It also contains caffeine, which makes it a popular ingredient in energy drinks.
Caffeine is well-known for stimulating your central nervous system, waking you up, and helping you focus.
As a result, guarana may have some antioxidant effects.

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In general, antioxidants attack free radicals.
Free radicals can damage components and systems within the body, including the hereditary materialDNA.
The energy boost you get when you consume an energy drink containing guarana comes from its high caffeine content.
More research is needed before scientists will know if there’s any validity to these claims.
For these reasons, it might be challenging to quantify guarana’s effects.
Future high-quality clinical trials should study more standardized guarana products and dosages.
In laboratory studies and animal studies, the extract has been found to have antitumor and anticarcinogenic effects.
Some clinical trials have found that guarana may also help relieve some of the side effects of cancer-targeted treatment.
Weight Loss
Animal studies suggest that guarana seed powder may help with weight loss.
It affects the central part of the retina, the light-sensitive tissue located at the back of the eye.
Age-related macular degeneration can lead to irreversible vision loss.
One study found that guarana extract could help reduce retinal cell damage brought on by oxidative stress.
The study also found that guarana consumption seemed to be correlated with self-reported good vision.
Side Effects and Precautions
As with many medications and natural products, guarana can have side effects.
No supplement is intended to treat, cure, or prevent disease.
However, guarana toxicity likely resembles that of a caffeine overdose.
In the United States, guarana is a common ingredient in energy drinks.
This tends to be the most popular way to consume it.
Guarana is also available as a powder, which can be used to prepare tea.
Guarana supplements are available in several different forms, with capsules being the most common.
Other supplement forms include:
Vegetarian and vegan options might also be available.
You may also see guarana in combination with other ingredients.
The specific dose may vary based on the dosage form and any medical conditions you may have.
To safely take natural products like guarana, inform your healthcare providers and pharmacists about any medication changes.
This includes over-the-counter (OTC), herbal, natural medicines, and supplements.
As a result, some supplement products may not contain the ingredients listed on the label.
Summary
Guarana is naturally available as a native Amazonian plant from the soapberry family.
But like any medication or natural product, side effects and interactions are possible.
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