The Truth About Herbal Medicine

Use this guide to become a savvy natural-health consumer, and learn how to decipher the safety of herbal medicine for yourself.

Truth About Herbal Medicine

Learn the truth about herbal medicines to begin understanding herb safety.

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BREAKING NEWS: Is chamomile deadly? Why a recent study has experts wondering whether that cup of tea in your hand might just be a death sentence. Follow-up at 10 o’clock.

These days, I watch the news looking for scare tactics like this. It can sometimes seem as if the media is actively trying to discredit herbal medicine. Because the average consumer doesn’t know the full story behind each study, and often doesn’t have the time, inclination or tools to analyze the information themselves, they ditch the herbal option thinking, “better safe than sorry”—even though they may be skeptical that chamomile is dangerous. This is unfortunate when we consider the boon to wellness herbal medicines can be, especially when our mainstream medical system focuses more on treating symptoms than on promoting health.

The Herbal Environment

We herbal health advocates are in a sticky place in the U.S. The mainstream medical community often says herbal and botanical medicines are ineffective, while simultaneously saying herbal medicines are dangerous. The idea that the mainstream media may have motivation to discredit nonconventional medicine is one backed by research. As Mark Blumenthal, executive director of the American Botanical Council, stated in his 2013 speech, “Health Benefits of Popular Herbal Supplements in the U.S. Market”, “If you look at medical journals, they too are subject to bias. According to a pilot trial of 11 top journals, the more advertising in a medical journal over a one-year period from pharmaceutical drug advertising, the less coverage there was on herbs and dietary supplements in general—and what coverage there was tended to be negative about safety and efficacy.”

Along with creating a confusing environment for the average consumer, this also makes legislation governing the sale of herbal products a bit schizophrenic. It makes it possible for sketchy, and often dangerous, “natural” diet supplements to be sold by everyone from TV personalities to the corner drugstore. Then, when these supplements—which promise to help someone lose 50 pounds in two weeks with no effort—inevitably harm people, it casts doubt on natural products as a whole.

At Mockingbird Meadows Herbal Health Farm, where we teach people how to grow, prepare and use medicinal herbal applications, we advise our students to make the purest product they can in the cleanest manner possible.

Personal Wellness

Our current health-care system is unsustainable. Rather than focusing on common-sense, time-honored ways to improve our health and wellness, we live in unhealthful ways and then expect pharmaceutical medicine to undo the damage we’ve done to our bodies.

It’s inappropriate to expect Western medicine to do more than the heroic, life-saving medicine it’s very talented at performing. To maintain health, we can turn back to simple methods. As we take the load of daily wellness off our health-care system, we will increasingly turn to nature—meaning high-quality foods and well-researched herbal medicine, along with healthful habits such as exercising daily and reducing stress. That means we’ll need to know how to demand and discern quality in our foods and herbs.

The three main areas that follow are where we consumers need to equip ourselves with good tools of discernment. 

New Medical Studies

Although studies designed to test safety and confirm effectiveness of herbal medicines are abundant, they are frequently underreported or reported irresponsibly. This means we must educate ourselves beyond the headlines.

It can be difficult to find reliable reporting on herbal science, but the good news is that the studies are happening. “People say there’s not enough science about herbs; I’ve heard some physicians say there’s no science about herbs,” Blumenthal says. “If you look at the data in the last 30 years, the number of studies on herbal preparation and isolated compounds have gone from 739 papers in 1977 to over 6,000 in 2007.”

Comfrey (Symphytum species) makes a good case study. Some years ago, a study cast doubt on herbs that contain pyrrolizidine alkaloids (PAs)—in particular comfrey. As a result, comfrey is not on the FDA’s generally recognized as safe (GRAS) list. The herbal community self-regulates by this list, agreeing to refrain from selling products containing comfrey that are intended for internal consumption. This is why you won’t see it in a cough syrup in the store.

I use comfrey in many of my classes as an illustration of how to break down a study and make personal health-care decisions. When confronted with a breaking news bulletin about a study, it’s important to ask the following:

• Who funded the research and what was their motivation?
• What are the methods of the research?
• What are the applications to human use?
• Was this trial on humans or animals?
• What is the historical information on the herb?
• Have there ever been any written indications of the same issue?
• What are your own personal decisions after reading the research, and what are the individual health concerns that must be factored into your decision?

Using these standards, let’s look at comfrey more closely. Comfrey is a common name for a group of nine species of perennial plants in the genus Symphytum. Some of these species, including S. officinale, are known to contain pyrrolizidine alkaloids. Some members of the genus contain very small amounts or none at all, for example S. × uplandicum, believed to be the native species in the United States. Humans have a long written history of using plants from this genus for medicine without a cause for concern.

The study that started the controversy was done on 21-week-old rats, which don’t have the same reaction to PAs as humans do. The rats were injected with a high dose of one of the isolated PAs (symphytine) rather than a dilution of the whole plant. When you isolate a compound within a plant, you do not get the thousands of other chemicals that often act as a buffer for that compound. At any rate, we don’t inject comfrey, we eat it. When it is injected, the effect of the compound is concentrated. A small number of the rats in the study subsequently developed liver cancer. Were we to duplicate the same level of PA consumption used in the study in our daily diet, we would need to consume between three-quarters of a pound and 114 pounds a day for at least 21 weeks. Given that the average amount in a therapeutic dose is less than a quarter of an ounce, this is possible but highly unreasonable.

“The comfrey incident might have looked different if it had been put into context of a toxicity scale,” Blumenthal says. “One such scale is the HERP (human exposure/rodent potency) index, which classifies the cancer-causing potentials of various substances. Extrapolating from the HERP index, former U.S. Department of Agriculture botanist James Duke calculates that less than one-fifth of an ounce of brown mustard is twice as cancer-causing as comfrey tea, which has roughly the same cancer-causing potential as a peanut butter sandwich. Wine is 144 times more cancer-causing than an equal amount of comfrey tea.”

Finally, there is no information in the historic data of problems with the use of comfrey and there are no cases of veno-occlusive liver disease that can be definitively traced to its ingestion.

Many people continue to use comfrey internally without concern. In the U.S., if you are wild-harvesting or growing your own, you are very likely getting S. × uplandica anyway—which doesn’t contain the potentially concerning PAs. In all such cases, you must balance the newer scientific findings on each herb with your own internal voice. You may see no logical reason to avoid eating comfrey, but a family history of liver dysfunction makes you think twice. You may be ready to use it in your tea but have a niggling doubt in your gut. If so, comfrey isn’t right for you. You can use comfrey externally without concern and avoid the internal controversy altogether. In the end, many other herbs may work as well or better for your particular body chemistry.

Anytime you decide a “banned” herb is right for you, be sure to let your health-care team know of your decision so they can offer you their perspectives and help you avoid any future negative interactions or overuse.

Personal Medicine

We must all be the arbiters of our own health. Regardless of any study or other people’s experiences, not every herb is right for every person. Our bodies are all unique and therefore the ailments that befall us require specialized treatment.

Valerian may be the perfect herb for you to combat your insomnia. Unfortunately, my husband is one of a small percentage of people for whom valerian is a stimulant. Instead of sleeping, when I once gave him valerian tincture before bed, he stayed up most of the night organizing my kitchen cupboards. Nice for me; bad for him.

For nearly any health ailment, there are specific herbs practitioners find to be successful again and again throughout the history of their use. There is also a long list of other herbs that might work just as well. If you try an herb that everyone suggests as “specific” for your problem and it fails, don’t be discouraged from using natural remedies. Instead, try a different herb. My husband did very well with hops instead of valerian.


Finally, when it comes to herbal preparations, quality is of utmost importance. Adulteration can mean that the herb in question is being mixed with something else at the point of processing. It’s fairly common in unscrupulous facilities to “cut” the more expensive herb with a more-common plant as filler. Profits go up, and sadly sometimes so do the incidences of toxicity. In many cases we are able to analyze the herb and its constituents and show that none of the chemicals found normally in the plant can cause the damage in question.

Kava (Piper methysticum) is a recent example of this problem. A decade ago, concerns surfaced over the possible hepatotoxicity of the herb, which is traditionally used to treat anxiety and insomnia. In the case against kava, it was believed that there were 50 to 100 possible incidences of toxicity from the plant. This equates to a chance of liver damage possibility to one in every 1 million daily doses. That’s a pretty low chance of liver damage, especially from an herb that has been used without incident for hundreds of years. Nonetheless, it warranted that the herbal community pause and look at the data we had. The German Commission E put a stop to anyone marketing kava products in Europe, and here in the U.S., kava disappeared from the shelves.

But why was kava, which has been used for many years without incident, suddenly causing toxicity problems? One of the best theories is that instead of using only the root, as has been done throughout the history of using this plant, the leaves and stems were added. The substance pipermethystine is present in the aboveground parts of the plant and not in the root. It also happens to be hepatotoxic. Another possibility is that in the process of creating tinctures of kava, some manufacturers may have inadvertently introduced toxic substances as part of their tincturing process.

Recently, a German court lifted the effectual ban on kava. The risk-to-benefit ratio favors the benefits of this plant—the medicine used to replace its effects has more risk. Controversy will most likely continue to swirl around kava.

Regardless of the herbs you choose for yourself or your family, it’s important to keep in mind the stipulations:

• Buy only from reputable sources. Choose established herbal wholesalers whose business practices demonstrate their intention to source responsibly.
• Make your own tinctures.
• Use the herb in the way it was intended. When used occasionally for short periods of anxiety and stress, kava shines. It has not traditionally been taken every day in a therapeutic dose.
• Memberships to organizations such as the American Botanical Council can provide you with access to peer-reviewed studies on herbs used for medicinal purposes.

Buying Herbs & Herbal Products Safely

When it comes to herbal health-care products, it can be tough to learn much from labels. We recommend first researching responsible companies. Then, look for these indications of quality on product labels. All herbs listed should be designated by both their common name and their botanical name like this: Nettle (Urtica dioica). If the package doesn’t identify the botanical name, this is cause for suspicion. A given herb may go by upwards of 100 common names, but there is only one botanical name—be certain you are getting the herb you intend.

The packaging should contain all necessary labeling: Herbal products should have the ingredients, instructions on use, the appropriate FDA warning verbiage and contraindications. While some manufacturers may not agree with the principles behind the need for “warnings,” the intent of a person who doesn’t take their product seriously enough to follow the law must factor into your decision to buy. (Consider the difference between buying something homegrown and something from a store shelf. Labeling on this level is perhaps not as important when someone is not running a business.)

Beware larger-than-life claims. Claims that the herb is a “cure” should set off warning alarms. Herbs should be considered partners in our bid for balanced health. They do important work in a body that is making changes in diet and lifestyle. No reputable product will claim to do all the work for you in a pill, tincture, tea or cream.

Dawn Combs is the owner of Mockingbird Meadows Herbal Health Farm in central Ohio and the director of its Eclectic Herbal Institute. Mockingbird Meadows is nationally known for its line of herbal honey spreads. Combs is the author of Conceiving Healthy Babies: An Herbal Guide to Support Preconception, Pregnancy and Lactation.