Plants and Your Health: The ABCs of Herbal Medicine

By Larry Rettig (LarryR) on October 6, 2010

Did you know that chimpanzees, our closest living relatives in the animal kingdom, actually use plants in the wild to medicate themselves? Incredible, but true.

Gardening picture

Richard Wrangham, a Harvard professor who does research at the Gombe National Park in Tanzania, has actually documented the medicinal use of young Aspilia leaves by the chimpanzees he studied.  He and his fellow researchers observed chimps "wadding up the leaves whole, then holding them under their tongue for a while, then swallowing without chewing.  The leaves passed through the intestines undigested and intact in the stools."  Occasionally throughout the meal the chimps would make sour faces. "Apparently it was no tasty treat," he concluded in his research report.

                 © Elisa Salengue and Daniel Saraiva
Aspilia spp.

Wrangham was quite intrigued by this behavior and sent samples of the plant for analysis to a biochemist at the University of California in Irvine.  The result showed that the leaves contain thiarubrine-A, an oil already known to be a very effective toxin against fungi, bacteria, and parasitic nematodes.  As Wrangham noted earlier, the chimps much preferred the youngest Aspilia leaves over older ones.  The analysis showed that the younger the leaves were, the  richer they were in the bioactive oil.  It was also quite significant that all the chimps kept the "drug" under their tongues before gulping it down.  Dense with minute blood vessels, the tongue is able to absorb a substance held there, thus bypassing the digestive juices of the stomach and going directly into the circulatory system.  For more on this chimp behavior, see The Medicinal Use of Plants by Chimpanzees in the Wild, by Michael A. Huffman.


So Where are the ABCs?

This is, after all, an article about the human use of medicinal herbs, not one about chimps.  I simply wanted to demonstrate that if chimps can practice herbal medicine successfully, then it certainly is no stretch to acknowledge that humans do, too.  And we certainly do.  Just think about all the medicine men on the continent of Africa, those in Native American tribes, and even the pioneers that settled our country.  If you're interested in pursuing the use of medicinal herbs in the U.S. and want a good read in the bargain, I highly recommend Sharon Brown's Aunt Bett stories.  They offer a treasure trove of medicinal practices in Appalachia.  You can find them here.

The First ABC

I've often read that claims about one herbal medicine or another have not been substantiated.  Indeed, some assert that all claims about the efficacy of herbal medicines are false.  So I set about to find out what is known scientifically about medicinal plants and their healing properties.  By great good fortune, I stumbled upon the American Botanical Council (ABC).  The ABC is a nonprofit educational/research organization that provides information about and promotes the safe and effective use of medicinal plants and phytomedicines.  (Phytomedicines incorporate plant extracts, but mix them with other substances to produce a beneficial effect.)

The ABC's mission is to "provide education using science-based...information to promote responsible use of herbal medicine - serving the public, researchers, educators, healthcare professionals, industry and media."  Part of that mission is to collect all published scientific studies dealing with the efficacy of herbal medicines from around the world--a monumental task, not only because there are so many clinical trials, but also because many of them have to be translated into English.  Currently there are 277 plants listed, some with over 50 clinical trials.  I gladly paid the $9.95 it cost me to access the scientific article database for 48 hours.

The Second ABC

The time and space required to list all 277 plants with their accompanying articles and their scientific results doesn't allow me to show you the entire body of science regarding the effectiveness of the plants listed, but let me at least give you a sampling.  In the table below, I've listed the studies alphabetically, according to plant.  From articles indexed under each letter of the alphabet, I selected one study per letter, more or less at random.

Plant Name
   Number of Clinical Trials                       
Examples of Positive Results  

Aloe vera


 Aloe vera cream more effective than triamcinolone acetonide, commonly used in mild to moderate psoriasis; also effective in treating dermatitis, lichen planus, frostbite, burns, wounds, and some inflammations

Bacopa monnieri


 Shows positive results for enhancing cognitive performance in elderly; significant improvement in patients with hepatic encephalopathy; significant positive effect on a test for retention of new information in 76 adults

Crocus sativus


 Therapeutic effect in adults 55 years of age or older with mild to moderate Alzheimers; definite anti-depressant effect in depressed adults
 Dryopteris spp. 1  Cure achieved in 25 out of 29 cases of taeniasis (tapeworm)
 Epimedium spp. 6  Improved quality of life in patients with chronic renal failure; relieved symptoms in 97% of patients with allergic rhinitis
 Foeniculum vulgare 5  Eliminated cholic in 65% of test group; effectively treated primary dysmenorrhoea in 60 female patients
 Gymnema sylvestre 6  Reduced body weight and body mass index (BMI) in 60 moderately obese patients
 Harpagophylum procumbens 14  Very effective in the treatment of lower back pain and arthrosis of the hip and knee
 Inula spp. 2  Effective treatment for nausea and vomiting in chemotherapy patients
 Juniperus spp. 5  Statistically significant improvement of symptoms in patients with allergic rhinitis
 Kadsura spp. and Kochia  scoparia 0  Only two plants listed under "K"; no human trials
 Lavandula spp. 35  Effective treatment of agitated patients with Alzheimers; reduced anxiety and improved mood of 200 patients while waiting for dental treatment; improved mood, made people feel more relaxed, and allowed them to perform math computation faster
 Mahonia aquifolium 4  Effective in the management of mild to moderate psoriasis in 200 subjects
 Nigella sativa 4  Effective in treatment of 20 epileptic children with refractory seizures; improvement in 152 patients with allergic rhinitis, bronchial asthma, and eczema
 Ocimum spp. 5  Effective treatment with a polyherbal preparation (containing Ocimum) of 36 HIV-infected patients, showing a decreased mean viral load and producing good symptomatic improvement and an increase in the mean CD4 cell count
 Passiflora alata 6  Passiflora extract plus clonidine effective in detoxification of 65 outpatient opiate addicts
 Quassia spp. 2  Effective in treatment of head lice
 Rhodea rosea 14  Pronounced anti-fatigue effect; effective in treatment of mild to moderate depression
 Sambucus nigra 14  Effective treatment of influenza A and B in 60 patients; Quality of life significantly improved for 80 participants who had weight, blood pressure, physical, or mental issues
 Thymus vulgaris 7  Alleviated cough associated with common cold and bronchitis; shortened duration of acute bronchitis
 Uncaria tomentosa 5  Effective in treatment of vascular dementia; effective in treatment of osteoarthritis; possesses anti-inflammatory properties
 Vaccinium macrocarpon 12  Found to limit bacterial adhesion activity in urine; promotes urinary tract health
 Withania somnifera 4  Provides relief in cases of osteoarthritic knees
 Xylopia aromatica/X. aethiopica 1  Lowers interocular pressure
 Yucca schidigera/Y. filamentosa 3  Lowers total cholesterol levels and LDL cholesterol
 Zingiber officinal


 Considerable antioxident, anti-inflammatory, antiplatelet, and hypolipidemic effect

I certainly didn't expect to find such a large number of clinical trials nor such a large number of plants in the database.  Granted, as clinical trials go, these involved relatively few subjects.  More research must be done before the scientific world is satisfied that any given plant substance is truly efficacious.  The fact remains, however, that patients in these trials found relief and even cures for their ailments.  I look forward to the results of continued research and further clinical trials.

Endnote:  When I began to prepare the table above, just as I was entering the information for Aloe vera, I noticed that the fire in the living room fireplace was almost out.  I got up to stoke it and, in the process, accidentally burned my left knee.  Although quite painful, I decided that it didn't require a doctor's care--completely disregarding my own admonition above--and headed straight for the Aloe vera plant on a windowsill in the kitchen. I cut off a small piece, slit it open, and rubbed the cooling gel on the burn.  I reapplied gel three or four more times, waiting each time until the application had dried before applying more.  I expected a large blister, but none developed.  Within three hours the pain was completely gone.  My own mini clinical trial was a complete success!


 Aloe image courtesy of Wikimedia

About Larry Rettig
"An enthusiastic gardener for over 50 years, my first plant was a potted Ponderosa Lemon tree ordered from a comic book ad at age 15. I still have it, and it’s still bearing lemons! My wife and I garden on 3/4 of an acre, both flowers and vegetables. Our garden, named Cottage-in-the-Meadow Gardens, is private and is listed with the Smithsonian Institution in its Archives of American Gardens. It is also on the National Register of Historic Places. We garden organically and no-till. Our vegetable garden contains a seed bank of vegetables brought to this country from Germany in the mid-1800s by my ancestors. My latest book, Gardening the Amana Way, is available at

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Comments and discussion:
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13 Reasons For Aloe Plant Turning Brown And Wilting Bhawana Aug 1, 2021 11:30 AM 0
A subject close to my heart... Sharon Jul 18, 2013 10:03 AM 6

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