Guarana is native to the lower Amazon, Brazil more exactly, where it grows in abundance. Cultivated in a few localities on the South American continent, this plant has only been known in Europe since 1817. Guarana is a Brazilian name which derives from the name of the Guarani tribe , indigenous to the Amazon.
A little bit of mythology
The Guaranis attribute divine origins to this plant ; the first of them would not have been born from a seed but from the eyes of a divine child killed by a snake. Perhaps there is something to do with the fact that this tree has been deified.
The divinity would thus have liked to perpetuate the destroyed vital force for the benefit of men. Long before European botanists studied this plant; guarana was a drink that the Manes tribe prepared in secret. It was from this beverage that they drew their strength and longevity; continuing to attribute divine origins and powers to him .
A little history
The Amerindians were the first to discover the medicinal effects of guarana, with a use already observed in pre-Columbian times.
Lightly roasted as well as fermented seeds are used. The paste has been prepared in the Amazon since very ancient times, by crushing the almond with water. It is presented in the form of sticks or turtle; resistance symbol . These forms are then dried in the sun or in the oven and then eaten. In this region of Brazil, the dough is used to prepare refreshing and tonic drinks.
Traditionally, in a calabash, a stick of guarana is grated using the dried tongue of a giant fish, the pirarucu , which inhabits the Amazon basin. We do this every morning, so as to obtain the equivalent of a teaspoonful of guarana powder, to which we add a sufficient quantity of water. After ensuring that all the powder has been properly dissolved, this drink is taken on an empty stomach.
At the beginning of the 18th century, the German doctor Christian-François Paullini discovered the plant and will be at the origin of its scientific name. Europe developed its use at the end of the 19th century. Guarana is then registered with the Pharmacopoeia and recognized for its stimulating properties.
What are the main pharmacological properties of Guarana seeds?
Physical and psychological stimulant:
The traditional use of the plant on physical capacities and fatigue is related to the properties of guaranine , aka caffeine . In fact, this alkaloid of the methylxanthine family exerts a positive inotropic, negative chronotropic effect, and stimulates the breathing of bulbar centers. It increases blood pressure and muscle blood flow (but does not affect cerebrovascular flow), and improves muscle oxygen supply . It mobilizes intracellular calcium, and lowers the coagulation time, platelet aggregation, as well as the synthesis of thromboxane.
Caffeine, through its antagonistic action to adenosine, effectively reduces the feeling of fatigue .
Furthermore, guarana stimulates in vivo the cognitive abilities , including mnemonic. It thus promotes the release of acetylcholine in the hippocampus and cortex. These positive psychostimulant effects (memorization, perception, learning, attention, vigilance, intellectual capacities, coordination) have also been demonstrated in humans. Thus, in 2007, a study carried out in double blind against placebo on 26 patients with different dosages of guarana for 6 days demonstrated the improvement of cognitive capacities and mood, measured thanks to two scales: the automated evaluations of the CDR ( Cognitive Drug Research) and the Bond and Lader mood scales.
The authors of this study find, thanks to the plant, a dose-dependent improvement in memory, alertness, and the feeling of satisfaction . In addition to the known psychostimulant effect of caffeine, they suggest that other components in guarana could also explain the positive effects described. Thus, theobromine (also present in dark chocolate) acts on the mood by giving a feeling of well-being .
In vivo and in vitro , after exposure to methyl mercury, guarana exerts in particular protective effects on survival, locomotor activity , sleep and behavior , while reducing inflammatory changes.
On the other hand, guarana protects the human dopaminergic neuroblastoma cell line SH-SY5Y in vitro against rotenone-induced cytotoxicity. This neuroprotective effect on dopaminergic neurons opens the way for its possible use in Parkinson’s disease .
In addition, a 2018 study demonstrated that chronic administration of ethanolic extract of P. cupana reduces the formation of aggregates of insoluble β amyloid protein (Aß) in a model Caenorhabditis elegans of Alzheimer’s disease by through the activation of the heat shock protein (HSP) response, thereby preventing behavioral deficits and oxidative damage associated with Aβ toxicity.
A similar study of the same year, carried out with a hydroalcoholic extract of the plant in C. elegans models of Alzheimer’s disease and Huntington’s disease, actually showed activation of antioxidant activity and modulation of proteostasis. , increasing proteasome lifespan and activity, reducing intracellular reactive oxygen (FRO) forms and autophagosome accumulation, and increasing expression of superoxide oxidase 3 (SOD-3 ) and heat shock protein16.2 (HSP-16.2). These findings indicate that guarana has therapeutic potential in the fight against amyloidogenic diseases and other neurodegenerative diseases associated with aging caused by improper folding as well as brain protein accumulation.
Effect on asthenia associated with chemotherapy or radiotherapy:
In a double-blind, placebo-controlled crossover clinical study conducted in 2011 for 21 days in patients who had undergone a first cycle of chemotherapy for breast cancer , taking guarana improves perceived fatigue and quality of life , with good tolerance. The same is true for people treated with radiotherapy.
Regulation of satiety:
A double-blind, placebo-controlled clinical study shows that guarana halves the progression of food bolus in the stomach, thus increasing the length of the period of satiety.
Guarana is traditionally used as an adjunct to weight loss diets . An epidemiological study conducted in 2011 in the Amazon among people over 60 years of age showed a better metabolic status in regular consumers of guarana; lower waistline, less obesity as well as high blood pressure, lower LDL cholesterol (in women).
Clinical studies in obese subjects have shown that caffeine or guarana associated with other plants have significant effects on weight loss and its stabilization after diet , on the reduction of fat mass, on energy expenditure in of healthy subjects, on the improvement of the basal metabolism (+ 10%), on the increase (demonstrated after ingestion of a single dose of guarana) of the thermogenic activity (measurable by the increase in the respiratory quotient, reflection of lipid oxidation These metabolic effects are nevertheless attributed to caffeine, its action on the energy balance and on the increase in daily energy expenditure having been demonstrated.
In vitro , guarana exerts anti-adipogenic potential due to its ability to modulate microRNAs and genes associated with this process.
Antioxidant and cytoprotective activities:
The hydroalcoholic extract of guarana de facto limits the mortality of fibroblasts and the pro-oxidant effects (lipid peroxidation, DNA damage, oxidative stress) induced by a chemical agent releasing nitrogen monoxide (nitric oxide = NO).
The antioxidant potential of guarana is linked to its high concentration of polyphenols, which would explain its testicular protective effect vis-à-vis the toxicity of cadmium and its action of stimulating spermatogenesis.
Intestinal gastro-protective and antibacterial properties:
While decreasing the volume of gastric secretion as well as total acidity, guarana reduces gastric ulcerations induced by ethanol. This gastro-protective effect was also found with respect to indomethacin for guarana but not for caffeine alone, which suggests that this molecule would not be the only one responsible for this action.
An antibacterial activity of guarana has been demonstrated for Pseudomonas aeruginosa, Proteus mirabilis and vulgaris, Escherichia coli, Staphylococcus aureus and Bacillus subtilis.
Are there any precautions for use with Guarana?
- Due to its high caffeine content, guarana is not recommended in the event of cardiovascular disorders (hypertension, tachycardia, arrhythmia), insomnia, anxiety disorders, progressive gastric or duodenal ulcers, hyperthyroidism.
- Not recommended for people with a declared allergy to sapindaceae.
- According to the EMA, the use of guarana is not recommended in pregnant (abortifacient) or breastfeeding women, as well as in children and adolescents under the age of 18, given the presence of alkaloids in the plant. .
Side effects :
- Taking into account the possible dependence linked to the prolonged consumption of guarana and caffeine (possible cumulative effect with other sources of this molecule), withdrawal can generate headaches, irritability, restlessness, anxiety, or conversely drowsiness and confusion.
- Tachycardia, irritability, headache, restlessness, gastrointestinal disturbances due to the presence of caffeine
Precautions for use:
- To be taken with caution: In heavy consumers of food, drinks and other products rich in caffeine (coffee, tea, yerba, mate, kola nuts, etc.), given the cumulative effect of the molecule; in subjects treated with amiodarone, MAOIs and sympathomimetics other than ephedrine (theoretical interaction); in people with glaucoma
- Avoid taking before bedtime as guarana can cause sleep disturbances and reduce the effects of sedatives.
Drugs interactions :
- Combination strongly discouraged with ephedrine-based preparations.
- The caffeine contained in guarana can interact with a large number of synthetic drugs (benzodiazepines, theophylline and bronchodilators, diabetes treatments, diuretics, lithium, cimetidine, antacids, clozapine, monoamine oxidase inhibitors – MAO, alendronate, anticoagulants, antiplatelet agents, nicotine). In the event of regular and / or intensive use of guarana in combination with these molecules, seek medical advice and / or supervision.
- Pharmacokinetic interactions:
- CYP1A2 substrate
- Pharmacodynamic interactions:
- Addition of effect with antihypertensives, analgesics, triptans, theophylline (caffeine)
- Decreased effect of sedatives, anxiolytics and antidepressants (caffeine)
How to take Guarana and in what dosage?
- As a food supplement, in the form of standardized fresh plant extract, dry extract, powder, in capsules .
- Standardized fluid extract of fresh plant : 5 to 10 ml per day in a glass of water.
- Honey glycerin fluid extract : 5 ml once or twice a day in water.
- Infusion : 0.5 g to 1 g of powdered guarana or a few seeds, for 200 ml of water for 5 to 10 minutes, to be consumed once or twice a day.
There are also many guarana-based energy drinks that are rich in caffeine, often containing other substances.
In physical as well as psychic asthenia or arterial hypotension.
For exhaustion syndrome or arterial hypotension.
In the management of overweight and obesity, metabolic action and basal metabolism.
In the accompaniment of weight loss, for the satietogenic effect.
Against intellectual overwork, mental exhaustion with mood disorders.
In the fight against cognitive disorders as well as mental fatigue in a context of low thyroid or proven hypothyroidism.
Medical bibliographic sources and clinical trials :
- Fisone G. et al., Caffeine as a psychomotor stimulant; mechanism of action, Cell Mol Life Sci., 2004
- Walsh D.A. et al., Multiple pathway signal transduction by the cAMP-dependent protein kinase, Faseb J., 1994
- Huang Z.L. et al., The role of adenosine in the regulation of sleep, Curr Top Med Chem., 2011
- Cauli O. et al., Caffeine and the dopaminergic system, Behav Pharmacol., 2005
- Haskell C.F. et al., A double-blind, placebo-controlled, multidose evaluation of the acute behavioural effects of guarana in humans; J Psychopharmacol., 2007
- De Oliveira Campos M.P. et al., Guarana (Paullinia cupana) improves fatigue in breast cancer patients undergoing systemic chemotherapy; J Altern Complement Med., 2011
- Belza A. et al., The effect of caffeine, green tea and tyrosine on thermogenesis and energy intake; Eur J Clin Nutr., 2009
- De Oliveira D.M. et al., Paullinia cupana Mart. var. Sorbilis protects human dopaminergic neuroblastoma SH-SY5Y cell line against rotenone-induced cytotoxicity, Hum Exp Toxicol., 2011
- De Waele S., Van Belle S., Cancer-related fatigue, Acta Clin Belg., 2010
- Costa Krewer Car. et al., Habitual Intake of Guarana and Metabolic Morbidities; An Epidemiological Study of an Elderly Amazonian Population, Phytother Res., 2011
- Leite R.P. et al., Protective effect of Guarana (Paullinia cupana var. sorbilis) pre-treatment on cadmium-induced damages in adult Wistar testis; Biol Trace Elem Res., 2011
- Mara T. et al., Chemical and Microbiological Study of Extract from Seeds of Guarana (Paullinia cupana var. sorbilis), Lat. Am. J. Pharm., 2007
- Boasquivis P.F. et car. Guarana (Paullinia cupana); Extract Protects Caenorhabditis elegans Models for Alzheimer Disease and Huntington Disease through Activation of Antioxidant and Protein Degradation Pathways; Oxid Med Cell Longev., 2018