Thyme and Thymol: Uses, Potential Health Benefits, and Safety
A Useful and Lovely Herb
Thyme is a lovely herb that has been used for culinary and medicinal purposes since ancient times. People of the past valued the plant as a tasty addition to meals, as a treatment for diseases, and as a preservative. Today the plant is popular with people who enjoy its interesting flavour and scent as well as those who like to use it as an ornamental plant or a traditional medicine. Thyme leaves are a great addition to food and make a flavourful tea.
Thyme contains an antimicrobial oil that contains a variety of chemicals. The most effective germ killer in this oil appears to be a chemical called thymol. Thymol has killed both bacteria and fungi in lab equipment. The chemical is used in toothpastes and mouthwashes in an attempt to improve oral health and is present in some products used to treat toenail fungus. It's also used to kill mites and mold in beehives and is registered as a pesticide. Thymol is added to perfumes and cosmetics to provide fragrance.
The information in this article is given for general interest. Anyone with questions or concerns about the effects of thyme or thymol should consult a medical professional.
The Plant and Its Culinary Uses
Thyme is a member of the mint family. Many varieties of the plant exist. These often have delightful names such as orange balsam thyme and passion pink thyme. The herb grows in the wild and is also cultivated as an ornamental or food plant.
The type of thyme that is most often used medicinally is the common thyme, or Thymus vulgaris. The plant is evergreen. It has small grey-green leaves and pale pink to purple flowers. It's native to southern Europe but is cultivated in many parts of the world.
Thyme adds flavour to a wide variety of foods, including meat, fish, beans, vegetables, tomatoes, cheese, and egg dishes. The dried leaves add a lovely taste to oil or vinegar. Thyme honey is a delicious treat. It's made by bees that collect nectar from thyme flowers.
Thyme is pronounced like the word "time" while thymol is pronounced "thigh-mol".
Traditional Uses of Thyme Tea
Thyme leaves or flowers are often soaked in hot water to make a tea or infusion. The tea has traditionally been used as an expectorant to relieve coughs. An "expectorant" enables mucus to be coughed up from the airways. The tea has also been used to relieve indigestion and flatulence.
When it's used in reasonable amounts, thyme is considered to be safe. For many of us, it's worth trying a tea made from the herb to see if it helps congestion or indigestion. There are exceptions to this rule, however, as described in the "Safety" and "Caution" sections below. The herb should never be used excessively by anyone. If someone has a continuous, repeated, or severe respiratory or gastrointestinal problem, they should visit a doctor.
Thyme oil and thymol are more concentrated products than the whole plant or a tea made from the plant and should be treated with care. Unlike the herb, these isolated substances shouldn't be used casually.
Not all plants with "thyme" in their common name are Thymus vulgaris and not all of them have been tested for medicinal benefits. This factor needs to be considered when choosing a plant for medicinal use.
How to Make Tea From the Thyme Plant
Antibacterial Properties of the Oil
Many experiments have shown that in the laboratory thyme oil can kill bacteria. Some examples of the oil's antibacterial activity are listed below.
- Researchers in Japan tested fourteen essential oils to see whether their vapours could kill bacteria that cause respiratory diseases. They found that thymol in thyme oil was one of the most effective germ killers.
- Researchers in Greece found that thyme oil killed drug-resistant Staphylococcus bacteria and was the most effective agent out of the eight essential oils that were tested.
- Food scientists in the Netherlands discovered that when five essential oils were tested, thyme oil and oil of oregano had the best ability to kill Escherichia coli (or E. coli). The researchers concluded that either of these oils would be an effective material to preserve foods.
These results are impressive, but they were obtained in the lab instead of from clinical tests on people or in real-life situations. Chemicals tested in lab equipment may work the same way in humans, but in the body they may be broken down, inactivated, or diluted instead. It's important to note that the concentration of thyme oil is significant in determining its effectiveness at killing a particular bacterium and also in determining its safety for humans.
A thyme extract has killed acne bacteria in the lab, which caused excitement when it was announced. As the dermatologist in the video below states, however, the effect of the extract was tested in lab equipment, not on people's skin.
Candida albicans is a type of yeast. Yeasts are single-celled fungi. The bodies of other fungi consist of branching threads called hyphae. Candida is an unusual yeast because it can exist in both a single-celled form and a hyphal form.
Candida albicans can cause annoying infections, but these generally aren't dangerous. However, in people with impaired immune systems, such as those with AIDS or those who are taking immunosuppressive drugs, Candida infections can be very serious. The ability to transform from a cellular form to a hyphal form seems to be an important part of the yeast's attack process. According to research performed at the University of Milan, thymol hinders this process.
Thymol also fights a fungus called Aspergillus. This fungus can cause a serious lung infection called aspergillosis. Researchers at the USDA (United States Department of Agriculture) have found that in lab tests thymol can make other drugs work more effectively. Thymol improves the action of drugs used to treat aspergillosis as well as drugs used to treat Candida and Cryptococcus infections. Once again, though, these results were discovered in the lab instead of in sick humans.
Thyme Oil and Alopecia Areata
One experiment showed that thyme oil mixed with other oils and massaged into the scalp was sometimes helpful for a condition called alopecia areata. This is a disorder in which hair is lost in round patches from the scalp or another part of the body. Generally, the sufferer is in good health apart from their hair loss. However, the person's immune system attacks their hair follicles and suppresses hair growth. There seems to be a genetic component to the disorder.
Researchers at the Aberdeen Royal Infirmary performed a seven month trial to see if massage with essential oils could help alopecia areata. The test oil contained thyme, rosemary, lavender, and cedarwood essential oils in a mixture of two carrier oils—jojoba oil and grapeseed oil. Some people were massaged with a mixture of carrier oils that lacked the essential oils.
44% of the 43 people who were massaged with the essential oils showed improvement compared to 15% of the 41 people massaged with only carrier oils. The decision as to whether "improvement" had occurred was made by independent observers looking at photographs. The observers didn't know which treatment the people in the photographs had received. The result of the essential oil treatment may not seem wonderful, but alopecia areata is a hard condition to treat.
The results of the experiment were reported in 1998. That certainly doesn't mean that they are invalid, but It would be good if a new experiment was performed to collect additional data.
Anyone who is losing their hair should visit their doctor for a diagnosis and treatment suggestions before trying an essential oil as a treatment.
Traditional Uses of the Thyme Plant
Thymol as an External Disinfectant
The Environmental Protection Agency (EPA) in the United States has created a list of disinfectants that appear to destroy the SARS-CoV-2 virus when applied to surfaces in the environment. The virus causes COVID-19. The product list is shown on the EPA web page mentioned in the "References" section below. At the time when this article was last updated, a product containing thymol was the seventh item on the list. Performing a search for "thymol" in the "Active Ingredient" category revealed four additional products.
It's very important that the reader notes that the list contains items for external use only. The products mentioned have a specific content mixture, formulation, and/or ingredient concentration that may be dangerous. They mustn't be used internally. All of the instructions accompanying a product must be followed carefully. The fact that the EPA has added the thymol products to the list is interesting, though. It adds further credence to the idea that thymol can destroy pathogens (entities that cause disease) in certain situations.
When using an EPA-registered disinfectant, follow the label directions for safe, effective use. Make sure to follow the contact time, which is the amount of time the surface should be visibly wet...These products are for use on surfaces, NOT humans.— Environmental Protection Agency
Some Herbal Folklore
Some interesting facts about thyme, such as the ones below, are very widely reported. These facts may or may not be true, but they contribute to a rich folklore.
- Ancient Egyptians included thyme oil in the embalming fluid used to make their mummies.
- Ancient Roman soldiers bathed in thyme water to give themselves courage and energy.
- In Ancient Greece, thyme was burned as incense in temples.
- European ladies embroidered a sprig of thyme as a token for their knights, or they placed a sprig of real thyme on a scarf for the knights.
Safety of Thyme and Thymol
Thyme has been eaten as a food for a very long time and is considered to be safe when used as a herbal addition to meals or as a tea. There is some evidence that thyme slows blood clotting, however. It would therefore be a good idea to avoid the herb for at least two weeks prior to surgery. It should also be avoided by people taking a medication that is known to interfere with the blood clotting process, such as aspirin, ibuprofen, naproxen, heparin, and warfarin.
Thyme doesn't seem to be dangerous for pregnant or nursing women, but the herb should be used in normal food amounts until more research is done. It's probably best to use the whole herb instead of concentrated extracts or infusions.
Products containing thymol as a separate ingredient should be used according to the instructions accompanying them. These instructions should be read carefully in order to ensure safety.
How to Grow Thyme Indoors
Caution When Using Herbs Medicinally
Thyme has been a significant part of many cultures. Its attractive flowers, wonderful aroma, and interesting taste have long been appreciated. Modern laboratory tests support the idea that the thymol in thyme oil kills bacteria and fungi. Clinical tests need to be performed to confirm the health benefits of thymol inside the human body, though.
As is true for many herbs that are considered to be medicinal, there is anecdotal evidence for thyme's health benefits but limited scientific evidence. This means that we should take certain precautions when we use thyme or another herb medicinally.
- First, we need to make sure that the herb is considered to be safe when used in moderate quantities.
- Secondly, we should never use the herb in excessive amounts, especially if it's taken internally.
- In addition, pregnant women, people with serious diseases, and people taking a medication should consult their doctor before using a herb in anything more than food quantities.
Since thyme is safe to eat and is very flavourful, it's a wonderful herb to add to food. I love thyme and usually have it in my kitchen. It's an interesting and useful plant.
- Essential oils and respiratory pathogens from Oxford University Press
- Essential oils to fight superbugs from the phys.org news service
- Thyme oil and E. coli from the NIH (National Institutes of Health)
- Thymol and Candida albicans from the NIH
- Thymol and Aspergillus from the USDA (United States Department of Agriculture)
- Essential oils and alopecia areata from JAMA Dermatology (Journal of the American Medical Association)
- Thyme uses and safety from WebMD
- Disinfectants for use against SARS-CoV-2 when applied to external surfaces from the EPA (Environmental Protection Agency)
This content is accurate and true to the best of the author’s knowledge and does not substitute for diagnosis, prognosis, treatment, prescription, and/or dietary advice from a licensed health professional. Drugs, supplements, and natural remedies may have dangerous side effects. If pregnant or nursing, consult with a qualified provider on an individual basis. Seek immediate help if you are experiencing a medical emergency.
© 2013 Linda Crampton