Properly selected herbs provide effective therapies
Herbs have been used for their health benefits in humans and animals for thousands of years. In the past, eclectic physicians and veterinarians in the U.S. made extensive use of herbs. However, with the increased availability of effective drugs, the use of herbs significantly declined.
Now, there is a resurgence of interest in the use of herbs for therapy. In a 2016 report from the American Botanical Council, U.S. consumer spending for herbs was estimated to be $6.92 billion in 2015. This represents a 7.5 percent increase over the previous year. Importantly, this is part of a continuous trend of increased sales over the last 12 years.
With the millennia of use, extensive folklore surrounds the therapeutic use of herbs. While this folklore use has provided guidance for herb selection, current clinical application relies on a growing body of scientific research. For an herb to be beneficial, it must be safe for use, the active compounds must be effective for the intended purpose, be sufficiently absorbed after ingestion, be distributed to the target tissue, reach therapeutic levels in that tissue and remain in that tissue for an appropriate amount of time.
An additional layer of complexity involves the fact that plants contain a wide variety of compounds. For example, Boswellia, popular for its anti-inflammatory effects, contains more than 340 different compounds. Defining the therapeutically active compound(s) in plants can be challenging. Further, it is becoming increasingly clear that combinations of plant compounds work in a synergistic way which makes them more effective therapeutically at lower doses.
Many plant compounds are formed as part of the normal processes of life for the plant. Other compounds are formed by the plant for protection. For example, grapes produce resveratrol to protect the grape from fungal infections. This means that some plants will have higher concentrations of these active compounds depending on the level of need for protection.
Certain growing conditions can create stresses for plants resulting in higher or lower levels of key compounds. Therefore, it is important to recognize that there are variations in amounts of plant compounds based on the plant strain, part of the plant (i.e. leaf, flower, or root), seasonal growing conditions and storage after harvest. For example, a study on turmeric (Curcuma longa) showed a 10-fold difference in curcumin content between turmeric strains and variation in the same strain by year of production.
Hawthorn (Crataegus laevigata) is an example of an herb that has clinical effects documented with current research that is consistent with traditional use. Hawthorn leaves and flowers have long been used for heart problems. It is now known that the active compounds in hawthorn increase the force of the heart contraction, improves blood flow to the heart muscle and reduces the heart muscle oxygen demand. Clearly, for these effects to be documented in human and animal studies the active compounds must reach the heart after ingestion, and elimination must be slow enough to maintain therapeutic levels between doses.
Not all herbs are effectively absorbed. Herbs such as turmeric are felt to be poorly absorbed and do not maintain significant levels in the body for long periods of time. These factors have a direct effect on the dose of the herb, how frequently the herb is ingested, and even the combination or form used. For other herbs the method of elimination is important. For example, cranberry (Vaccinium macrocarpon) has been shown to be beneficial in certain urinary conditions. Efficacy of these compounds relies on their presence in urine. More than 40 different cranberry related compounds have been found in urine following ingestion and metabolism.
A wide variety of herbs are available with varying amounts of supportive research documenting their efficacy in patients. Properly selected herbal therapies can be effective alone or when integrated with other supportive methods. While successful use of herbs depends on appropriate selection, it also involves the use of high quality herbs and herb products that are true to label claims.
If you have questions about the use of herbs for your pet companions, contact a knowledgeable veterinary herbalist.
Ron Carsten was one of the first veterinarians in Colorado to use the integrative approach, has lectured widely to veterinarians and has been a pioneer in the therapeutic use of food concentrates to manage clinical problems. In addition to his doctor of veterinary medicine, he holds a Ph.D. in cell and molecular biology and is a certified veterinary acupuncturist and certified canine rehabilitation therapist. He practices integrative veterinary medicine in Glenwood Springs.