Guarana: uses, dosage & background

Siski Green / 07 September 2020

Guarana has been used in South America for thousands of years, and is now taken as a supplement to aid weight loss and a stimulant.



Guarana is considered to be coffee’s somewhat more high-powered cousin. Growing in the Amazon, the plant’s bright red berries open up to reveal a white and black ‘nut’ inside, looking a lot like an eye.

What is guarana used for?

If you’re in need of a pick me up and coffee isn’t doing it for you, guarana could be an option. It’s also used for weight loss. Guarana has a high antioxidant content, too, so could potentially be useful against cancer, inflammation and heart disease.

What’s the history of guarana?

Guarana the substance is extracted from a climbing plant, called Paullinia cupana, from its fruit. The seeds of the fruit are ground down (much like coffee beans from the coffee berries). Amazonian tribes have been using it for centuries but historians aren’t sure how long since there is very little written evidence. They prize the berries for the energy they provide, use them when fasting (to help reduce appetite) and to increase alertness, among other things.

What’s the best way to take guarana?

There are a huge range of energy drinks containing guarana – and all with different amounts of the substance. For a low daily dose, look for beverages or supplements that give you around 70mg per day. If you want to up the effects, for weight loss, for example, you can go up to 200mg a day.

Does guarana really work?

Guarana contains caffeine, theobromine (also a stimulant), and theophylline (a substance used to treat symptoms of respiratory disease). These are all natural stimulants. Research published in medical journal Appetite found that it helped prevent mental fatigue and improved cognitive performance. It’s also been found to help promote learning.

Guarana also contains a variety of substances that could provide health benefits including tannins, saponins and catechins. Antioxidant content is on a par with green tea. That makes it a potential aid in preventing cancer, along with fighting heart disease and other inflammatory disorders.

Taking 37.5 to 75mg of guarana seems to be the most effective in terms of improving cognitive function.

Caffeine, found in guarana as well as coffee, can boost your metabolism by up to 10% over a 12 hour period, according to research published in the American Journal of Clinical Nutrition. This could in turn mean you burn more calories in that time.

Guarana can also be used as a laxative and to ease symptoms of diarrhoea, depending on how much is taken. Tannins in guarana may aid in preventing loss of water during diarrhoea, preventing dehydration but only when taken at low doses. Taken at higher doses with more caffeine is likely to stimulate the digestive process, promoting bowel movements.

Where can I get guarana?

Guarana is available in supplement form in healthfood shops and online and you’ll also find it in many energy drinks too.

How long does guarana take to work?

Like a coffee, the effects of guarana should be felt within 15-20 minutes. The tannins in guarana are said to help maintain a longer period of extra energy but even so, you may feel a drop in energy levels after a few hours.

What are the side effects of taking guarana?

Some people report nervousness and even anxiety, it may also increase your blood pressure and heart rate. Some people find it irritates their stomach.

Are there any contraindications when taking guarana?

If you are taken medications for blood pressure or other heart issues, see your GP before taking guarana.

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The material is for general information only and does not constitute investment, tax, legal, medical or other form of advice. You should not rely on this information to make (or refrain from making) any decisions. Always obtain independent, professional advice for your own particular situation.