Pros and Cons of Guarana

This potent stimulant has health benefits, but you need to be careful

Some energy drinks use guarana as one of the stimulants that give them their kick—and a bit of nutritional value.guentermanaus/Shutterstock

If you enjoyed an energy drink recently, chances are it contained an ingredient known as guarana (Paullinia cupana). This plant, which is native to the Amazon rainforest, is the source of a substance associated with several health benefits, along with some cautionary notes.

Guarana is a Brazilian plant highly regarded by natives for its healing qualities. The mature fruit of this climbing vine is bright red and the size of a coffee berry. The black seed in the berries is a significant source of the stimulants of caffeine, theobromine, and theophylline, as well as the antioxidants of catechin, saponin, and tannin.

Health Benefits of Guarana

Kills Bacteria: It’s been suggested that caffeine, along with the tannins or catechins found in guarana, is the source of guarana’s antibacterial properties. However, it’s been shown that guarana can kill Escherichia coli and Streptococcus mutans, bacteria that can cause diarrhea and tooth decay, respectively.

Is High in Antioxidants: The various antioxidants found in guarana can help to fight cell and tissue damage related to free radical activity.

Boosts Mental Energy and Focus. The high caffeine content of guarana (the seeds contain up to six times more caffeine than coffee beans) can help to increase mental energy, reduce fatigue, and improve focus. A study comparing people who took vitamins containing guarana and a placebo group found that those who consumed the guarana had less fatigue.

Improves Memory and Learning Ability: Research has indicated that low doses of guarana (37.5 mg or 75 mg) improved learning ability and did so better than at higher doses. The authors suggested this shows that compounds other than caffeine are providing this benefit. In a study that compared the brain-enhancing compound ginseng with guarana, the use of the latter resulted in faster task performance times and better concentration.

May Aid Weight Loss. The high caffeine content in guarana may accelerate metabolism by as much as 11 percent during a 12-hour period and thus aid in weight loss. Guarana’s impact on fat cell production, however, isn’t clear.

Enhances Heart Health. You’ve probably heard of bad cholesterol (also known as low-density lipoprotein, or LDL). Guarana may reduce oxidation of this harmful substance, according to research. The antioxidants in guarana also may improve blood circulation.

Improves Skin Health: Some cosmetics contain guarana, as the antioxidants may reduce skin damage associated with aging, minimize wrinkles around the eyes, and reduce sagging skin in the cheeks.

Helps Digestive Problems: Do you experience constipation or diarrhea? The tannins in guarana may help with diarrhea since they are an astringent. Low doses of guarana can have an antidiarrheal effect. High doses (and thus more caffeine) may help with constipation.

Cons of Guarana

When consumed in amounts typically found in foods, or in the short-term for medicinal purposes, guarana is usually safe for most adults. In a 2019 review, the authors found that “guarana is not currently known to be associated causally with any serious health risks when consumed properly” and that “if guidelines for caffeine intake are respected,” using guarana is “not likely” to cause harm.

However, high doses (more than 400 mg of caffeine daily), long-term use, or use by individuals who have certain health challenges may cause mild to severe side effects. These can include stomach irritation, nervousness, vomiting, and insomnia.

Individuals who have specific conditions such as bladder control problems, diabetes, bleeding disorders, heart disease, high blood pressure, glaucoma, irritable bowel syndrome, or seizures may experience reactions associated with their health issues.

Bottom Line

Guarana is a natural remedy that may provide significant health benefits when used wisely. You can find guarana in energy drinks and as a supplement (pills, capsules, and powder), but in all cases, be aware of the caffeine content.

Sources

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WebMD. Guarana: uses, side effects, and more.