Guarana extract from the plant Paullinia cupana has high caffeine content with strong antioxidant properties. Few studies have suggested the potential of using guarana extracts in reducing fatigue and depression symptoms, as well as hot flashes in breast cancer patients who are undergoing chemotherapy or have completed the treatment. However, the evidence is not sufficient enough to recommend using guarana extracts along with specific cancer treatments in cancer patients and survivors. Also, a study done on head and neck cancer patients did not find any benefits of using guarana extracts for improving quality of life and related symptoms post treatment completion. If used in excess, guarana can also result in side-effects.
What is Guarana?
Guarana or Paullinia cupana is a vine native to the Amazon rainforest in South America. The guarana fruit contains caffeine-rich seeds with 3.6 to 5.8% caffeine content, which is around four times the amount of caffeine usually found in coffee beans (Dimitrios Moustakas et al, PLoS One., 2015).
Apart from caffeine, guarana also contains stimulants such as theophylline and theobromine, as well as other active ingredients including saponins, tannins, catechins, starches, polysaccharides, pigments, fats, and choline.
Guarana extracts are produced by processing the guarana seeds into a powder. Guarana extracts are available in the form of powder, tablets, and capsules. It is used in certain beverages as a flavoring ingredient and also in high-energy drinks and protein bars due to its high levels of caffeine and energy-boosting potential.
Purported Uses/Health Benefits of Guarana Extracts
Guarana extracts have strong antioxidant properties. The fruits or seeds of the guarana plants (Paullinia cupana) are considered to have medicinal properties and guarana extracts have been used for various health conditions since years, though scientific evidence are not available for many of these purported uses and benefits.
Following are some of the conditions for which people have been using guarana extracts:
- As a stimulant
- For weight loss
- To reduce mental and physical weakness/fatigue
- For diarrhea
- For heart problems
- For headache
- For joint pain
- As an astringent
- For backache
- For heat stress
- To treat low blood pressure
- For chronic fatigue syndrome
- Ingredient in energy and weight loss products
- To prevent malaria and dysentery
- To increase urine flow
Side-effects of Guarana Extracts
If taken in excess, guarana extracts may lead to different side-effects such as :
- Increased heart rate
- Increased blood pressure
- Nervousness and anxiety
- Stomach upset
Use of Guarana Extracts/Paullinia cupana by Cancer Patients
Though there are few clinical studies which studied the impact of Guarana extracts in Cancer Patients, the evidence is insufficient to draw a conclusion.
Guarana Extract (Paullinia cupana) Use may improve Appetite and Stabilize Weight in Patients with Advanced Cancer
In a study done by the researchers from ABC Foundation Medical School in Brazil, they evaluated data from 18 advanced cancer patients who were given 50 mg dry guarana extract and found that 2 patients improved their weight above 5% from their baseline and 6 patients had at least a 3-point improvement in appetite when supplemented with guarana extracts. The study suggested that taking guarana extracts may have benefits on cancer related fatigue and may improve appetite. (Cláudia G Latorre Palma et al, J Diet Suppl., 2016)
Guarana Extract (Paullinia cupana) Use post Cancer Treatment may worsen Quality of Life in Head and Neck Cancer Patients
Researchers from the Faculdade de Medicina do ABC-FMABC in Santo André, Brazil carried out another phase II prospective study, and evaluated data from 60 Head and Neck Cancer patients of stage I-IV before, during, and after chemoradiotherapy who were either given placebo or 50 mg guarana twice a day during the chemoradiotherapy treatment. The study found a significant deterioration of quality of life of the patients after the second cycle of chemotherapy in patients who took guarana compared to the those who didn’t. Even though patients who consumed guarana extracts had improvement in pain, social eating, swallowing, coughing, and weight loss after the first cycle of chemoradiotherapy, after the treatment, the condition worsened, resulting in greater use of a nasogastric tube and increased use of analgesics. (Suelen Patrícia Dos Santos Martins et al, J Diet Suppl., 2017)
The researchers suggested that guarana extract use may not be beneficial for this Head and Neck Cancer patient population.
Guarana Extract (Paullinia cupana) may Improve Fatigue in Breast Cancer Patients undergoing Systemic Chemotherapy
In a different clinical study done by the ABC School of Medicine, Santo André, Sao Paulo in Brazil, the researchers evaluated the effectiveness of guarana extract on fatigue, sleep quality, anxiety, depression symptoms, and menopause in a group of 75 breast cancer patients who completed their first cycle of chemotherapy, out of which 32 patients were given 50 mg dry guarana extract daily for 21 days. The study found that Guarana may be effective for the short-term treatment of fatigue in breast cancer patients receiving chemotherapy. (Maira Paschoin de Oliveira Campos et al, J Altern Complement Med., 2011)
However, more studies are needed to confirm these results.
Guarana Extract (Paullinia cupana) may not Improve Post-radiation Fatigue and Depression in Breast Cancer Patients
In a randomized clinical trial done by the same Institution, with 36 breast cancer patients undergoing adjuvant radiation therapy, few patients received 75 mg guaraná extracts daily p.o. and rest received placebo. The study didn’t find any significant difference in fatigue and depressive symptoms in breast cancer patients undergoing radiation therapy supplemented with guaraná or those supplemented with placebo. (Vanessa da Costa Miranda et al, J Altern Complement Med., 2009)
Guarana Extract (Paullinia cupana) may help Control Hot Flashes in Breast Cancer Patients
In another prospective phase II pilot study done by the same research group, they evaluated whether intake of guaraná extracts (Paullinia cupana) could reduce the number and severity of hot flashes in breast cancer survivors who had completed the cancer treatment 3 months before. The study found that out of 15 breast cancer patients who completed the study, 10 had more than 50% reduction in hot flashes both in terms of the numbers of hot flashes as well as severity, with no reported toxicities. (Saulo Silva Oliveira et al, Einstein (Sao Paulo)., 2013)
Different studies suggested that Guarana extract (Paullinia cupana), with high caffeine content and strong antioxidant properties, may have the potential to reduce fatigue and depression symptoms, as well as hot flashes in breast cancer patients undergoing chemotherapy or breast cancer survivors who completed the treatment. However, the evidence is not strong enough to recommend the same in breast cancer patients and survivors. Another study done on head and neck cancer patients also found no benefits of using guarana extracts for reducing fatigue and depression symptoms post treatment. Additionally, guarana extracts can cause side-effects if used in excess.
Cancer patients often have to deal with different chemotherapy side effects which affect their quality of life and look out for alternative therapies for cancer. Taking the right nutrition and supplements based on scientific considerations (avoiding guesswork and random selection) is the best natural remedy for cancer and treatment related side-effects.