Herbal medicine, also called botanical medicine or phytomedicine, is the practice of using one or more parts of a plant—its seeds, berries, roots, leaves, bark, or flowers—to relieve physical and psychological problems, prevent disease, or just improve overall health and vitality. Although many modern drugs were originally developed from plants, they are based on isolated chemicals, while plants comprise myriad active components, which work together to create their medicinal actions. Herbs have a long history of use and, when used properly, are safe and powerful medicines.
The History of Herbal Healing
Long before doctors in lab coats started writing prescriptions—in fact, even before human beings started writing at all—herbs were being used as medicine. Herbal medicine has prehistoric origins, and it continues today in virtually every culture in the world.
Herbal medicine dates back thousands of years, although no one is exactly sure when the first human used an herb to treat a health woe. In the American Southwest, for example, researchers have found human genetic material on hunks (called quids) of the herb yucca, which were chewed and spit out like a kind of ancient chewing gum. The quids are between 800 and 2,400 years old.
The World Health Organization reports that roughly 25 percent of all modern medicines are made from plants that came straight out of traditional medicine. For example, two South American species, the chinchona tree (Chinchona officinalis) and the coca plant (Erythroxylum coca), have given us the antimalaria drug quinine and several types of anesthetics.
In Europe, researchers discovered what looks to be herbal remedies on the body of the infamous “Ice Man,” the 3,000-year-old mummy discovered in the early 1990s in the Italian Alps. Researchers found walnut-sized lumps of birch fungus, which has laxative and antibiotic properties, on his body. An autopsy revealed that the man had been suffering from an infestation of parasitic whipworms, leading the experts to guess that he had most likely been treating them with measured doses of the medicine.
As civilizations rose up around the world, so did herbal medicine. And although some of the ancients’ remedies have fallen by the wayside, most are still popular.
The Egyptian priest and physician Imhotep, who lived around 2600 B.c. and is often credited with the earliest medical writings, described the diagnoses and treatments—many of them herbal—of more than 200 diseases.
In China, the emperor Shen Nung, in 2735 B.c., wrote what is generally believed to be the earliest treatise on herbs, discussing hundreds of medicinal plants that are still in use. And in India, a manuscript from around 2000 B.c. mentions the herbs cinnamon, ginger, and sandalwood as ingredients in several medical preparations.
To avoid confusion (and language barriers), an herb is usually identified by its common name as well as its scientific (botanical) name, which comprises the Latin words for the plant’s genus and species. That way, if you’re looking for chamomile, you’ll know if you’re getting the popular German or Hungarian variety (Matricaria recutita) or the less common Roman or English variety (Chamaemelum nobile).
Principles and Traditions
No matter where in the world it originated, any school of traditional herbal medicine is based on a simple concept: that herbal remedies can be used to create—or re-create—a state of health within the body. Herbal healers categorize diseases according to a specific set of symptoms, then use their remedies to restore the patient to the state he was in before the disease struck.
A “Humor"ous Approach
Western herbalism evolved from the Greeks, who in turn were strongly influenced by Egyptian and Middle Eastern civilizations. The Greek system uses a system of “humors,” which are tied to four dynamic elements (air, earth, water, and fire). The Greeks believed that diseases were caused by an imbalance of these humors. The humors were part of an individual’s nature and weren’t necessarily good or bad. But if they got out of balance, illness would ensue.
The theory of the humors is similar to the basic beliefs of Traditional Chinese Medicine (TCM) and Ayurvedic medicine, which originated in India at roughly the same time. In Ayurveda, for example, there are three doshas,or body types, which correspond to the natural world and also reflect an individual’s innate nature.
Actions Speak Louder
Traditional herbal medicine is also organized around each herb’s physiological actions—what it does in the body. (Not surprisingly, modern herbalists do the same thing.) For example, the Greeks categorized their herbs as warming, drying, cooling, binding, and relaxing. The Chinese have classifications like purging, lubricating, stimulating, clearing, and calming. Not too far from our modern-day classifications, which you’ll see as you walk down the aisle of any drug store: expectorants, laxatives, sedatives, stimulants, and so on.
And while some consumers might scoff at some traditional terminology, modern research shows that, for the most part, the ancients had it right. In fact, of the 100-plus known medicinal plant compounds used today, roughly 80 percent are used for purposes that are identical or very close to their traditional use.
One of the most powerful chemotherapy agents existing today comes from the Pacific yew (Taxus brevifolia). Yew trees were routinely discarded in logging enterprises until 1967, when somebody discovered a compound called taxol that could inhibit the division of cancerous cells. Today, taxol is used to treat breast, ovarian, and lung cancer.
The Chemistry of Plants
Although people have been using herbs for centuries, we don’t know a whole lot about the pharmacology, or chemical makeup, of many of them. Unlike pharmaceuticals—drugs created in a lab from a precise chemical recipe—herbs are often chemical mysteries.
Unraveling the Mysteries
In recent years, scientists have been deconstructing herbs to determine the chemical compounds—called phytochemicals—behind their actions.
For example, researchers have determined that garlic (Allium sativum) owes much of its antibacterial and cholesterol-lowering action to a phyto-chemical called allicin. Ginger (Zingiber officinale) apparently gets its stomach-settling powers from two chemicals, 6-gingerol and gingerdione. And cayenne peppers (Capsicum annuum, C. frutescens) contain capsaicin, which dulls pain and produces a warming sensation.
Primary and Secondary
In most cases, the compounds that are so helpful to humans are actually secondary to the plant’s survival. The most important things, at least as far as the plant is concerned, are the primary constituents, which are used in the plant’s primary metabolic processes (like photosynthesis) and include things like sugars and chlorophyll.
Secondary constituents are things that the plant developed over the course of its evolution to defend itself against animals, insects, disease, or environmental stresses such as changes in temperature or water levels. Quite often these compounds—which include vitamins, minerals, essential oils, and phytochemicals—are key to both the plant’s viability and its bioactivity (the effect it has on another living organism or tissue).
According to the latest estimates, there are 122 scientifically identified plant compounds being used as drugs throughout the world, which are drawn from just 94 plant species. With several thousand known medicinal plants now in use, scientists still have quite a few more chemicals to name.
Luckily, the chemicals that make a plant unappealing to microbes can serve as antimicrobial agents in humans, too. And the neurotoxic chemicals that a plant uses to defend itself against foraging deer can work as sedatives, muscle relaxants, or anesthetics in people.
Most of the secondary constituents in plants can be lumped into three categories: terpenoids, alkaloids, and polyphenols.
Many terpenoids are either toxic or just unappetizing to grazing animals; others make a plant more appealing to pollinating insects. Feverfew (Tanacetum parthenium) and chamomile (Matricaria recutita) contain medicinal terpenoids.
Alkaloids can have potent medicinal activity. Examples are nitrogen, caffeine, quinine, morphine, and nicotine. The Chinese herb ma huang (Ephedra sinica) contains the alkaloid ephedrine. Cocaine is found in the leaves of the coca shrub (Erythroxylum coca).
Polyphenols include tannins and flavonoids. Tannins are astringent chemicals (once used to tan animal hides) found in the seeds and stems of grapes (Vitis vinifera), the leaves and bark of trees or shrubs like witch hazel (Hamamelis virginiana), and tea leaves (Camellia sinensis). Flavonoids are a broad class of compounds that act as antioxidants (agents that counteract the process of oxidation, which can damage cells and trigger disease). They are found in ginkgo (Ginkgo biloba), hawthorn (Crataegus monogyna, C. oxyacantha), and milk thistle (Silybum marianum), among others. Iso-flavones are one type of flavonoid that act as phytoestrogens (plant compounds that mimic the effects of estrogen in the body). Isoflavones are found in soybeans (Glycine max).
The Sum Versus the Whole
But while scientists have identified the active constituents in many herbs, many more remain a mystery, in part because the chemicals in the plant appear to work synergistically instead of individually.
That means that, in most cases, we don’t know which ingredient in a plant is causing a therapeutic effect, or if that ingredient is acting alone or in combination with other ingredients. Moreover, because it’s a natural thing, an herb’s biochemical composition is inherently variable and can change from year to year or crop to crop.
The Evolution of Herbal Medicine
As early civilizations developed, they slowly left behind the hunting-and-gathering routine in favor of cultivation, building settlements, and developing a more cohesive social structure. In virtually every part of the world, herbs were part of the arsenal of healers, who combined spiritual and religious elements in their medicine.
Before test tubes and research labs, herbalists around the world used a decidedly nonscientific method called “the doctrine of signatures,” which held that plants (or plant parts) that looked like a human body part would benefit that part. Thus, medieval healers recommended the phallus-shaped mandrake (Mandragora officinarum) root for impotence and the brainy-looking walnut (Juglans regia) for mental disorders.
As people began to grow and gather herbs, they learned, through experience, trial-and-error, and plain old luck, which plants could be useful and which ought to be avoided.
To help them understand the complexities of their world, primitive people came up with a pantheon of gods, spirits, and supernatural forces, many of which were directly tied to the natural world. In time, people around the world began to realize that sickness and disease (or health and vitality, for that matter) were created by natural and not supernatural processes. At that point, the healing profession split into separate factions, with the physician on one side and the priest on the other.
In the early nineteenth century, scientists began extracting and modifying the active ingredients from plants and transforming those ingredients into synthetic drugs. Gradually, medicine—and popular tastes—shifted from herbals to pharmaceuticals.
In 1820, the U.S. Pharmacopeia (USP) published its first standards compendium, then consisting of only natural medicines. But things were changing, and in the United States and many other Western countries, herbal medicine was quickly moving from its place as the primary health care system to a type of supplemental care.
Many countries, including India and Germany, now consider many herbs to be medicines (and therefore regulate them as drugs). According to the latest report from the World Health Organization (WHO), ninety-two countries have an official registration system for herbal medicines, and seventeen of them have more than 1,000 herbal medicines registered.
In the United States, herbs have been regulated by the Food and Drug Administration (FDA) and its predecessor agencies for the past 100 years. In 1994, the government passed the Dietary Supplement Health and Education Act (DSHEA), which classified nearly all herbal products as dietary supplements—to be handled like foods, not medicines.
How Herbs Can Complement Conventional Medicine
Until recently, herbal medicine was practiced outside of conventional medicine, the system of pharmaceuticals and surgery that most Americans think of when they think of health care. But these days, herbalism is going mainstream, as more and more people catch on to its benefits—and more and more studies show the power of plants in treating and preventing disease. The various schools of complementary and alternative treatments (including herbal medicine) are known collectively as CAM. Combining CAM with conventional medicine is known as integrative medicine.
Although you should always consult a medical professional in the case of a serious injury or chronic disease, you can use herbs to treat many minor health problems and to maintain your overall health. And with your doctor’s approval, you also can add herbs to many conventional medical treatments. In many cases, you don’t need the firepower that pharmaceutical drugs provide; the gentler properties of herbs will serve you much better.
Indeed, one of the biggest selling points for many MDs is the disease-preventing power that many herbs have. Research continues to show that various preventive measures—getting enough exercise, eating healthy foods, etc.—can stave off many diseases, and herbs with nutritional value fit the bill nicely. Consider the case of antioxidants, a class of plant chemicals that prevent cell damage caused by reactive molecules known as free radicals. Research shows certain micronutrients—most notably vitamins C and E and the mineral selenium—have high antioxidant levels. But many medicinal and culinary herbs are also antioxidant powerhouses. Some of the biggest include tea (Camellia sinensis), elderberry (Sambucus nigra), rosemary (Rosmarinus officinalis), and turmeric (Curcuma longa).
Herbs also can work as complementary or adjunct therapies, enhancing the effects of conventional drugs and/or treatments and offsetting any side effects they might produce.
For example, ginger (Zingiber officinale) can relieve post-operative and chemotherapy-induced nausea.
Tea (Camellia sinensis) is the world’s second most popular beverage (behind water). It comes in three varieties: green, which is unfermented, oolong, which is partially fermented, and black, which is completely fermented. All are good for you, but green tea seems to have the highest levels of polyphenols, the phytochemicals credited with many of tea’s benefits.
In other cases, herbs can accentuate the benefits of conventional treatments. For example, cancer patients who take cordyceps mushrooms (Cordyceps sinensis) after chemotherapy treatments seem to get a boost in cellular immunity. And a new study shows that combining chemotherapy with the Chinese herb astragalus (Astragalus membranaceus) works better than chemotherapy alone at stimulating the patient’s immune system. Other studies have shown that the turkey tail, or coriolus, mushroom (Trametes versicolor, Coriolus versicolor) can significantly prolong cancer survival when taken in conjunction with chemotherapy or radiation treatment.
Other Healing (Herbal) Modalities
Many health care professionals, including naturopathic physicians, chiropractors, and practitioners of Traditional Chinese Medicine (TCM) and Ayurveda (the ancient system of health care of India), use herbs and herbal formulations. Herbs also play a part in other types of natural health care, including aromatherapy and homeopathy.
Aromatherapy is the practice of using aromatic plants to treat various conditions and maintain overall health. It dates back to the ancient Egyptians, Greeks, and Romans, who used fragrant plant oils in healing baths and therapeutic massage.
Legend has it that modern “aromatherapy” was born in the 1920s, when a French chemist inadvertently discovered the power of plant oils when he burned his hand and plunged it into the nearest cool liquid he could find: a vat of lavender oil. The pain was relieved and the burn healed remarkably well, with no inflammation, blistering, or scarring.
Modern aromatherapy uses essential oils, which are volatile liquids distilled in a way that selects miniscule molecules and leaves behind heavier plant waxes, oils, and other materials. Thus, essential oils are incredibly potent and deliver what the experts consider to be the “essential” parts of the plant: its phytochemicals and its scent.
Today, aromatherapy is practiced by aerial diffusion, direct inhalation, and topical application (via massage). Experts theorize that it works in two ways. The first is through aroma, which moves through the olfactory system to stimulate limbic (emotional) centers of the brain. The other is through a direct pharmacological effect: The oils’ beneficial compounds are delivered via the skin or mucous membranes.
Homeopathy is a school of natural medicine developed in eighteenth-century Germany and based on a simple theory, called “the law of similars,” which holds that a substance that produces symptoms in a healthy person will cure a sick person showing the same symptoms (the word homeopathy comes from two Greek words: homoios, meaning “similar,” and pathos, meaning “sickness”). In shorthand: “Like cures like."
The “like cures like” theory of homeopathy is not as far-out as it might seem. It’s actually rooted in ancient Greek tradition, where it was called similia similibus curentur, or the “similia principle.” Centuries before homeopathy was developed, Hippocrates had found that he could treat recurrent vomiting with an emetic herb (one that would ordinarily be used to induce vomiting).
The other basic tenet of homeopathy is the law of potentization, which holds that the lower the dose of a medicine, the greater its potency—and effect. Homeopathic remedies are sold according to their potency: The ingredients are diluted, then shaken over and over again (in a process called succussion) until there are only miniscule amounts of the original compound (or none at all) remaining.
Many homeopathic remedies are derived from plants, and others use minerals and animal parts.
Flower essences, also known as flower remedies, were developed in the early twentieth century by British physician and homeopath Edward Bach (pronounced “Batch”), who felt that many, if not all, of the physical problems people face are tied to our emotional state. According to Bach, you could be healthy only after you cast out the negative emotions—fear, worry, animosity, and indecision—that destroy your body’s equilibrium.
The most famous flower essence product is known as “five-flower remedy” and sold under various names (the most popular of which is Bach’s Rescue Remedy). It’s a premixed combination of the essences of cherry plum, clematis, impatiens, rock rose, and star of Bethlehem, used to relieve the stress caused by travel, injury, or an upcoming event.
Bach came up with thirty-eight flower remedies, all based on the homeopathic principles of similarity and potency. He chose flowers that reflect the condition that needs attention (the aspen tree, which seems to quake before a storm, gives us the remedy for anxiety and apprehension, while impatiens is prescribed for individuals who are hasty and—you guessed it—impatient).
Herbs can also be incorporated into the menu, and they deliver their benefits as easily when they’re served as a food as when they’re taken as medicine. Edible herbs with proven health benefits are called functional foods.
Several varieties of edible mushrooms are considered medicinal. In particular, reishi (Ganoderma lucidum), shiitake (Lentinula edodes), and maitake (Grifola frondosa) appear to support immunity, fight infection, and even offer protection against diabetes, heart disease, and cancer. Mushrooms contain carbohydrates called polysaccharides, which stimulate the immune system. Some specifically stimulate the “natural killer” cells, which can recognize and attack cancer cells.
Many types of mushrooms are also loaded with antioxidants, and studies show that some varieties have more antioxidant power than brightly colored vegetables like carrots and tomatoes.
Studies suggest that other polysaccharides may help protect bone marrow from the effects of chemotherapy and enhance its ability to fight cancer. Research also shows that mushrooms typically contain large levels of a material called chitin, which can lower cholesterol.
It’s not just the gourmet fungi that have benefits: Inedible mushrooms can pack a real medicinal punch, too. For instance, a recent study found that dried extracts of the cordyceps mushroom (Cordyceps sinensis), a mainstay of Chinese medicine, appear to increase aerobic fitness in middle-aged adults.
Eating soybeans (or soy-based products like tofu and tempeh) has been proven to improve your health in many ways. The isoflavones in soy have proven anti-inflammatory, pain-relieving, and cancer-fighting benefits; eating soy has also been linked to a reduction of menopausal symptoms such as hot flashes.
Garlic and Onions
They might wreak havoc on your breath, but these two herbs—actually part of the same genus of plants—can do wonders for your health.
In order to reap the benefits of fresh garlic, you’ve got to eat it raw, as any cooking dramatically reduces its disease-fighting activity. And don’t eat the cloves whole—garlic’s active constituent, allicin, is created when the enzyme allinase is released by chopping or crushing the cloves and exposing them to air for more than ten minutes.
Studies show that both onions (Allium cepa) and garlic (Allium sativum) contain sulfur compounds that can help with diabetes, heart disease, and cancer. In other research, garlic has been shown to prevent artery damage caused by LDL—or “bad”—cholesterol.
Ginger (Zingiber officinale) is a healthy addition to many dishes, whether you use the root fresh or dried and powdered. Studies show that it can reduce many types of pain and inflammation, including the type associated with rheumatoid and osteoarthritis.
Ginger can also relieve nausea and vomiting from many causes, including seasickness, anesthesia, and pregnancy.
Eating dark chocolate made from Theobroma cacao has proven health benefits, including lowering blood pressure, improving cholesterol levels, fighting age-related cognitive decline, preventing blood clots during prolonged travel, and even reducing the risk of certain cancers. And drinking cocoa helps, too. A new study found that older men (aged sixty-five to eighty-four) who consumed the most cocoa had half the risk of dying during the study’s fifteen-year span than those who got none.
Why Herbal Medicine Works
Herbalism has a long history of efficacy and safety, and has earned its place in the pantheon of modern medicine. Here’s why:
Many herbal remedies have hundreds, if not thousands, of years behind them. And while pharmaceuticals are often tested for short-term safety only, drugs that have been used as folk medicine over millennia have been proven safe and effective over the long term.
Moreover, herbs are generally used for more than one condition, as opposed to drugs, most of which are used for a single purpose.
Of course, there are exceptions to this rule, but generally speaking, herbs are much easier on your body than their pharmaceutical counterparts. Consider the drugs used for depression: Side effects for popular antidepressants like Prozac and Celexa include impaired thinking, sexual problems, insomnia, and headaches. In contrast, herbal remedies like lemon balm (Melissa officinalis), rhodiola (Rhodiola rosea), and Saint John’s wort (Hypericum perforatum)fight depression with relatively few unwanted effects.
Traditional and herbal medicine is the main type of health care for most of the planet’s population, and the use of complementary and alternative medicine is rising throughout the world. In some countries, up to 80 percent of people consider herbs to be their primary method of staying well.
The basic tenet of herbalism—and all schools of natural medicine—is that it’s better to work for optimal health all the time than to wait until disease strikes. For example, herbalists have long recommended herbs like American ginseng (Panax quinquefolius) to help stave off the common cold. And a new study shows that consuming dried extracts of the herb reduces both the incidence and the severity of colds.
Additionally, herbs contain many constituents that work together to alleviate specific symptoms—and to address an underlying problem and strengthen the overall functioning of a particular organ or system. And herbs are often used together to foster health.
For example, a multiherb combination containing licorice (Glycyrrhiza glabra), chamomile (Matricaria recutita), peppermint (Mentha x piperita), and lemon balm (Melissa officinalis) is used to treat heartburn, nausea, and vomiting—and strengthen the digestive system.
Lastly, it’s a rare herb that’s used to treat just one body part or system. Most treat several things at once—and new research is backing up that whole-body approach. Consider green tea (Camellia sinensis): It’s been associated with head-to-toe benefits ranging from reduced cognitive decline, lowered incidence of heart disease and many cancers, and improvements in overall mortality rates. It’s used successfully to fight oral bacteria, allergies, bladder infections, and genital warts—and even appears effective against antibiotic-resistant “superbugs.” Try to find a drug or therapy in conventional medicine that can make those claims.