Also known as: Paullinia cupana, Guaranine, Brazilian cocoa, Guarana seed extract
BotanicalGood evidence
An Amazonian seed containing more caffeine by weight than coffee beans. The caffeine releases more slowly because of the seed's tannin content, which is the one genuine advantage over caffeine anhydrous.
Typical dose
50.0–300.0 mg per day
45-60 minutes before; earlier in the day given the long tail
What it is
Guarana is the seed of Paullinia cupana, a climbing plant native to the Amazon basin, used for centuries by indigenous peoples and now a staple of Brazilian soft drinks.
The seeds contain 2 to 6 per cent caffeine by weight, several times more than coffee beans. Guaranine, sometimes listed separately on labels, is simply caffeine.
Extracts are standardised to caffeine content, commonly 10 or 22 per cent. Working out the actual caffeine dose from a guarana label requires that percentage, and products that omit it are effectively hiding the dose.
How it works
Most of guarana's effect is caffeine antagonising adenosine receptors, exactly as caffeine from any other source does.
The distinguishing feature is release rate. Guarana seeds are high in tannins, which bind the caffeine and slow its release in the digestive tract, producing a gentler rise and a longer tail than the sharp spike from caffeine anhydrous.
The seeds also contain theobromine, theophylline, saponins and catechins. Some research suggests these contribute effects beyond the caffeine, though the caffeine accounts for the bulk of what people feel.
What the evidence shows
The caffeine effects are as well established here as anywhere, since it is the same molecule with an enormous evidence base behind it.
Slower absorption compared with caffeine anhydrous has been demonstrated, which supports the smoother-onset claim.
Some trials have reported cognitive effects at guarana doses supplying very little caffeine, suggesting the other compounds contribute. That research is limited, and anyone buying guarana should assume they are mostly buying caffeine with a slower release.
Dosing
Dose by caffeine content rather than extract weight. A 22 per cent extract at 300 mg supplies around 66 mg of caffeine, roughly two-thirds of a cup of coffee.
Aim for a total caffeine intake of 200 to 400 mg from all sources, counting guarana within that rather than on top of it. Products combining guarana with caffeine anhydrous are common, and the totals add up faster than people expect.
Take 45 to 60 minutes before you need it, slightly earlier than caffeine anhydrous given the slower release. The long tail also means later dosing affects sleep more than an equivalent amount of plain caffeine.
At a glance
Common forms
Guarana seed extract (10-22% caffeine), Guarana powder, Within energy drinks and pre-workouts
Half-life / duration
Slower onset than caffeine anhydrous with a longer tail
Timing
45-60 minutes before; earlier in the day given the long tail
Competition status
Permitted — caffeine is on the WADA monitoring programme rather than the Prohibited List
Category
Botanical
Safety and side effects
Guarana carries the same considerations as caffeine: restlessness, raised heart rate, disturbed sleep and digestive upset at higher intakes.
The particular risk is underestimating the dose. Because the caffeine is not declared as caffeine, people routinely take guarana alongside coffee or energy drinks without counting it.
Speak to your doctor before use if your heart rhythm or blood pressure is being managed, if you are prone to feeling anxious, or if you take regular medication. Not suitable during pregnancy at supplemental doses.
Who should avoid it
Count the caffeine toward your daily total from all sources. Speak to your doctor before use if your heart rhythm or blood pressure is being managed, if you are prone to feeling anxious, or if you take regular medication. Avoid at supplemental doses in pregnancy and breastfeeding. Not suitable for under-18s.
This entry is provided for information only. Food supplements should not be used as a substitute for a varied and balanced diet and a healthy lifestyle. Consult a qualified healthcare professional before use if you are pregnant, breastfeeding, taking medication or under medical supervision.
