In another in vitro study, honokiol showed promising effects on oral cancer cells. Honokiol was able to prevent cell growth while inducing cancer cell death.
Another in vitro study involving magnolol proved to have similar effects in liver cancer cells. Magnolol inhibited cancer growth and reduced tumor size in vitro. It should be noted that results improved when dose size increased.
Summary:Initial lab-based studies show that constituents in magnolia bark, namely honokiol, may help to fight cancer. More in-depth research needs to be conducted to verify the use of magnolia bark for cancer.
5. May Improve Sleep
Research shows that magnolia bark benefits sleep quality. Getting adequate amounts of deep sleep is key for mental and physical health.
In fact, magnolia bark is thought to be one of the best herbs for sleep.
In a sleep study, honokiol was able to shorten the time it took for mice to fall asleep and increased the amount of time spent asleep. Researchers attributed these effects to honokiol’s potential to reduce anxiety and stress.
Researchers saw similar results in a separate sleep study using magnolol. Magnolol was also able to reduce the time it took for mice to fall asleep. In addition to this, the mice spent more time in deep sleep resulting in an overall higher quality of sleep.
In an 1869 medical text written by Dr. William Cook, he mentions that magnolia bark has relaxing qualities and can be used for someone who has nervous characteristics.
Further, noted herbalist Maria Noël Groves, mentions magnolia bark as a helpful herb for reducing nighttime sleep disturbances.
Christopher Hobbs, another well-known herbalist, also describes magnolia bark as supportive for inducing sleep.
Summary:Animal studies, as well as traditional usage, indicate that magnolia bark may be effective for improving sleep. Human clinical trials are needed to verify the benefits of magnolia bark for sleep.
6. Other Benefits
Other purported magnolia bark benefits include:
- Anti-inflammatory Properties: After isolating active constituents from magnolia stem bark, researchers found that both magnolol and honokiol elicited anti-inflammatory and antioxidant activities. Magnolia officinalis bark extract was able to reduce the trigger of inflammatory molecules at doses of 1 μg/mL and 10 μg/mL.
- Antioxidative Properties: After isolating active constituents from magnolia stem bark, researchers found that magnolignan B had the highest antioxidative potential.
While these various other health benefits of magnolia bark are interesting, human clinical trials are needed to corroborate these findings.
Summary:Magnolia bark has been tied to a wide variety of health benefits. Human clinical trials are needed to verify these findings.
Magnolia Bark Safety:
Safety Class: 2b (Not to be used during pregnancy)
Interaction Class: A
Magnolia bark is “generally recognized as safe” (GRAS) by the U.S. Food and Drug Administration.
Pregnancy & Lactation:
Not recommended for use during pregnancy and breastfeeding due to lack of data and evidence. Exception of use under qualified healthcare practitioner supervision.
Standard dosing for magnolia bark is as follows:
Decoction (tea made from bark or berries): 3 – 10g per person/day
Dietary Supplement: 200 – 800mg per person/day
Fluid Extract: 1.75 – 3.4 grams/day
Relora® (Magnolia/Phellodendron supplement): 250mg, 3x/day
Magnolia bark is not on the United Plant Saver’s “at-risk” list (sensitive to the impact of human activities).
Magnolia officinalis and Magnolia officinalis var. biloba cultivation only happens in China where the trees are cut down and the bark is stripped. This is an ecologically and environmentally unsustainable practice that is in the process of being revised.
Consider alternative sleep herbs that are harvested in a more sustainable manner.
Naming & Taxonomy:
Magnolia bark’s scientific name is Magnolia officinalis. It belongs to the Magnoliaceae family and is a deciduous tree that can grow 16 ft to upwards of 80 ft depending on the species.
They produce aromatic, large, and attractive flowers that sometimes bloom up to 8 inches in diameter.
Other common names include Cucumber Tree, Magnoliae cortex, Swamp Sassafras, Houpo, and Honoki.
Although commonly found in traditional Chinese and Japanese medicine, magnolia bark was also traditionally used in Native American medicine.
The magnolia tree has long glossy leaves and blooms from April to June. It produces mature red, conelike “fruit” from September through October when it opens up to display its seeds. Magnolia trees are very long-lived.
The bark is harvested from April to June where it is then dried in shade. Both the root and branch bark are used in therapeutic medicine. The bark is slightly decocted, steamed, and then rolled and dried once the color is purple-brown. The dried bark is strong-smelling and slightly bitter.
History & Traditional Use:
Magnolia bark has been used in traditional Japanese and Chinese medicine for thousands of years. As far back as the 7th century, Magnolias were cultivated in the gardens of Chinese Buddhist temples. Cultivation and therapeutic use also date back to the Native Americans and ancient Aztecs.
Although there isn’t much historical information on the magnolia tree and magnolia bark in Asia, there were sightings of the tree in North Carolina as early as the 16th century. The tree was later transported and cultivated in England.
The genus of the tree was named after the French physician, Pierre Magnol, who was a well-regarded botanist in the 17th century.
There are two classical formulas in which magnolia bark is still traditionally used.
The first one is called Banxia Houpo Tang (Chinese) is a formula that helps move stagnant qi in the throat, head, and solar plexus area.
The second formula, called Saiboku-To (Japanese) is a formula that is said to reduce asthma symptoms through its anti-inflammatory properties.
Further, in traditional Chinese medicine, the bark was used for the stomach, large intestines, and lungs. It supported stagnation, inflammation, anxiety, and bloating.
In Kampo or traditional Japanese medicine, magnolia bark was also used for gastrointestinal support.
Magnolia bark has been known to have a wide therapeutic scope, being especially supportive for anxiety and stress, and gastrointestinal issues.
Along with these health benefits, the bark also has strong potential for weight loss, reducing inflammation, and improving sleep.
Decoction of the bark, capsules, and TCM/Kampo blends are the most common preparations used for different types of ailments.
It is worth checking into magnolia bark if you have been experiencing any of the above indications. As always, make sure to consult your doctor before making any changes to your diet or adding a new supplement.
Borgonetti, V., Governa, P., Manetti, F., Miraldi, E., Biagi, M., & Galeotti, N. (2021). A honokiol-enriched Magnolia officinalis Rehder & E.H. Wilson. bark extract possesses anxiolytic-like activity with neuroprotective effect through the modulation of CB1 receptor. The Journal of pharmacy and pharmacology, 73(9), 1161–1168. https://doi.org/10.1093/jpp/rgab067
Chen, C. R., Zhou, X. Z., Luo, Y. J., Huang, Z. L., Urade, Y., & Qu, W. M. (2012). Magnolol, a major bioactive constituent of the bark of Magnolia officinalis, induces sleep via the benzodiazepine site of GABA(A) receptor in mice. Neuropharmacology, 63(6), 1191–1199. https://doi.org/10.1016/j.neuropharm.2012.06.031
Chilampalli, S., Zhang, X., Fahmy, H., Kaushik, R. S., Zeman, D., Hildreth, M. B., & Dwivedi, C. (2010). Chemopreventive effects of honokiol on UVB-induced skin cancer development. Anticancer research, 30(3), 777–783.
Cook, W. Ph.d.(1869). The Physiomedical Dispensatory. Cincinnati, OH: Ohio Valley Co. Retrieved from: https://www.henriettes-herb.com/eclectic/cook/MAGNOLIA_GLAUCA.htm
Garrison, R., & Chambliss, W. G. (2006). Effect of a proprietary Magnolia and Phellodendron extract on weight management: a pilot, double-blind, placebo-controlled clinical trial. Alternative therapies in health and medicine, 12(1), 50–54.
Grieve, M. (1931). A modern herbal. New York, NY: Harcourt, Brace & Company. Retrieved from: https://botanical.com/botanical/mgmh/m/magnol03.html#oth
Hobbs, C, Ph.D., L.Ac., AHG. (2017). Healing Sleep: The Art and Science of Sleep. Breitenbush, OR. Retrieved from: https://www.christopherhobbs.com/webdocs/class-handouts/various/Healing-Sleep-Breitenbush.pdf
Hu, J., Chen, L. J., Liu, L., Chen, X., Chen, P. L., Yang, G., Hou, W. L., Tang, M. H., Zhang, F., Wang, X. H., Zhao, X., & Wei, Y. Q. (2008). Liposomal honokiol, a potent anti-angiogenesis agent, in combination with radiotherapy produces a synergistic antitumor efficacy without increasing toxicity. Experimental & molecular medicine, 40(6), 617–628. https://doi.org/10.3858/emm.2008.40.6.617
Huang, K. J., Kuo, C. H., Chen, S. H., Lin, C. Y., & Lee, Y. R. (2018). Honokiol inhibits in vitro and in vivo growth of oral squamous cell carcinoma through induction of apoptosis, cell cycle arrest and autophagy. Journal of cellular and molecular medicine, 22(3), 1894–1908. https://doi.org/10.1111/jcmm.13474
Kalman, D. S., Feldman, S., Feldman, R., Schwartz, H. I., Krieger, D. R., & Garrison, R. (2008). Effect of a proprietary Magnolia and Phellodendron extract on stress levels in healthy women: a pilot, double-blind, placebo-controlled clinical trial. Nutrition journal, 7, 11. https://doi.org/10.1186/1475-2891-7-11
Kuribara, H., Stavinoha, W. B., & Maruyama, Y. (1999). Honokiol, a putative anxiolytic agent extracted from magnolia bark, has no diazepam-like side-effects in mice. The Journal of pharmacy and pharmacology, 51(1), 97–103.
Kuribara, H., Kishi, E., Hattori, N., Okada, M., & Maruyama, Y. (2000). The anxiolytic effect of two oriental herbal drugs in Japan attributed to honokiol from magnolia bark. The Journal of pharmacy and pharmacology, 52(11), 1425–1429. https://doi.org/10.1211/0022357001777432
Lloyd & Lloyd (1887). Magnolia. magnolia bark. Magnolia. Magnolia Bark. | Henriette's Herbal Homepage. Retrieved from: https://www.henriettes-herb.com/eclectic/dmna/magnolia.html#glau-bot-hist
Ge, L., Zhang, W., Zhou, G., Ma, B., Mo, Q., Chen, Y., & Wang, Y. (2017). Nine phenylethanoid glycosides from Magnolia officinalis var. biloba fruits and their protective effects against free radical-induced oxidative damage. Scientific reports, 7, 45342. https://doi.org/10.1038/srep45342
Groves, Maria Noel, RH (AHG). (2020). Perky Calm & Alert Backyard Medicinal Herbs. Allenstown, NH. Retrieved from: https://static1.squarespace.com/static/55636a78e4b0658666cb6541/t/5eac6913be207478cdbd2980/1588357463831/Perky+Calm+Alert+Slides.pdf
Ogobuiro I, Gonzales J, Tuma F. (2021) Physiology, Gastrointestinal. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing. https://www.ncbi.nlm.nih.gov/books/NBK537103/
Park, I., Oh, S., Lillehoj, E. P., & Lillehoj, H. S. (2020). Dietary Supplementation With Magnolia Bark Extract Alters Chicken Intestinal Metabolite Levels. Frontiers in veterinary science, 7, 157. https://doi.org/10.3389/fvets.2020.00157
Poivre, M., & Duez, P. (2017). Biological activity and toxicity of the Chinese herb Magnolia officinalis Rehder & E. Wilson (Houpo) and its constituents. Journal of Zhejiang University. Science. B, 18(3), 194–214. https://doi.org/10.1631/jzus.B1600299
Qu, W. M., Yue, X. F., Sun, Y., Fan, K., Chen, C. R., Hou, Y. P., Urade, Y., & Huang, Z. L. (2012). Honokiol promotes non-rapid eye movement sleep via the benzodiazepine site of the GABA(A) receptor in mice. British journal of pharmacology, 167(3), 587–598. https://doi.org/10.1111/j.1476-5381.2012.02010.x
Sarrica, A., Kirika, N., Romeo, M., Salmona, M., & Diomede, L. (2018). Safety and Toxicology of Magnolol and Honokiol. Planta medica, 84(16), 1151–1164. https://doi.org/10.1055/a-0642-1966
Shen, C. C., Ni, C. L., Shen, Y. C., Huang, Y. L., Kuo, C. H., Wu, T. S., & Chen, C. C. (2009). Phenolic constituents from the stem bark of Magnolia officinalis. Journal of natural products, 72(1), 168–171. https://doi.org/10.1021/np800494e
Siegel, R. L., Miller, K. D., & Jemal, A. (2020). Cancer statistics, 2020. CA: a cancer journal for clinicians, 70(1), 7–30. https://doi.org/10.3322/caac.21590
Talbott, S. M., Talbott, J. A., & Pugh, M. (2013). Effect of Magnolia officinalis and Phellodendron amurense (Relora®) on cortisol and psychological mood state in moderately stressed subjects. Journal of the International Society of Sports Nutrition, 10(1), 37. https://doi.org/10.1186/1550-2783-10-37
Tian, H., Zhao, L., Zhang, Q., Zhang, Y., Mao, X., Wang, J., Li, T., Li, J., You, Z., Ruan, Q., & Jiang, L. (2020). The Therapeutic Effects of Magnolia Officinalis Extraction on an Antibiotics-Induced Intestinal Dysbacteriosis in Mice. Current microbiology, 77(9), 2413–2421. https://doi.org/10.1007/s00284-020-02056-6
Tiller J. W. (2013). Depression and anxiety. The Medical journal of Australia, 199(S6), S28–S31. https://doi.org/10.5694/mja12.10628
Walker, J. M., Maitra, A., Walker, J., Ehrnhoefer-Ressler, M. M., Inui, T., & Somoza, V. (2013). Identification of Magnolia officinalis L. bark extract as the most potent anti-inflammatory of four plant extracts. The American journal of Chinese medicine, 41(3), 531–544. https://doi.org/10.1142/S0192415X13500389
Wang, X., Fu, S., Zhang, C., Nie, X., Liao, W., Zhao, M., & Liu, F. (2021). Gastroprotective Effect of Ethanol Extracts from Bark of Magnolia officinalis on Ethanol-Induced Gastric Mucosal Damage in Rats. BioMed research international, 2021, 6688414. https://doi.org/10.1155/2021/6688414
Wang, Y. D., Sun, X. J., Yang, W. J., Li, J., & Yin, J. J. (2018). Magnolol exerts anticancer activity in hepatocellular carcinoma cells through regulating endoplasmic reticulum stress-mediated apoptotic signaling. OncoTargets and therapy, 11, 5219–5226. https://doi.org/10.2147/OTT.S168887
Wolf, I., O'Kelly, J., Wakimoto, N., Nguyen, A., Amblard, F., Karlan, B. Y., Arbiser, J. L., & Koeffler, H. P. (2007). Honokiol, a natural biphenyl, inhibits in vitro and in vivo growth of breast cancer through induction of apoptosis and cell cycle arrest. International journal of oncology, 30(6), 1529–1537.
Worley S. L. (2018). The Extraordinary Importance of Sleep: The Detrimental Effects of Inadequate Sleep on Health and Public Safety Drive an Explosion of Sleep Research. P & T : a peer-reviewed journal for formulary management, 43(12), 758–763.
Zhang, W. W., Li, Y., Wang, X. Q., Tian, F., Cao, H., Wang, M. W., & Sun, Q. S. (2005). Effects of magnolol and honokiol derived from traditional Chinese herbal remedies on gastrointestinal movement. World journal of gastroenterology, 11(28), 4414–4418. https://doi.org/10.3748/wjg.v11.i28.4414
Zhang, Y. J., Li, S., Gan, R. Y., Zhou, T., Xu, D. P., & Li, H. B. (2015). Impacts of gut bacteria on human health and diseases. International journal of molecular sciences, 16(4), 7493–7519. https://doi.org/10.3390/ijms16047493