1. Introduction: The Growing Burden of Diabetes in Nigeria
Diabetes mellitus has emerged as one of the most significant non-communicable disease challenges facing Nigeria and the African continent. Currently, over 3.6 million adults in Nigeria have diabetes, with an estimated annual treatment cost of US$500 per patient. This burden is compounded by the fact that approximately 75% of adults with diabetes live in low- and middle-income countries, where healthcare access remains limited and out-of-pocket expenses consume a substantial portion of household income.
The challenge of managing diabetes in Nigeria is multifaceted. Many patients spend more than 25% of their monthly income on healthcare, creating a significant economic burden that drives many toward alternative and more affordable treatment options. This economic reality, combined with cultural factors and the deep-rooted tradition of herbal medicine, has resulted in a healthcare landscape where traditional and orthodox medicines are frequently used side by side.
The World Health Organization (WHO) estimates that approximately 88% of the world’s population now uses traditional medicine, and Nigeria reflects this trend with a particularly strong reliance on herbal remedies. For many Nigerians, medicinal plants are not just alternatives but the first line of treatment, especially in rural areas where formal healthcare infrastructure may be limited.
This review synthesizes available literature on Nigerian medicinal plants utilized for diabetes management, their modes of administration, scientific evidence supporting their use, and the broader context of complementary and holistic approaches to diabetes care.
2. Prevalence of Herbal Medicine Use in Diabetes Management
2.1 Extent of Usage
Multiple studies across Nigeria have documented the widespread use of herbal medicines among diabetic patients, revealing consistent patterns of usage:
| Study Location | Herbal Medicine Usage Rate | Key Findings |
| South-Eastern Nigeria (Teaching Hospitals) | 75.4% | Most patients use TMPs concurrently with prescription medicines, often without doctor’s knowledge |
| Jos Metropolis (North Central) | 58.9% | Common remedies include Moringa oleifera, Vernonia amygdalina, and Allium sativum |
| North Central Nigeria (Outpatient Clinic) | 40.1% | Moringa was the most used CAM (34.4%); CAM users had higher rates of uncontrolled glycaemia |
The study conducted by Sylver-Francis and Pelkonen involving over 600 patients found that approximately 75% of participants used traditional medicinal plants (TMPs) concurrently with their prescription medicines, demonstrating alarmingly high prevalence. Perhaps more concerning, most doctors were unaware of this concurrent use, as patients often did not disclose their herbal medicine practices. This lack of communication creates significant potential for adverse drug interactions and complications.
2.2 Demographic Factors Influencing Usage
Analysis of demographic patterns reveals that:
- Age: The oldest age groups (40 years and above) ranked highest in TMP usage, reflecting deeper knowledge and acceptance of traditional remedies among older populations
- Marital Status: Married participants showed greater interest in traditional medicine compared with unmarried groups
- Gender, Education, and Religion: Statistical analysis showed no significant association between participants’ gender, level of education, or religion and their usage of TMPs (P = 0.636; P = 0.533; P = 0.419 respectively)
2.3 Patients with Comorbid Conditions
The study revealed that patients suffering from both diabetes and hypertension tended toward TMP use more than those with just diabetes or hypertension alone. This finding is significant given the high comorbidity between these conditions and the potential for dual-acting medicinal plants to address both simultaneously.
3. Nigerian Herbal Remedies for Diabetes: Scientific Evidence
3.1 Ethnobotanical Surveys and Documented Species
Several comprehensive ethnobotanical surveys have documented the rich diversity of Nigerian plants used for diabetes management.
Oye Local Government, Ekiti State Survey (2025)
A survey of 150 respondents documented 27 plant species belonging to 15 families used for diabetes treatment. Prominent among them were:
| Plant Name | Common Name |
| Ageratum conyzoides | Goat weed |
| Allium ascalonicum | Shallot |
| Allium sativum | Garlic |
| Carica papaya | Pawpaw |
| Rauvolfia vomitoria | African snakeroot |
| Aframomum meleguata | Alligator pepper |
| Momordica charantia | Bitter melon |
| Senna podocarpa | |
| Vernonia amygdalina | Bitter leaf |
Ikorodu, Lagos State Survey (2021)
A survey in Ikorodu revealed even greater diversity, documenting 94 different plant species and 44 polyherbal formulations. The most commonly used plants included:
| Plant | Frequency |
| Vernonia amygdalina | 15% |
| Ocimum gratissimum | 7% |
| Carica papaya and Citrus aurantifolia | 6% each |
| Momordica charantia and Bidens pilosa | 5% each |
3.2 Systematic Review of Plants with Experimental Evidence
A comprehensive systematic review identified 79 medicinal plant species in 49 families that displayed in vivo and/or in vitro pharmacological activities relevant to diabetes management . The most represented families were Apocynaceae, Cucurbitaceae, Rutaceae, and Euphorbiaceae.
A review by Idaguko and Adeniyi documented 35 Nigerian plants with putative anti-diabetic properties. The cellular mechanisms through which these natural agents exert their protective and therapeutic effects include:
- Antioxidative stress reduction
- Restricting the breakdown of glycogen
- Pancreatic β-cell regeneration
- Gluconeogenesis inhibition
- Anti-inflammatory effects
- Intracellular signal transduction pathways modulation
3.3 Promising Nigerian Antidiabetic Plants
3.3.1 Macaranga barteri
Macaranga barteri leaves, used in southwestern Nigeria, have demonstrated exceptional antidiabetic potential in scientific studies:
| Parameter | Result | Comparison |
| Total Phenolic Content | ICâ‚…â‚€ = 107.37 mg GAE/g | Highest among tested plants |
| Free Radical Scavenging | IC₅₀ = 6.58 μg/mL | Superior to ascorbic acid (IC₅₀ = 8.39 μg/mL) |
| α-Amylase Inhibition | IC₅₀ = 0.54 μg/mL | Superior to acarbose (IC₅₀ = 0.68 μg/mL) |
| Best Fraction (DCM) | IC₅₀ = 0.29 μg/mL | Highest α-amylase inhibition |
The major compounds identified included 3,5-dicaffeoylquinic acid, acteoside, kampferol-7-O-glucoside, and bastadin 11 . Researchers concluded that M. barteri leaves “could be a potent source of novel anti-diabetic agent” and that “Nigeria flora could be a veritable source of bioactive leads for drug development”.
3.3.2 Commonly Used Plants with Scientific Support
Studies evaluating four commonly used medicinal plants in Ogbomoso revealed significant antioxidant and antidiabetic properties:
| Plant | Total Flavonoids (mg/g QE) | DPPH Scavenging | Alpha-Amylase Inhibition | Alpha-Glucosidase Inhibition |
| Croton zambezicus | 170 (highest) | 89.6% | 21.1% | 80.0% |
| Albizia ferruginea | 16 | 31.7% | 10.5% | 85.3% |
| Markhamia tomentosa | 20 | 22.8% | 62.2% | 70.9% |
| Aspilia africana | 68 | 16.5% | 64.2% | 63.2% |
These extracts also inhibited lipid peroxidation with values ranging from 56% to 72% at maximum concentration (400 μg/mL) . The properties exhibited by these plants provide “scientific basis for their usage in traditional medicine for the treatment and management of diabetes mellitus” .
3.3.3 Matteuccia struthiopteris (Edible Fern)
A study on this edible wild plant from Cross River State, Nigeria, demonstrated:
- Rich phytochemical profile: Saponins (4.25 mg/100g), flavonoids (2.73 mg/100g), and terpenoids (2.23 mg/100g)
- Dose-dependent antidiabetic activity: Demonstrated through α-amylase and α-glucosidase inhibition assays
- Antioxidant and anti-inflammatory effects: Confirmed through multiple in vitro assays
While the extract showed lower potency than standard drugs, its “natural origin and multifunctional properties make it a valuable candidate for functional foods or herbal therapies”.
3.3.4 Rauvolfia-Citrus Tea (RC-Tea)
This formulation, made by boiling leaves of Rauvolfia vomitoria and fruits of Citrus aurantium (sour orange), has been studied for its antidiabetic effects in both animal models and humans with type 2 diabetes.
Standardized Preparation (per litre) :
| Component | Quantity |
| Dried R. vomitoria foliage | 40 g |
| Fresh C. aurantium fruits | 200 g |
| Final extract pH | 5 |
| Naringin (C. aurantium marker) | ~230 mg/L |
| Robinin (R. vomitoria marker) | ~25 mg/L |
Key Findings:
- Blood glucose normalization in genetic diabetic (BKS-db) mice and humans with T2D
- Reduction of ectopic lipid accumulation in treated animals
- Synergistic effect: The best antidiabetic outcome results from boiling the two plant materials together, as separate preparation and mixing resulted in hyperglycaemia, suggesting the importance of the traditional preparation method
3.4 Most Frequently Used Antidiabetic Plants in Nigeria
Based on available literature, the following plants consistently appear as the most frequently used for diabetes management in Nigeria:
| Plant Name | Common Name | Frequency | Preparation |
| Vernonia amygdalina | Bitter leaf | Highest (15% in Ikorodu) | Decoction, infusion |
| Allium sativum | Garlic | Very high (Jos study) | Raw, decoction |
| Moringa oleifera | Moringa | 34.4% (North Central study) | Infusion, powder |
| Ocimum gratissimum | Scent leaf | 7% (Ikorodu) | Decoction |
| Carica papaya | Pawpaw | 6% (Ikorodu) | Leaf infusion |
| Citrus aurantifolia | Lime | 6% (Ikorodu) | Infusion |
| Momordica charantia | Bitter melon | 5% (Ikorodu) | Decoction |
| Rauvolfia vomitoria | African snakeroot | Documented in multiple surveys | Decoction (RC-tea) |
| Bidens pilosa | Blackjack | 5% (Ikorodu) | Infusion |
3.5 Preparation Methods
Traditional preparations documented in surveys include:
| Method | Description | Common Usage |
| Decoction | Boiling plant material in water | Most common method for roots, barks, and tough leaves |
| Infusion | Steeping plant material in hot water (like tea) | Common for leaves and flowers |
| Maceration | Soaking in cold water or other solvents | Used for more delicate plant parts |
| Concoction | Mixing multiple plant preparations | Common for polyherbal formulations |
Duration of usage is typically between 2 weeks or more, with leaves forming the major part of plant materials used for herbal preparations.
4. Mechanisms of Action: How Nigerian Herbs Work
4.1 Alpha-Amylase and Alpha-Glucosidase Inhibition
Many Nigerian antidiabetic plants work by inhibiting carbohydrate-digesting enzymes:
- Alpha-amylase inhibition reduces the breakdown of starch into simpler sugars
- Alpha-glucosidase inhibition delays the absorption of carbohydrates from the intestine
These mechanisms are similar to those of modern drugs like acarbose, but with the potential for fewer side effects.
4.2 Antioxidant Activity
Oxidative stress plays a significant role in the pathogenesis of diabetes and its complications. Nigerian antidiabetic plants demonstrate:
- DPPH radical scavenging activity
- Hydroxyl radical scavenging activity
- Lipid peroxidation inhibition
- Rich flavonoid and phenolic content
4.3 Blood Glucose Normalization
Research on plants like the Rauvolfia-Citrus tea demonstrates direct blood glucose-lowering effects, likely through multiple pathways including:
- Enhanced glucose uptake by peripheral tissues
- Reduced hepatic glucose production
- Improved insulin sensitivity
- Possible pancreatic β-cell protection
5. Safety Concerns and Clinical Outcomes
5.1 Potential Risks
Despite the widespread use of herbal medicines, significant safety concerns exist. A study in Jos metropolis found:
| Outcome | CAM Users | Non-CAM Users | Statistical Significance |
| Higher hospitalizations | Yes | No | P < 0.05 |
| Higher hypoglycemia incidence | Yes | No | P < 0.05 |
| Fasting blood glucose | Unaffected | Unaffected | P > 0.05 |
The study in North Central Nigeria found that 71.4% of CAM users had uncontrolled fasting blood glucose, and those who did not use CAM were 1.95 times more likely to have controlled FBG (OR=1.95, CI=1.12-3.37, p<0.05).
5.2 Drug Interactions
The concurrent use of herbal remedies and conventional medications poses several risks:
- Hypoglycaemia: Herbal remedies may potentiate the effects of conventional antidiabetic drugs
- Direct toxicities: Some plants may have hepatotoxic or nephrotoxic effects
- Poor quality control: Variable potency and possible contamination
- Scanty or anecdotal directions: Lack of standardized dosing information
5.3 Patient Disclosure
One of the most concerning findings is that most doctors did not know—and were not told—about TMP use by their patients. This lack of disclosure prevents healthcare providers from:
- Assessing potential drug interactions
- Adjusting medication dosages appropriately
- Monitoring for adverse effects
- Providing informed guidance
6. Comparative Analysis: Herbal vs. Orthodox Therapy
| Aspect | Herbal Therapy | Orthodox Therapy |
| Active constituents | Multiple compounds, plant-based | Single or few synthetic compounds |
| Mechanism of action | Synergistic action of multiple constituents | Targeted, specific molecular action |
| Cost | Generally more affordable | Often expensive; >25% of income for many Nigerians |
| Accessibility | Widely available, locally sourced | Requires healthcare infrastructure and supply chains |
| Standardization | Variable, often lacking formal quality control | Strict pharmaceutical standards |
| Evidence base | Primarily traditional use; growing scientific validation | Extensive clinical trial evidence |
| Regulation | Limited NAFDAC oversight for many products | Strict regulatory oversight |
7. Indigenous Plant Status and Conservation
According to the International Union for Conservation of Nature (IUCN), the conservation status of several Nigerian antidiabetic plants has been assessed:
| Status | Species |
| Least Concern | Sterculia tragacantha, Newbouldia laevis, Solanum anomalum, Ficus exasperata, Raphia hookeri, Azadirachta indica, Syzygium cumini, Terminalia catappa, Solanum macrocarpon, Petersianthus macrocarpus, Xylopia aethiopica, Costus afer, Spondias mombin, Eucalyptus globulus, Parkia biglobosa, Persea americana, Anacardium occidentale, Vernonia amygdalina |
| Threatened | Hunteria umbellata, Vitex doniana |
| Vulnerable | Dacryodes edulis, Dennettia tripetala |
| Data Deficient | Phyllanthus amarus, Phyllanthus niruri, Telfairia occidentalis |
8. Holistic and Complementary Therapies
8.1 Dietary Interventions
Traditional dietary practices that support diabetes management include:
- Low glycemic index foods: Beans, legumes, unripe plantain
- Leafy vegetables: Bitter leaf, scent leaf, water leaf
- Herbal teas: Infusions of bitter leaf, moringa, or neem
- Fiber-rich meals: Traditional soups and stews with vegetables
8.2 Lifestyle Modifications
- Physical activity: Walking, farming, and traditional dances provide natural exercise
- Weight management: Traditional diets often support healthy weight
- Stress reduction: Prayer (used by almost all participants in the South-Eastern survey) , community support, and traditional relaxation practices
8.3 Integration with Conventional Care
The studies reviewed consistently recommend:
- Patient-centered approach to CAM use
- Health education on risks and benefits of concurrent use
- Community engagement to raise awareness
- Workshops for CAM providers on safety and referral
- Strengthening health systems to reduce reliance on unregulated CAM
- Doctor-patient communication about herbal medicine use
9. Recommendations for Safe Use
9.1 For Patients
| Recommendation | Rationale |
| Disclose all herbal medicine use to healthcare providers | Enables assessment of drug interactions and appropriate dosing |
| Use standardized products where available (e.g., NAFDAC-registered) | Reduces risk of contamination and ensures consistent potency |
| Monitor blood glucose regularly | Critical for detecting potential hypoglycaemia |
| Never replace prescribed medications without medical consultation | Herbal remedies should complement, not replace, conventional treatment |
| Report adverse effects immediately | Early detection of problems improves outcomes |
| Use herbal remedies from reputable sources | Reduces risk of adulteration |
9.2 For Healthcare Providers
- Ask about herbal medicine use during clinical consultations
- Provide evidence-based guidance on complementary therapies
- Monitor patients closely for drug interactions and adverse effects
- Document CAM use in patient records
- Consider further research on commonly used herbs
9.3 For Policymakers
- Strengthen NAFDAC regulation of herbal products
- Fund research on antidiabetic plants
- Develop integration guidelines for traditional and orthodox medicine
- Support conservation of threatened medicinal plant species
- Promote health education on safe CAM use
10. Research Gaps and Future Directions
10.1 Research Needs
| Area | Priority |
| Human clinical trials | Most evidence from in vitro and animal models; human safety and efficacy data needed |
| Long-term safety studies | Chronic use effects on liver, kidney, and other organs |
| Standardized dosing protocols | Defined dosing for herbal formulations |
| Drug interaction studies | Interactions between herbal remedies and metformin, sulfonylureas, insulin |
| Pharmacokinetic studies | Understanding absorption, distribution, metabolism, and elimination |
| Quality control methods | Developing affordable quality assurance methods |
| Mechanism of action studies | Cellular and molecular pathways of antidiabetic activity |
| Synergy studies | Understanding polyherbal combinations |
10.2 Opportunities
- GLP-1-based therapy analogues: Standardized herbal remedies that promote endogenous metabolic processes similar to GLP-1-based treatments could provide cheaper alternatives in low- and middle-income countries
- Dual-acting agents: Plants with both antidiabetic and antihypertensive properties present opportunities for development of therapies for concurrent management of both conditions
- Functional foods: Edible plants with demonstrated antidiabetic properties could be developed as functional foods for prevention and management
11. Conclusion
Diabetes mellitus poses a significant and growing health challenge in Nigeria, with over 3.6 million adults affected and substantial economic burden. The widespread use of herbal medicines for diabetes management reflects both cultural traditions and the economic realities facing many Nigerians.
The scientific literature reveals a rich diversity of Nigerian plants with antidiabetic potential. Notable findings include:
- 79 medicinal plant species with documented in vitro and/or in vivo pharmacological activities
- 35 plants with putative anti-diabetic properties documented in reviews
- 94 plant species and 44 polyherbal formulations documented in a single ethnobotanical survey
- Exceptional activity from Macaranga barteri, with α-amylase inhibition surpassing the standard drug acarbose
- Synergistic effects in formulations like the Rauvolfia-Citrus tea, where combined boiling produces better outcomes than separate preparation
However, the high prevalence of concurrent herbal and orthodox medicine use (40-75% across studies) raises significant safety concerns. Higher rates of hospitalizations, hypoglycemia, and uncontrolled glycaemia have been documented among herbal medicine users. The lack of disclosure to healthcare providers further compounds these risks.
The path forward requires :
- Acknowledging and respecting traditional knowledge while subjecting it to scientific scrutiny
- Strengthening regulatory oversight of herbal products
- Promoting open communication between patients and healthcare providers
- Investing in research on safety, efficacy, and mechanisms of action
- Developing integration strategies that combine the best of both systems
- Preserving and documenting indigenous knowledge before it is lost
As Nigeria continues its fight against diabetes, the careful integration of evidence-based traditional medicine into the healthcare system offers a promising path toward more accessible, affordable, and culturally appropriate diabetes care.
12. References
- Suleman NF. Ethnobotanical Survey on Medicinal Herbs Used in Treatment of Diabetes in Oye Local Government. Federal University Oye-Ekiti. 2025.
- David S, Oni CO, Ejila B, Alphonsus PN, Dayol MSA. Relationship between Complementary use of Herbal Medicines and Diabetes Mellitus Treatment Outcomes: A Cross-Sectional Study in Two Tertiary Healthcare Facilities in Jos Metropolis. International Journal of Innovative Science and Research Technology. 2024:923-929.
- Olakanmi FA, Adedosu OT, Ajala OA, James BA, Ebenezer FP, Idris AA. Evaluation of Antioxidant and Anti-Diabetic Potentials of the Ethyl Acetate Leaf Extracts of some Commonly used Medicinal Plants in Ogbomoso, Nigeria. International Journal of Innovative Science and Research Technology. 2024:1604-1609.
- Sylver-Francis RA, Pelkonen O. Medicinal plants as alternatives for the management of hypertension and diabetes in Nigeria: Analysis of the structured interview of Nigerian patients. Phytomedicine Plus. 2025;5(1):100708.
- Sylver-Francis RA, Simmonds MSJ, Pelkonen O. Systematic review for in vitro/in vivo activities of medicinal plants in Nigeria used for comorbid hypertension and diabetes. Journal of Medicinal Plants Research. 2025;19(7):112-145.
- Oko GE, Ogbonna OE, Agboola AR, Sunday UE, Bala FJ. In Vitro Antioxidants, Antidiabetic and Antiinflammatory Properties of Nigerian Matteuccia struthiopteris (Edible Fern). Research Square. 2025.
- Abu T, Adedayo AJ, Luma WS, Ogbole O. Potential Antidiabetic Effects by Alpha-Amylase Inhibition and Free Radical Scavenging Activity of Extracts from Five Medicinal Plants Used in Nigeria. Springer. 2024.
- De-Kaa NLP, et al. Effects of Complementary and Alternative Medicine Use on Fasting Blood Glucose Among Adult Type 2 Diabetics Attending General Outpatient Clinic in North Central Nigeria: Any Benefits? West African Journal of Medicine. 2025;42(3):231-239.
- Campbell-Tofte J, Mu H, Winther K, Mølgaard P, Belin N, Josefsen K. Standardization parameters and synergism of source plant materials for the antidiabetic efficacy of the Rauvolfia-Citrus tea. Fitoterapia. 2024;176:106004.
- Idaguko CA, Adeniyi MJ. Indigenous Antidiabetic Medicinal Plants Used in Nigeria: A Review. Asian Plant Research Journal. 2023;11(6):81-97.
- Awote OK, Ojekale AB, Kazeem MI, Bankole HA, Igbalaye JO. Ethnobotanical Survey of Medicinal Plants Used in the Management of Diabetes Mellitus in Ikorodu, Nigeria. LASU Journal of Environmental Science and Technology. 2021.