With an appearance similar to gray or greenish hair, usnea is the term used to refer to a genus of lichens in the Parmeliaceae family. In general, lichens are organisms that result from the symbiosis between a fungus and an alga or a cyanobacteria. They grow and hang from tree branches.
Despite being sensitive to air pollution, its use is very varied and dates back to ancient times. It is believed that they were used by the Greek physician Hippocrates to alleviate urological disorders, while they have been considered a support for the health of the kidneys, the respiratory system and the immune system by traditional Chinese medicine for more than 2000 years.
Likewise, there is scientific evidence that the species Usnea barbata is essential in South African folk medicine; there is a treatment for wounds and for inflammation of the mouth and throat. Find out everything you need to know about these lichens.
Characteristics of the Usnea Lichen
In general, the number of species that make up the genus Usnea is between 40 and 80. However, it can vary depending on the classification system of each country.
They are edible, but are not usually consumed directly. They are taken as a liquid extract, herbal tea, or supplement and applied to the skin or inside the mouth.
Usnea lichen is also a source of active components that give it beneficial health properties. Some of them are the following:
- Usnic acid: a natural antibiotic, according to a study published in Molecules.
- Norstictic acid: a compound that, according to scientific evidence, has high antioxidant activity.
- Barbatinic acid.
- Dihydropteroic acid.
- Evernic acid.
Health Benefits and Uses of Usnea
Today, the genus Usnea has been linked to health benefits such as weight loss and pain relief. However, the evidence is scant. Let’s see a little more below.
1. Promotes wound healing
Usnic acid might promote wound healing. According to studies published in Colloids and Surfaces B: Biointerfaces and Advances in Experimental Medicine and Biology, this compound can fight bacteria that cause skin infections.
While a study published in Planta Medica showed that usnic acid protects against the bacteria Staphylococcus aureus, one of the main causes of infections in skin wounds. For its part, a study in rodents found that usnic acid is capable of increasing scarring markers, such as collagen formation.
However, it is not certain that the amounts of usnic acid present in some creams are sufficient to generate the same effects. For this reason, more human studies are still required.
2. May decrease the risk of developing malignant cells
Given that usnea lichen is a source of polyphenols, antioxidants capable of fighting cell damage caused by free radicals, there is scientific evidence that it could protect against the development of malignant tumor cells.
For its part, an investigation published in Planta Medica showed that usnic acid is capable of inhibiting growth and killing cancer cells, while not harming those that are not. However, more studies are still needed in this regard.
3. Facilitates weight loss
In the ingredient list of weight loss supplements, it is common to find usnic acid. According to a study published in the International Journal of Molecular Sciences, it could stimulate weight loss by speeding up metabolism.
However, oral weight loss supplements that contain usnic acid may lead to liver failure. Although the majority of people with this side effect recovered, one group suffered from severe forms of the disorder, requiring liver transplantation.
However, although it is not yet clear if it was the usnic acid that caused these effects, the consumption of supplements to lose weight that include it as an ingredient is not recommended.
4. Other possible benefits
Usnea lichen is believed to have other potential benefits, but there are no studies to support them. Some of them are the following:
- Relieve symptoms derived from the human papillomavirus (HPV).
- Work as a pain reliever.
- Reduces fever.
- Treat respiratory and urinary tract infections.
Risks and considerations
As we have discussed, usnic acid has been linked to cases of liver failure when taken orally. For its part, diphratic acid can also be toxic if ingested in large quantities. Likewise, it is believed that drinking large amounts of undiluted tinctures of usnea lichen can cause stomach problems.
In supplements, the doses of usnic and diphratic acid vary markedly. Therefore, it is unknown which presentations could cause side effects and more research is needed.
In addition, its consumption and application is not recommended without consulting a doctor. Especially in children, pregnant and lactating.
Usnea lichen: beneficial or risky?
While it is true that there is promising scientific evidence on usnea, it is not recommended for many of the traditional uses it has. This is due to the serious side effects it causes, ranging from stomach problems to serious liver damage.
Always consult with a specialist before starting to consume any type of supplement. Remember that when it comes to weight loss, there are no magic bullets.