Throughout history, people have turned to herbs and foods to treat and cure illness. Healers determined which food or plant would treat a specific disease by looking to the plants themselves for clues to how they should be used.
The DOS Philosophy
The Doctrine of Signatures (DOS) is the belief that every food and plant shares characteristics with whatever organ or body part it's helpful in treating. The characteristic might be a unique shape, color, taste or even its growing location.
Used for Centuries
In ancient times, people of religion strongly believed that, during creation, God provided humans with the ability to cure any illness by creating plants with medicinal properties. They also believed their creator gave each plant specific traits that could be used to help them determine how to medicinally use that plant.
Although similar philosophies are recorded as far back as the time of the Greek botanist, Dioscorides (40 - 90 A.D.), the term "Doctrine of Signatures" was created by the well-known Renaissance alchemist, Paracelsus (1493 - 1541). He firmly believed that the physical attributes of plants help identify the illness it treats and wrote extensively about his conviction.
In 1622, DOS gained even more popularity from Christian mystic, Jacob Boehme. Boehme claimed to have had visions that revealed nature's secrets and the interconnectivity of all things and believed God wished for him to share that knowledge. As a result, he wrote many controversial books including his famed, "The Signature of All Things" which further promoted the DOS philosophy.
Examples of Signatures
There are several types of plant and food signatures: color, shape, taste, texture and growing location. Here are some examples:
- Carrots: When sliced, carrots resemble a human eye. According to a National Institutes of Health (PubMed) abstract, carrots are a good source of carotenoids which support eye health.
- Tomatoes: A tomato has four distinct areas resembling the four chambers of the human heart. Tomatoes contain lycopene, a substance that research shows may help reduce the risk of heart disease, although more study is needed.
- Walnuts: The meat of a walnut closely resembles the human brain. Walnuts are a good source of vitamin E. A study cited by WorldHealth.net concludes that vitamin E may help protect against Alzheimer's and other cognitive brain disorders.
- Beets: Beets deep red color resembles human blood. A PubMed abstract concludes beet juice may lower blood pressure and decrease the risk of heart disease.
- Figs: Figs resemble male testes. According to Dr. Spence Pentland, figs are a good source of folate, a nutrient necessary for sperm production.
- Sweet Potatoes: Sweet potatoes are shaped like the human pancreas, an organ that helps maintain proper blood sugar levels. The American Diabetes Association lists sweet potatoes as a diabetes super food as part of a diet to maintain adequate blood sugar levels in the body.
- Skullcap: Skullcap's flowers resemble small skulls and are believed to treat brain and nervous system disorders such as seizures and anxiety.
- Goldenrod: According to "An Introduction to the Doctrine of Signatures" by Tamarra S. James, plants that have yellow flowers are believed to treat jaundice. Although the herb is not well studied in modern medicine, Native Americans used it as a jaundice remedy.
- Horsetail: While this herb looks very similar to a horse's tail, it also resembles human limbs and nerve fibers. Horsetail is known for its bone and tissue strengthening benefits, likely due to its high silica content.
- Burdock: This herb's reddish-purple flowers and stems resemble the color of blood. According to Reader's Digest's The Complete Illustrated Book of Herbs, burdock is used in Western herbal medicine to detoxify and purify the blood.
- Yarrow: A popular battlefield herb due to its ability to stop bleeding and heal wounds, yarrow's spreading wiry stems and leaves resemble the human vascular system.
Slow growing herbs with a longer than normal life span such as ginseng are believed to promote longevity and reduce age related dementia. Asian ginseng was used in ancient Chinese medicine for long life, strength and wisdom. A clinical trial showed a specific ginseng supplement improved some symptoms of aging, endocrine and immune function and helped reduce free radicals in the body.
While the above cases just barely begin to touch on the many examples of the Doctrine of Signatures, they demonstrate that folk healers may have been on to something. Research on certain herbs and foods shows that, whether by coincidence or design, the doctrine may actually ring true. Speak to a medical professional before using any herb or supplement to treat an ailment.
The debate will continue to rage on as naysayers of the doctrine will likely never be swayed while proponents will continue to support and practice it. No matter what, it can't be denied that nature is amazing and still has a lot to teach us.