Guarana: Benefits, Dosage & Side Effects


What is Guarana?

Guarana is a shrub that is native to Brazil. It contains seeds that are often used to make supplements like drinks, tablets and powders. The guarana fruit is also highly caffeinated, and guarana seed extract is sometimes added to energy drinks to give them a natural boost. Brazilian natives have used guarana for centuries, but it has now become available all over the world. In fact, the fruit’s name is actually a nod to the Amazonian tribe that first consumed it — the Guarani.

There are many benefits to taking supplements derived from the guarana plant, particularly for maintaining energy and focus. For example, athletes often use guarana for its stimulating effects. In addition to the high guarana caffeine levels, this fruit also contains a range of other chemicals that have similar energy-boosting effects (such as theobromine). Guarana is also a popular substance for treating low libido and a lack of focus while others use it to enhance their weight loss progress. As we learn more about guarana’s effects, its numerous benefits are only becoming more evident.

Guarana Benefits

There are many different benefits to taking guarana. Not only can it be used to treat a variety of different problems, but it can also prevent health issues while simply maintaining good health in general.

The guarana plant improves focus and energy levels, enabling users to be much more productive throughout the day. The high caffeine levels alone make a big difference in boosting energy levels — guarana actually contains as much as four times more caffeine than coffee (x). Guarana supplements also increase focus and reduce mental fatigue, particularly in patients with chronic conditions (x).

Weight Loss

Guarana can help promote weight loss when combined with other weight loss strategies like a healthy diet and exercise. There are two main reasons why guarana could be effective for weight loss. The first is that the high levels of caffeine in guarana can naturally boost your metabolism and help you burn more calories (x). The second reason is that guarana may actually suppress the genes that promote fat cell growth, although more research needs to be done on this for a conclusive result (x).

Guarana also has antibacterial properties, which makes it capable of preventing bacterial infections. In particular, guarana can help kill E. coli, a bacteria that can cause illness in some cases (x). Guarana also suppresses bacteria that can cause tooth decay and other dental issues (x).

Combats Cancer

One of the most promising potential guarana benefits is that it could prevent or fight against cancer. Guarana is very rich in antioxidants, which naturally combats cell damage that leads to cancer as well as a variety of other chronic conditions (x). Studies on mice have also shown that guarana is capable of killing cancer cells and suppressing their growth (x). Although no research has been done on humans yet, this is very promising for guarana as a cancer prevention supplement.


Amazonian tribes have used guarana for centuries to treat constipation and diarrhea naturally. Guarana has high levels of tannins, which are a type of antioxidants, and these can balance the water content of your digestive tract (x). This prevents constipation and keeps your digestive process regular. However, the caffeine in guarana can also speed up the process of peristalsis, so it also works as a natural laxative (x).

Cardiovascular Health

Emerging studies indicate that the guarana berry may improve cardiovascular system health. Guarana seems to improve blood flow, which prevents blood clots and other dangerous cardiovascular problems (x). Additionally, guarana can also decrease oxidization of cholesterol and plaque buildup in your arteries, which can later contribute to other cardiovascular problems like heart disease and heart attacks (x). Though studies on humans are scarce, early research looks quite promising.

Pain Relief

The caffeine content in the guarana plant means it can be used as a mild pain reliever. Caffeine has long been used to reduce pain — the Amazonian tribes who used guarana centuries ago used it mainly to manage pain. Caffeine blocks two of the body’s most important pain receptors, which is why we don’t feel pain when we consume it in large quantities (x).

Anti-Aging Properties

When used topically in creams or lotions, guarana can have anti-aging properties for the skin. Caffeine increases blood flow to your skin, which gives it a healthier, more vibrant look. Studies have also indicated that guarana can improve skin tightness and minimize the appearance of wrinkles (x). There are cosmetics on the market that contain guarana, but you can also apply guarana extract topically in small doses.

Eye Health

When consumed regularly over a long period of time, guarana may protect against a range of degenerative eye disorders such as glaucoma, macular degeneration and cataracts (x). It also could keep your general vision quality higher, even into old age (x). However, more research is necessary to render these claims valid.

Mental Health

It has been rumored that guarana is effective for treating anxiety. Studies have shown that euphytose, a product that contains guarana, could be effective for treating anxiety (x). However, other studies focusing on guarana alone have not shown any significant impact (x). More research needs to be done to determine exactly how it affects the symptoms of anxiety and other mood disorders.

Headache Relief

Amazonian tribes have used guarana to treat common health problems, such as headaches and fever. While there currently aren’t any studies to support these specific results, guarana has been proven to have strong stimulatory effects beyond what you would get from normal caffeine (x). These could contribute to the reduction of headaches and fever that many people experience after taking guarana.

Sexual performance

Another possible benefit of taking guarana is an aphrodesiac effect, stimulating sex drives in people who have trouble getting or staying aroused (x). Because of its high caffeine content, it does naturally have this effect. However, people taking guarana for this reason must be careful not to over-consume, as this can lead to overstimulation and other issues in the long term.

How to Take Guarana

Guarana is a fruit, so the seeds and berries are both edible. Thanks to its high caffeine content, guarana is also a common ingredient in many energy drinks, teas and sodas. However, if you are taking guarana for health purposes, this isn’t the most efficient way to consume it. It’s generally best to take guarana in the form of a supplement.

Guarana Side Effects and Dosing

Although guarana has many potential health benefits, there are also some important side effects to be aware of. Most of the side effects of guarana are directly related to the fruit’s high caffeine content, and can be prevented by limiting your dose of guarana to small quantities. The side effects of guarana include:

  • Guarana can increase anxiety levels and even heighten your chances of experiencing a seizure (x).
  • The large amounts of caffeine in guarana can irritate the digestive system, making diarrhea and irritable bowel syndrome worse when taken in high doses (x).
  • High doses of guarana can lead to issues with the cardiovascular system, including heightened blood pressure and even an irregular heartbeat (x). Guarana may even exacerbate the symptoms of bleeding disorders, though this claim does require additional research.
  • High levels of caffeine, such as those found in guarana, can weaken bladder control and lead to incontinence (x).
  • Caffeine can irritate symptoms of schizophrenia, so if you have this condition, you will need to be extremely careful when taking guarana (x).
  • High levels of caffeine, such as those found in guarana, could complicate the way the body processes blood sugar (x). This makes it potentially problematic for people with diabetes. Essentially, high doses of guarana could hinder diabetics from effectively treating their low blood sugar levels.

Guarana can be very beneficial when taken consistently in small doses. To stay safe and ensure you don’t experience side effects, keep your dose limited to 250-300 milligrams per day, depending on your height and weight. You should also lower your dose if you are pregnant or breastfeeding to under 200 milligrams per day.

The Bottom Line

Guarana is an excellent supplement for people who are looking to improve their focus, physical stamina and energy levels. Athletes in particular can really benefit from the effects of guarana. It can also help keep the digestive and cardiovascular systems working regularly when taken in small doses. Worried about conditions like cancer? Guarana can be a solid preventative supplement. And on top of that, it can even aid in weight loss when taken in combination with a healthy diet and exercise. The key to experiencing these benefits from guarana is taking it in very small doses over a long period of time, as the caffeine in guarana can cause side effects when doses are too large. Guarana supplements are available in many different forms, including tablets, guarana powder and more.

**These statements have not been evaluated by the FDA. Supplements are not intended to diagnose, treat, cure, or prevent diseases — instead, they help you maintain your long-term health.