Home Ingredients Kola Nut (Cola nitida)

Kola Nut (Cola nitida)

Cola nitida, Cola acuminata
Evidence Level
Preliminary
5 Clinical Trials
5 Documented Benefits
1/5 Evidence Score

Kola nut is the seed of Cola nitida and Cola acuminata, evergreen trees native to West Africa, where the bitter nut is chewed during work and social life and offered as a sign of respect. It is a caffeine source: a laboratory analysis of three kola types reported 18 to 24 g of caffeine per kg (an estimated 18 to 24 mg per gram; fresh or dry weight not stated), and theobromine is its other main stimulant, alongside large amounts of catechin-type polyphenols. Kola extract is used as a flavoring in cola-type drinks and appears in some energy and weight-management supplements. No controlled human trial has tested kola nut itself for energy, focus, exercise or body weight; the only controlled human study measured a drug interaction. Its effects are expected to follow its caffeine dose, so count it toward your daily caffeine total and see our caffeine page for that evidence.

Studied Dose No dose of kola nut has been tested in people for energy, focus, exercise or weight. The one controlled human study gave a single 12.5 g serving of kola nut to measure a drug interaction; by our estimate from one analysis (18 to 24 mg caffeine per gram), that is roughly 225 to 300 mg of caffeine.
Active Compound Caffeine (18 to 24 g per kg in one analysis of three kola types) and theobromine, plus polyphenols such as (+)-catechin, (-)-epicatechin and procyanidins B1 and B2.

Benefits

Natural source of caffeine and theobromine

Laboratory analysis of white and red Cola nitida and Cola acuminata nuts from Nigeria found 18 to 24 g of caffeine per kg, an estimated 18 to 24 mg per gram (the abstract does not say fresh or dry weight), so by our arithmetic 5 g of nut would supply roughly 90 to 120 mg. A food-safety review names caffeine and theobromine as kola's two main active constituents. Amounts vary by nut and product, so check the label.

Supported by Trial 1

Traditional chewing during work and social gatherings

Across West Africa the nut is chewed by laborers and at social gatherings, given as a sign of respect and offered in ceremonies, and it has long been credited with easing fatigue, hunger and thirst. These are traditional and historical uses, not trial results, and many of the old medicinal claims made for kola are exaggerated.

Supported by Trial 3, Trial 1

Flavoring use in cola-type drinks

Kola nut extract is used by the food industry as a flavoring, including in cola-type beverages. A safety review estimated intake of the extract at 0.69 mg per kg of body weight a day and judged that its effects likely parallel those of a roughly equivalent dose of caffeine, though it could not define a no-adverse-effect level for kola extract itself.

Supported by Trial 5, Trial 2

Effects in rat studies that track its caffeine

Animal work: in rats given kola extract, caffeine extracted from kola, or decaffeinated kola for six weeks, both kola extract and caffeine raised blood pressure and lowered body weight, and the authors concluded kola's effects on blood vessels come from its caffeine. Their extract tested at 51% caffeine. Not tested in people.

Supported by Trial 1, Trial 2

Human studies of kola cover drug interactions and patterns of use

The only controlled human study of kola nut gave 12.5 g with an antimalarial drug to 15 healthy men and measured drug blood levels. Other human data are surveys, case reports and observational studies. No trial has tested kola for alertness, exercise or weight, so evidence for those effects comes from caffeine research, not kola.

Supported by Trial 1

Mechanism of action

1

Caffeine is the main active stimulant

A food-safety review judged that the pharmacological and toxicological properties of kola nut extract parallel those of a roughly equivalent dose of caffeine, and a rat study reached the same conclusion for blood vessel effects. How caffeine works, and the human evidence for it, is covered on our caffeine page.

2

Caffeine bound to catechins in the fresh nut

In freeze-dried fresh kola seeds and a stabilized extract, up to 91% of the caffeine was bound to catechin through hydrogen bonds, while in dried seeds none was bound. The researchers proposed that this may explain differing effects of fresh and dried nuts, an idea that has not been tested in people.

3

Rich in catechin-type polyphenols

The same analysis that measured caffeine found (+)-catechin at 27 to 37 g per kg, (-)-epicatechin at 20 to 21 g per kg and procyanidins B1 and B2, and kola extracts showed antioxidant capacity in test-tube assays. These are laboratory findings with no human outcome data.

4

Possible binding of drugs during absorption

When kola nut was taken with the antimalarial halofantrine, drug levels fell while half-life did not change significantly, and the researchers proposed that kola components form a complex with the drug during absorption. This explanation was not directly tested, and no other drug has been tested with kola in a controlled human study.

Clinical trials

1
Kola Nut and Halofantrine Blood Levels: Randomized Crossover in Healthy Men
PubMed

Randomized Latin-square crossover study of a single 500 mg dose of the antimalarial drug halofantrine taken alone or with 12.5 g of kola nut, with a 6-week washout; a separate paper from the same 2003 to 2004 study reported heart rhythm (ECG) results. (Kolade et al. 2008, Eur J Clin Pharmacol)

15 healthy male volunteers in Ibadan, Nigeria for the drug-level analysis; the ECG paper describes 18 healthy men.

With kola nut, peak halofantrine levels fell from 179 to 98 ng/ml and total exposure (AUC) from 17,450 to 11,821 ng x h/ml, and its active metabolite fell by about half; time to peak and half-life did not change significantly. In the ECG paper, QTc rose slightly in all three arms without statistical significance, yet its abstract concludes that kola significantly decreased the cardiac effect of halofantrine, a claim its own results do not support. It also gives the kola dose as 12.5 mg (12.5 g in the drug-level paper) and a baseline table of 48 subjects split 17, 11 and 20, which does not match an 18-person crossover. There was no kola-only arm, so neither paper measured kola's own effects.

2
Kola Nut Intake and Indigestion: Case-Control Study in Nigeria
PubMed

Case-control study comparing intake of alcohol, kola nut and NSAID painkillers, and smoking, with endoscopy and stomach biopsies, in people with and without non-ulcer dyspepsia in northern Nigeria. (Holcombe et al. 1991, Trans R Soc Trop Med Hyg)

40 patients with strictly defined non-ulcer dyspepsia and 40 matched volunteers without symptoms.

Kola nut ingestion was the only factor that differed significantly between the two groups. Gastritis and H. pylori infection were common in both groups. A case-control design shows an association, not that kola causes indigestion.

3
Kola Chewing and Palate Keratinization: Cytology Study in Nigerian Men
PubMed

Cross-sectional exfoliative cytology study of the palate lining comparing smokers who chewed kola, smokers, kola chewers and men who did neither. (Odukoya et al. 1990, Afr Dent J)

96 Nigerian male volunteers aged 17 to 65.

Smoking and kola chewing both significantly influenced palatal keratinization, which was highest in smokers who also chewed kola, then smokers, then kola chewers, then non-users. The authors suggest kola adds to smoking-related keratinization; the clinical meaning of this marker is not established.

4
Kola Nut Use and Drug Clearance: Observational Study in Gambian Villagers
PubMed

Observational study of saliva antipyrine half-life, a marker of how fast the liver clears some drugs, analyzed by multiple regression against kola use, diet and body measures. (Fraser et al. 1976, Clin Pharmacol Ther)

49 healthy Gambian adults aged 20 to 60 (27 men, 22 women).

Antipyrine half-life averaged 13.6 hours and was longer with cola nut consumption; sex, cola nut use, hemoglobin in women and height in men together explained 36% of the variation. This was a single observational study, so the link is not settled.

5
Kola Use During Pregnancy: Cross-Sectional Survey in Ibadan
PubMed

Cross-sectional questionnaire study of kola nut use, frequency, amount and reasons among pregnant women in Ibadan, Nigeria. (Atiba et al. 2023, Sci Rep)

478 pregnant women in all trimesters (mean age 28.7).

33.9% reported kola use during pregnancy and 29.3% in the current pregnancy; among current users, 39.3% used it frequently and 32.9% in high quantities. Most users (93.7%) took it to prevent spitting, nausea and vomiting. The survey measured use, not safety or benefit.

Side effects and drug interactions

Common Potential side effects

Kola's caffeine can cause what the FDA lists for too much caffeine: increased heart rate, palpitations, high blood pressure, insomnia, anxiety, jitters, upset stomach, nausea and headache. Count kola toward the 400 mg a day the FDA cites for most adults; EFSA considers single doses up to 200 mg not a safety concern for healthy adults.
Stomach: in a Nigerian case-control study, kola nut intake was the only factor that differed between 40 people with indigestion and 40 without. This shows an association, not proof of cause.
Mouth: two case reports described white, leukoplakia-like plaques in men who chewed kola for 10 and 2 years (the second also smoked heavily); in one man the plaque resolved after he stopped chewing. A cytology study linked kola chewing with more keratinization of the palate, highest in smokers who also chewed kola. See a dentist about any persistent white patch.
Pregnancy: EFSA considers caffeine from all sources up to 200 mg a day not a safety concern for the fetus, and the FDA advises talking to your provider if you are pregnant, trying to become pregnant or breastfeeding. A survey in Nigeria found kola use in pregnancy common, often in high quantities.
Caffeine content varies between nuts and products. A US analysis of 53 supplements listing a caffeine-containing ingredient, such as kola nut or guarana, found 1 to 829 mg of caffeine a day at the maximum label dose; check the label for the caffeine amount.
A safety review could not define a no-observed-adverse-effect level for repeated intake of kola extract; its safety record rests on its caffeine content and a long history of use.

Important Drug interactions

Halofantrine (an antimalarial): in a crossover study in 15 healthy men, 12.5 g of kola nut taken with the drug lowered its peak blood level by about 45% and total exposure by about a third. The authors advise caution when drugs are taken with caffeine-containing foods; ask a pharmacist before taking kola with any medicine.
Drug metabolism: in Gambian villagers, cola nut use was linked to a longer half-life of antipyrine, a marker drug for liver metabolism; this was one observational study and has not been confirmed in a controlled trial. Effects on other medicines are unknown.
Caffeine interactions: kola's caffeine carries the same interactions as caffeine itself (see our caffeine page), and the FDA notes that some medications make people more sensitive to caffeine.
Other caffeine sources: coffee, tea, energy drinks, guarana and pre-workout products add to kola's caffeine. Count them all toward your daily total, and ask your prescriber before combining kola with stimulant medication.

Frequently asked questions about Kola Nut (Cola nitida)

How much caffeine is in kola nut?

One analysis of three Nigerian kola types found 18 to 24 g of caffeine per kg of nut, an estimated 18 to 24 mg per gram (the abstract does not say fresh or dry weight). At that level, the 12.5 g serving used in one human study would supply roughly 225 to 300 mg by our estimate. Fresh and dried nuts, extracts and supplements vary, so check the label for the caffeine amount.

How is kola nut different from guarana?

Both are caffeine-rich seeds, but they come from different plants: kola from West African Cola trees, guarana from an Amazonian climbing plant. Guarana has a handful of small human trials on reaction time and exercise; kola nut has none on those outcomes. Both add to your daily caffeine total.

Has kola nut been tested in clinical trials?

Not for energy, focus, exercise or weight. The only controlled human study gave 12.5 g of kola nut with an antimalarial drug to measure drug levels. Other human research consists of surveys, case reports and observational studies, so any stimulant effect is inferred from its caffeine.

Is kola nut the same as bitter kola?

No. Bitter kola is the seed of a different tree, Garcinia kola, with its own separate research. This page covers only the caffeine-containing kola nut from Cola nitida and Cola acuminata.

What is Kola Nut?

Kola nut is the seed of Cola nitida and Cola acuminata, evergreen trees native to West Africa, where the bitter nut is chewed during work and social life and offered as a sign of respect.

What is Kola Nut used for?

NutraSmarts does not list Kola Nut under a health category. What the research covers: Laboratory analysis of white and red Cola nitida and Cola acuminata nuts from Nigeria found 18 to 24 g of caffeine per kg, an estimated 18 to 24 mg per gram (the abstract does not say fresh or dry weight), so by our arithmetic 5 g of nut wo…

What is the recommended dosage of Kola Nut?

No dose of kola nut has been tested in people for energy, focus, exercise or weight. The one controlled human study gave a single 12. Always follow the product label and check with a healthcare provider for personal advice.

Is Kola Nut safe, and does it have side effects?

Side effects and cautions reported for Kola Nut include: Kola's caffeine can cause what the FDA lists for too much caffeine: increased heart rate, palpitations, high blood pressure, insomnia, anxiety, jitters, upset stomach, nausea and headache. It may also interact with some medications. Kola Nut is not right for everyone, so check with a healthcare provider first if you are pregnant or breastfeeding, have a medical condition, or take prescription medication.

Does Kola Nut interact with any medications?

Possible interactions include: Halofantrine (an antimalarial): in a crossover study in 15 healthy men, 12.5 g of kola nut taken with the drug lowered its peak blood level by about 45% and total exposure by about a third. If you take prescription medication, check with a pharmacist or doctor before using it.

How strong is the scientific evidence for Kola Nut?

NutraSmarts rates the evidence for Kola Nut as Preliminary (1 out of 5). It is backed by 5 study summaries and 15 cited references summarized on this page. A higher rating reflects more, larger, and better-designed human studies.

References(15 citations)

Evidence ratings on NutraSmarts are based on the totality of human clinical research, with emphasis on randomized controlled trials, meta-analyses, and systematic reviews. The references below directly support claims made throughout this page.

  1. Kolade YT, Babalola CP, Olaniyi AA, Scriba GK. Effect of kolanut on the pharmacokinetics of the antimalarial drug halofantrine. Eur J Clin Pharmacol. 2008;64(1):77-81. doi: 10.1007/s00228-007-0387-0.PubMedUsed to support: Randomized Latin-square crossover in 15 healthy men: a single 500 mg dose of halofantrine taken with 12.5 g of kola nut gave lower peak levels (179 to 98 ng/ml) and lower total exposure (AUC 17,450 to 11,821 ng x h/ml) than the drug alone, with similar falls for its active metabolite; time to peak and half-life did not change. The authors propose complex formation during absorption and advise caution when drugs are taken with caffeine-containing foods.
  2. Adedapo AD, Ojji DB, Adedapo KS, Kolade Y, Babalola CP. Comparative cardiac effects of antimalarial drug halofantrine with or without concomitant administration of kolanut or fluconazole in healthy volunteers. Afr Health Sci. 2023;23(1):262-269. doi: 10.4314/ahs.v23i1.28.PubMedUsed to support: ECG report from the same 2003 to 2004 Ibadan study as the halofantrine pharmacokinetic paper (18 healthy men in a crossover of halofantrine alone, with kola nut, or with fluconazole). The PR interval shortened slightly with halofantrine alone and with kola; QTc rose slightly in all three arms at 6 hours without statistical significance, although the abstract concludes that kola significantly decreased the cardiac effect of halofantrine. The full text gives the kola dose as 12.5 mg (the earlier paper says 12.5 g) and its baseline table lists group sizes that do not match an 18-person crossover. There was no kola-only arm.
  3. Atawodi SE, Pfundstein B, Haubner R, Spiegelhalder B, Bartsch H, Owen RW. Content of polyphenolic compounds in the Nigerian stimulants Cola nitida ssp. alba, Cola nitida ssp. rubra A. Chev, and Cola acuminata Schott & Endl and their antioxidant capacity. J Agric Food Chem. 2007;55(24):9824-8. doi: 10.1021/jf0721038.PubMedUsed to support: Laboratory analysis of three Nigerian kola types (Cola nitida white and red, Cola acuminata): caffeine 18 to 24 g/kg, (+)-catechin 27 to 37 g/kg, (-)-epicatechin 20 to 21 g/kg, procyanidin B1 15 to 19 g/kg and procyanidin B2 7 to 10 g/kg. Extracts showed antioxidant capacity in test-tube assays. No human testing.
  4. Burdock GA, Carabin IG, Crincoli CM. Safety assessment of kola nut extract as a food ingredient. Food Chem Toxicol. 2009;47(8):1725-32. doi: 10.1016/j.fct.2009.04.019.PubMedUsed to support: Safety review by a food-regulatory consultancy: kola nut extract, from Cola nitida or Cola acuminata seeds, is used as a food flavoring with estimated intake of 0.69 mg/kg/day; caffeine and theobromine are its two important constituents; its pharmacological and toxicological properties parallel those of a roughly equivalent dose of caffeine; a no-observed-adverse-effect level for repeated intake cannot be defined from available data; it cites a long history of use in cola-type beverages and of the whole nut.
  5. Starin D. Kola nut: so much more than just a nut. J R Soc Med. 2013;106(12):510-2. doi: 10.1177/0141076813507708.PubMedUsed to support: Essay on kola in West African life: the nut is chewed by laborers and at social gatherings, given as a sign of respect and offered in ceremonies; it has been credited with relieving fatigue, hunger and thirst and with many traditional remedies, and the author notes that many of these claims are clearly exaggerated. Kola extract went into early cola drinks. Not a clinical study.
  6. Atiba FA, Popoola OA, Odukogbe AA, Ihunwo AO. Prevalence and consumption pattern of kolanut among pregnant women in Ibadan metropolis. Sci Rep. 2023;13(1):14422. doi: 10.1038/s41598-023-41754-6.PubMedUsed to support: Cross-sectional survey of 478 pregnant women in Ibadan, Nigeria: 33.9% reported kola use during pregnancy and 29.3% in the current pregnancy; among current users 39.3% used it frequently and 32.9% in high quantities, and 93.7% used it to prevent spitting, nausea and vomiting. Measures use, not safety or benefit.
  7. Holcombe C, Kaluba J, Lucas SB. Non-ulcer dyspepsia in Nigeria: a case-control study. Trans R Soc Trop Med Hyg. 1991;85(4):553-5. doi: 10.1016/0035-9203(91)90258-z.PubMedUsed to support: Case-control study of 40 patients with non-ulcer dyspepsia and 40 matched symptom-free volunteers in northern Nigeria, with endoscopy and biopsy: cola nut ingestion was the only statistically significant difference between the groups; gastritis and H. pylori were common in both. An association, not proof of cause.
  8. Al Ramil A, Almazrooa S, Binmadi N, Mawardi H. Oral changes associated with kolanut use: a report of 2 cases. Oral Surg Oral Med Oral Pathol Oral Radiol. 2020;130(1):e5-e9. doi: 10.1016/j.oooo.2020.04.004.PubMedUsed to support: Two case reports of contact stomatitis in men who chewed kola nut (for 10 and 2 years): white, leukoplakia-like plaques with hyperparakeratosis on biopsy; the second man also smoked 30 cigarettes a day. The lesion persisted in the man who kept chewing and resolved, with persistent redness, in the man who stopped. The authors call the premalignant potential unknown.
  9. Fraser HS, Bulpitt CJ, Kahn C, Mould G, Mucklow JC, Dollery CT. Factors affecting antipyrine metabolism in West African villagers. Clin Pharmacol Ther. 1976;20(3):369-76. doi: 10.1002/cpt1976203369.PubMedUsed to support: Observational study in 49 healthy Gambian adults: saliva antipyrine half-life averaged 13.6 hours; sex, cola nut consumption, hemoglobin in women and height in men were independent predictors, and cola nut consumption was linked to a longer half-life. Together these factors explained 36% of the variation.
  10. Andrews KW, Schweitzer A, Zhao C, Holden JM, Roseland JM, Brandt M, Dwyer JT, Picciano MF, Saldanha LG, Fisher KD, Yetley E, Betz JM, Douglass L. The caffeine contents of dietary supplements commonly purchased in the US: analysis of 53 products with caffeine-containing ingredients. Anal Bioanal Chem. 2007;389(1):231-9. doi: 10.1007/s00216-007-1437-2.PubMedUsed to support: USDA laboratory analysis of 53 US supplements listing a caffeine-containing ingredient such as guarana, yerba mate, kola nut or green tea extract: caffeine ranged from 1 to 829 mg a day at the maximum label dose; of the 28 products with a labeled caffeine amount, 25 (89%) were within 16% of the claim.
  11. Salahdeen HM, Omoaghe AO, Isehunwa GO, Murtala BA, Alada AR. Effects of chronic administration of ethanolic extract of kolanut (Cola nitida) and caffeine on vascular function. Afr J Med Med Sci. 2014;43(1):17-27..PubMedUsed to support: Rat study: the kola extract tested at 51% caffeine by GC-MS. Over six weeks, kola extract and caffeine both lowered body weight and raised mean arterial blood pressure, and the authors concluded that kola's effects on blood vessel function are due to its caffeine. Animal work only.
  12. Odukoya O, Roberts T, Aroll G. A cytologic study of the effect of Kolanut on the keratinization of the palatal mucosal of Nigerian smokers. Afr Dent J. 1990;4(1-5):1-5..PubMedUsed to support: Cytology study of the palate lining in 96 Nigerian men aged 17 to 65 grouped as smokers who chewed kola, smokers, kola chewers and non-users: smoking and kola chewing significantly influenced keratinization, which ranked smokers plus kola above smokers above kola chewers above non-users. The authors suggest kola potentiates smoking-related keratinization.
  13. Maillard C, Babadjamian A, Balansard G, Ollivier B, Bamba D. Study of Caffein - Catechin Association in Lyophilized Fresh Seeds and in Stabilized Extract of Cola nitida. Planta Med. 1985;51(6):515-7. doi: 10.1055/s-2007-969579.PubMedUsed to support: Laboratory study: the share of caffeine bound to catechin by hydrogen bonding ranged from 0% in dried kola seeds to 91% in freeze-dried fresh seeds and stabilized extract. The authors suggest this may explain differing effects of fresh and dried seeds; not tested in people.
  14. U.S. Food and Drug Administration. Spilling the Beans: How Much Caffeine is Too Much? FDA Consumer Updates. 2024;Online consumer update, content current as of August 28, 2024..SourceUsed to support: Not PubMed-indexed (FDA consumer update). Cites 400 mg a day as an amount not generally associated with negative effects for most adults; advises people who are pregnant, trying to become pregnant or breastfeeding to talk to their provider; lists increased heart rate, palpitations, high blood pressure, insomnia, anxiety, jitters, upset stomach, nausea and headache as signs of too much caffeine; notes some conditions and medications increase sensitivity; reports toxic effects such as seizures with rapid intake of around 1,200 mg.
  15. European Food Safety Authority (EFSA). Caffeine EFSA topic page. 2015;Summary of the EFSA NDA Panel Scientific Opinion on the safety of caffeine, published 27 May 2015 (EFSA Journal 13(5):4102, doi: 10.2903/j.efsa.2015.4102); topic page accessed 2026..SourceUsed to support: Not PubMed-indexed (EFSA topic page). Names the kola nut as a natural caffeine source; states that single doses up to 200 mg (about 3 mg/kg) and daily intakes up to 400 mg (about 5.7 mg/kg) do not raise safety concerns for healthy adults other than pregnant women, that up to 200 mg a day from all sources does not raise safety concerns for the fetus, and proposes 3 mg/kg a day for children and adolescents.