Ilex guayusa

Description

Ilex guayusa is an evergreen dioecious tree which grows 6–30 meters tall. The leaves are ovate, elliptic, oblong or lanceolate; 7–22 cm long, 2.5–7 cm wide. The flowers are small and white, arranged in thyrses. The fruit is spherical and red, 6–7 mm in diameter.

Distribution and Habitat

A tall tree native to the upper Amazonian regions of Ecuador, northeastern Peru, and southwestern Colombia, between 200–2000 meters of elevation. It is present in evergreen or deciduous premontane forests, especially ones dominated by Dictyocaryum palms. Guayusa has been collected only rarely in the wild by botanists and is known almost exclusively as a cultivated plant (especially in the Ecuadorian provinces of Napo and Pastaza).

Vernacular names

Wayusa as pronounced in the indigenous Kichwa (or Runashimi) is one of the many languages spoken by numerous indigenous nations in the Ecuadorian Amazon. Also pronounced "Why-sa" by the Kichwa people and "Why-ees" by the Shuar people.

History

A 1,500-year-old bundle of guayusa leaves was found by Harvard University ethnobotanist Richard Evans Schultes in a medicine man's tomb high in the Bolivian Andes, far beyond the natural range of the plant.

Cultivation and use

After harvest, the guayusa leaves are dried which allows flavor to develop.

Traditionally, some Ecuadorian Kichwa people boil guayusa leaves in water and consume the resulting beverage for its stimulative effects. In addition to drinking cups of guayusa like many Americans drink coffee, indigenous hunters drink guayusa to sharpen their instincts and call it the “Night Watchman" because it helps them stay alert and awake all night. Fresh leaves are used as well as dried leaves, which are dried in rolls and strung together as a wreath resembling a Hawaiian lei. In 2015, Runa Foundation carried out an extensive study on the uses and history of the plant amongst various indigenous groups throughout Colombia, Ecuador, and Peru which was published in Economic Botany in 2016, and which concludes with:

"In relation to the therapeutic uses of guayusa, we acknowledge that available museum records and accounts have not always been verified to ensure they actually refer to I. guayusa, or to a different species with similar uses. Meanwhile, I. guayusa’s stimulating and medicinal properties will continue to position it as a valued species of the Andean–Amazonian interface, especially given intensification of market–oriented guayusa production in recent years."

Chemical composition and properties

Guayusa yields xanthines such as caffeine. Other holly species with significant caffeine content are Ilex paraguariensis, or yerba mate, and Ilex vomitoria, or yaupon holly.

In addition to caffeine, guayusa also contains theobromine, commonly found in chocolate, and L-theanine, a glutamic acid analog also found in green tea.

Chemical analyses in 2009 and 2010 have shown caffeine content in guayusa of 2.90-3.28% by dry weight.

Health benefits

A growing body of evidence suggests that guayusa has a variety of health benefits:

Antioxidants

Guayusa is a potent source of antioxidants. These help protect the body against the negative consequences of oxidative stress. This protective effect is essential to healthy aging and helps reduce the risks of various forms of cancer, cardiovascular disease, and neurodegenerative disease. Antioxidant laden tea consumption in particular has been associated with reduced incidences of digestive tract cancers and better cardiovascular health.

Weight Loss

The caffeine in guayusa helps suppress appetite and thereby promote weight loss. With slightly more caffeine than black tea, but a lower amount than regular coffee, guayusa provides the benefits of caffeine without the negative effects of excess.

Digestion and Immunity

Guayusa has a long history of being used as a digestive aide and in medicinal brews. This is primarily due to the high levels of naturally occurring compounds known as methylxanthines. Chief among these are theobromine and caffeine. When consumed in large enough quantities, guayusa helps to keep the digestive tract running smoothly and prevents infections from occurring.

Myths and legends

Michael Harner, the founder of the Foundation for Shamanic Studies describes how “the Jivaro say guayusa is so habituating that before it is offered to a visitor, he is warned that once he drinks it, he will ever always after return to the Ecuadorian Jungle.”

The Kichwa people claim that guayusa induces dreams that foretell whether hunting expeditions will be successful.