The Sunlight Experiment

Condition

Diabetes

Diabetes is a metabolic disorder characterized by chronically elevated blood glucose due to deficient insulin secretion, insulin resistance, or both.

Endocrine System Metabolic System
Justin Cooke, BHSc Clinical Herbalist · July 14, 2026

Diabetes mellitus is a group of metabolic disorders in which blood glucose stays chronically elevated because the body either cannot make enough insulin, cannot use it effectively, or both. Sustained high blood sugar gradually damages blood vessels and nerves, which is what drives most of the long-term complications. Herbal and nutritional support aims to improve insulin sensitivity, blunt post-meal glucose spikes, and protect the tissues most vulnerable to hyperglycemia — always alongside, never instead of, proper medical monitoring.

Presentation

Types & Variants

Diabetes is not a single disease but a family of conditions that share the endpoint of high blood glucose:

  • Type 1 — an autoimmune destruction of the insulin-producing beta cells of the pancreas. It usually appears early in life, accounts for roughly 10% of cases, and creates an absolute dependence on injected insulin.
  • Type 2 — by far the most common form, driven by insulin resistance that slowly progresses toward relative insulin deficiency. It is strongly tied to lifestyle and, caught early, is often manageable with diet and activity before medication becomes necessary.
  • LADA (latent autoimmune diabetes in adults) — a slowly developing beta-cell autoimmunity in adulthood, frequently misclassified as type 2 at first because of its gradual onset.
  • MODY (maturity-onset diabetes of the young) — a genetically driven form without autoimmune features, clinically close to type 2.
  • Gestational diabetes — glucose intolerance that emerges in pregnancy as maternal insulin resistance rises. It usually resolves after delivery but signals a higher lifetime risk of type 2.
  • Secondary diabetes — hyperglycemia caused by a separate problem, such as pancreatic disease (pancreatitis, cystic fibrosis), long-term corticosteroid therapy, or hormone-secreting disorders like acromegaly or Cushing’s.

Overview

General Pathology

Blood glucose is normally held within a tight range by insulin, which moves sugar out of the blood and into cells. In type 1 diabetes, immune-mediated loss of the pancreatic beta cells removes that signal almost entirely, so glucose accumulates in the blood while the cells starve. In type 2 diabetes, cells become progressively less responsive to insulin; the pancreas compensates by secreting more of it (hyperinsulinemia), but over years this demand exhausts beta-cell function and glucose control fails.

The harm done by diabetes is largely vascular. Persistent hyperglycemia damages the small vessels — microvascular disease, behind diabetic nephropathy, retinopathy, and peripheral neuropathy — and accelerates large-vessel disease, raising the risk of stroke, coronary artery disease, and peripheral arterial disease.

Presentation differs by type. Type 1 often arrives acutely, with excessive thirst, frequent urination, marked weight loss, hunger, fatigue, and blurred vision, and can escalate to diabetic ketoacidosis if untreated. Type 2 develops quietly and may be asymptomatic for years before thirst, fatigue, blurred vision, slow-healing wounds, recurrent infections, and tingling or numbness in the hands and feet appear. Diagnosis rests on an HbA1c of 6.5% or higher, a fasting blood glucose over 7.0 mmol/L, or a prediabetic range of roughly 5.5–6.9 mmol/L.

Materia Medica

Materia Medica

The herbs used for diabetes range from meta-analysed trials to rodent work and tradition. None of them is a substitute for professional care.

Evidence: Strong — human RCT / meta-analysis Moderate — small or mixed human Preclinical — animal / in-vitro / mechanism Traditional only — no trial No benefit — studied, negative result
Asian GinsengPanax ginsengStrong

Blood-glucose control is ginseng’s most robust human signal. A meta-analysis of 16 RCTs (n≈770) found ginseng significantly reduced fasting blood glucose (mean difference −0.31 mmol/L), though it did not move fasting insulin, HbA1c or HOMA-IR overall 62Reference 62Shishtar et al. · 2014Meta-analysisThe effect of ginseng (the genus Panax) on glycemic control — systematic review and meta-analysis of randomised controlled trialsView study →; a later meta-analysis of 20 RCTs in prediabetes/type-2 diabetes reported significant drops in fasting glucose, total cholesterol, IL-6 and HOMA-IR, clearer at ≥2 g/day 63Reference 63Naseri et al. · 2022Meta-analysisThe efficacy of ginseng (Panax) on human prediabetes and type 2 diabetes mellitus — systematic review and meta-analysisView study →, with a single G115 dose lowering glucose acutely 64Reference 64Reay et al. · 2005RCTSingle doses of Panax ginseng (G115) reduce blood glucose levels and improve cognitive performance during sustained mental activity — RCTView study →, via enhanced insulin secretion, peripheral glucose uptake and reduced intestinal glucose absorption.

Effects are small, largely on fasting glucose rather than HbA1c, trials are short with heterogeneous/proprietary extracts, and there are no long-term complication outcomes.

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CoffeeCoffea arabicaStrong

Coffee’s most robust, dose-dependent association: a dose-response meta-analysis of 28 prospective cohorts (1,109,272 participants) found type 2 diabetes risk fell stepwise with intake — RR 0.92 → 0.67 across 1–6 cups/day — and the protection held for both caffeinated (RR 0.91/cup) and decaffeinated (RR 0.94/cup), pointing to chlorogenic acid and glucose handling rather than caffeine 38Reference 38Ding et al. · 2014Meta-analysisCaffeinated and decaffeinated coffee consumption and risk of type 2 diabetes: a systematic review and dose-response meta-analysisView study →; both 2017 umbrella reviews rank it a top-confidence coffee association 39,40Reference 39Poole et al. · 2017Meta-analysisCoffee consumption and health: umbrella review of meta-analyses of multiple health outcomes — systematic reviewView study →Reference 40Grosso et al. · 2017Systematic reviewCoffee, caffeine, and health outcomes: an umbrella review — systematic reviewView study →. Entirely observational, no feasible long-term RCT, and one Mendelian-randomization synthesis flagged a positive genetic association with T2D, so causal direction is not fully settled 41Reference 41Pham et al. · 2025Systematic reviewCoffee and health outcomes: a systematic review of Mendelian randomisation studies — systematic reviewView study →.

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FenugreekTrigonella foenum-graecumStrong

Multiple meta-analyses of RCTs in type 2 diabetes and prediabetes report significant reductions in fasting blood glucose, 2-hour post-load glucose and HbA1c, with a 2023 dose-response pooling of 29 RCTs putting the fasting-glucose fall at roughly 17 mg/dL 55,56,57,58Reference 55Shabil et al. · 2023Meta-analysisEffect of Fenugreek on Hyperglycemia: A Systematic Review and Meta-AnalysisView study →Reference 56Kim et al. · 2023Meta-analysisThe Effect of Fenugreek in Type 2 Diabetes and Prediabetes: A Systematic Review and Meta-Analysis of Randomized Controlled TrialsView study →Reference 57Gong et al. · 2016Meta-analysisEffect of fenugreek on hyperglycaemia and hyperlipidemia in diabetes and prediabetes: A meta-analysisView study →Reference 58Fakhr et al. · 2023Meta-analysisEffects of fenugreek supplementation on the components of metabolic syndrome: A systematic review and dose-response meta-analysis of randomized clinical trialsView study →. Two mechanisms converge: viscous galactomannan fibre slowing carbohydrate absorption, and 4-hydroxyisoleucine stimulating glucose-dependent insulin secretion. Caveats are heterogeneity, small geographically clustered trials (largely India/Iran) and high risk of bias; the effective doses are whole/defatted seed in grams (5–100 g/day), not the milligram testosterone extracts.

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GynostemmaGynostemma pentaphyllumStrong

Blood-sugar control is gynostemma’s best-evidenced use. A 12-week RCT in drug-naïve type-2 diabetics drinking 6 g/day authenticated jiaogulan tea cut fasting plasma glucose ~3.0 mmol/L and HbA1c ~2 points versus placebo, with reduced HOMA-IR and no hypoglycaemia 85Reference 85Huyen et al. · 2010RCTAntidiabetic effect of Gynostemma pentaphyllum tea in randomly assigned type 2 diabetic patients — randomised controlled trialView study →; a 2026 meta-analysis of eight studies (584 patients) pooled −0.79 mmol/L fasting glucose and −1.01% HbA1c, and an independent systematic review matched the ~−1% HbA1c effect 86,87Reference 86Wang et al. · 2026Meta-analysisEfficacy and mechanisms of Gynostemma pentaphyllum in glycemic control — meta-analysis with reviewView study →Reference 87Chattopadhyay et al. · 2022Meta-analysisEffectiveness and safety of Ayurvedic medicines in type 2 diabetes mellitus — systematic review and meta-analysisView study →. The mechanism is multi-target (AMPK-driven glucose uptake, suppressed hepatic output, improved insulin sensitivity) 86,88Reference 86Wang et al. · 2026Meta-analysisEfficacy and mechanisms of Gynostemma pentaphyllum in glycemic control — meta-analysis with reviewView study →Reference 88Nayyar et al. · 2023RCTGynostemma pentaphyllum increases exercise performance and alters mitochondrial respiration and AMPK in healthy males — randomised controlled trialView study →. Caveat: trials are small, short and mostly East-Asian, and no standardised gypenoside dose exists — tea and concentrated extract are not interchangeable.

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Milk ThistleSilybum marianumStrong

A 2016 systematic review/meta-analysis of five RCTs concluded silymarin significantly lowered fasting glucose and HbA1c in type 2 diabetes, anchored by a 2006 four-month double-blind RCT (n=51, silymarin 200 mg 3×/day) improving HbA1c, glucose and lipids versus placebo 95,96Reference 95Voroneanu L et al. · 2016Meta-analysisSilymarin in type 2 diabetes mellitus: a systematic review and meta-analysis of randomized controlled trials — systematic review and meta-analysisView study →Reference 96Huseini HF et al. · 2006RCTThe efficacy of Silybum marianum (silymarin) in the treatment of type II diabetes: a randomized, double-blind, placebo-controlled clinical trial — randomised placebo-controlled trialView study →. Later meta-analyses extend this to insulin resistance and oxidative-stress markers 97,98Reference 97Hadi A et al. · 2018Meta-analysisThe effects of silymarin supplementation on metabolic status and oxidative stress in patients with type 2 diabetes mellitus: a systematic review and meta-analysis of clinical trials — systematic review and meta-analysisView study →Reference 98Soleymani S et al. · 2022Meta-analysisThe effects of silymarin on the features of cardiometabolic syndrome in adults: a systematic review and meta-analysis — systematic review and meta-analysisView study →. Caveat: trials are small, short and concentrated in a few (mostly Iranian) groups, with no large multicentre confirmation and no hard endpoints.

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NigellaNigella sativaStrong

Blood-sugar control is nigella’s strongest indication. A meta-analysis of 17 RCTs found the seed lowered fasting plasma glucose (~9.9 mg/dL), postprandial glucose (~14.8 mg/dL) and HbA1c (~0.57 points), with seed oil outperforming powder; an updated meta-analysis and the 2025 GRADE-assessed synthesis of 82 RCTs confirmed the direction 99,100,101,102Reference 99Askari G et al. · 2019Meta-analysisEffect of Nigella sativa (black seed) supplementation on glycemic control — systematic review and meta-analysis of clinical trialsView study →Reference 100Shirvani S et al. · 2024Meta-analysisThe effect of Nigella sativa supplementation on glycemic status in adults — updated systematic review and meta-analysis of randomized controlled trialsView study →Reference 101Daryabeygi-Khotbehsara R et al. · 2017Meta-analysisNigella sativa improves glucose homeostasis and serum lipids in type 2 diabetes — systematic review and meta-analysisView study →Reference 102Jafari A et al. · 2025Meta-analysisDoes Nigella sativa supplementation improve cardiovascular disease risk factors? A GRADE-assessed systematic review and dose-response meta-analysis of 82 randomized controlled trialsView study →, mechanistically via thymoquinone improving insulin sensitivity and β-cell function through Nrf2 103Reference 103Talebi M et al. · 2021ReviewBiological and therapeutic activities of thymoquinone — focus on the Nrf2 signaling pathway — reviewView study →. Reductions are real and reproducible but modest (~half an HbA1c point), heterogeneity is high, and no optimal standardised dose/duration is established.

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PsylliumPlantago ovataStrong

A meta-analysis of 35 RCTs across three decades found that in patients being treated for type 2 diabetes, psyllium taken before meals improved fasting blood glucose by −37 mg/dL and HbA1c by −0.97% — roughly a full percentage point 104Reference 104Gibb et al. · 2015Meta-analysisPsyllium fiber improves glycemic control proportional to loss of glycemic control: a meta-analysis of data in euglycemic subjects, patients at risk of type 2 diabetes mellitus, and patients being treated for type 2 diabetes mellitus — meta-analysisView study →. Benefit scaled with baseline loss of glycaemic control: no significant effect in healthy euglycaemic subjects, modest in pre-diabetes, largest in established T2DM. The gel slows gastric emptying and glucose diffusion to the gut wall, which is why pre-meal timing matters.

Much of the pooled data derives from a single manufacturer’s records. The effect is negligible in people with normal glucose, so psyllium is an adjunct rather than a therapy, and not a preventive for the euglycaemic.

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SteviaStevia rebaudianaStrong

Blood-sugar control is stevia’s best-supported indication. A 2024 systematic review/meta-analysis (26 studies, n=1439) found stevia significantly lowered blood glucose (WMD -3.84 mg/dL), with a second 2024 meta-analysis (12 RCTs, n=871) and earlier pooled work concurring 117,118,119Reference 117Zare et al. · 2024Meta-analysisEffect of stevia on blood glucose and HbA1C: a meta-analysis — systematic review, meta-analysisView study →Reference 118Bai et al. · 2024Meta-analysisEffect of steviol glycosides as natural sweeteners on glucose metabolism in adult participants — meta-analysisView study →Reference 119Onakpoya et al. · 2015Meta-analysisEffect of the natural sweetener steviol glycoside on cardiovascular risk factors: a systematic review and meta-analysis of randomised controlled trialsView study →; much of the acute benefit is simple sugar substitution — replacing a sucrose load with stevioside blunts the postprandial glucose/insulin rise 120,121Reference 120Anton et al. · 2010RCTEffects of stevia, aspartame, and sucrose on food intake, satiety, and postprandial glucose and insulin levels — randomised controlled trialView study →Reference 121Tey et al. · 2017RCTEffects of aspartame-, monk fruit-, stevia- and sucrose-sweetened beverages on postprandial glucose, insulin and energy intake — randomised controlled trialView study →.

The effect is modest and confined mainly to fasting glucose — HbA1c and insulin are largely unchanged and certainty is graded low, so stevia helps manage, not treat, diabetes.

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TurmericCurcuma longaStrong

A landmark 9-month RCT in 240 prediabetic adults saw none of the curcumin group progress to type 2 diabetes vs 16.4% on placebo, with improved β-cell function and insulin resistance 129Reference 129Chuengsamarn S et al. · 2012RCTCurcumin extract for prevention of type 2 diabetes — randomized, double-blind, placebo-controlled trialView study →; a 2024 meta-analysis of 18 RCTs (n=1,382 T2DM) found curcumin lowered fasting glucose (~11.5 mg/dL) and HbA1c (~0.54%) 130Reference 130Mokgalaboni K et al. · 2024RCTCurcumin Attenuates Hyperglycemia and Inflammation in Type 2 Diabetes Mellitus: Quantitative Analysis of Randomized Controlled TrialsView study →, and fasting blood sugar was rated high certainty in a 103-RCT overview 131Reference 131Jafari A et al. · 2024Meta-analysisCurcumin on Human Health: A Comprehensive Systematic Review and Meta-Analysis of 103 Randomized Controlled TrialsView study →. Effect sizes are modest and formulation-dependent — curcumin is an adjunct, not a replacement for glucose-lowering therapy, and prevention rests on a single (large) trial.

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Yerba MatéIlex paraguariensisStrong

Blood-sugar control is yerba maté’s most credible human indication. A 2025 systematic review and meta-analysis of 13 RCTs found maté significantly lowered postprandial glucose (−12.76 mg/dL), HbA1c (−0.37%) and the HOMA-IR index (−0.24) in pre-diabetic subjects 134Reference 134Li et al. · 2025Meta-analysisYerba Maté and its impact on glycemic control and metabolic health: a systematic review and meta-analysis of RCTsView study →, and a 60-day RCT in T2DM/pre-diabetic drinkers reported improved glycaemic control from roasted-leaf infusion, attributed to chlorogenic acid modulating glucose absorption and hepatic G6Pase 135Reference 135Klein et al. · 2011RCTMate tea (Ilex paraguariensis) improves glycemic and lipid profiles of type 2 diabetes and pre-diabetes individuals — randomized controlled trialView study →. Benefit concentrates in pre-diabetes/T2DM and postprandial (not fasting) measures — the meta-analysis found no effect on fasting glucose — and roasted vs. green preparation materially changes the result.

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American GinsengPanax quinquefoliusModerate

American ginseng reproducibly blunts postprandial glucose: crossover RCTs showed 3 g taken 40 minutes before a glucose challenge significantly reduced postprandial glycaemia in both non-diabetic and type 2 diabetic subjects 59Reference 59Vuksan et al. · 2000RCTAmerican ginseng (Panax quinquefolius L) reduces postprandial glycemia in nondiabetic subjects and subjects with type 2 diabetes mellitus — randomised controlled trialView study →, with the effect time-dependent (pre-loading required) but not dose-dependent across 1–3 g 60Reference 60Vuksan et al. · 2001RCTAmerican ginseng attenuates postprandial glycemia in a time-dependent but not dose-dependent manner in healthy individuals — randomised controlled trialView study →. A double-blind crossover trial (n=24, type 2 diabetics) using American ginseng as an add-on to standard therapy reported significant reductions in HbA1c (−0.29%) and fasting glucose (−0.71 mmol/L) plus lowered systolic BP and LDL-cholesterol, with an unchanged safety profile 61Reference 61Vuksan et al. · 2019RCTEfficacy and safety of American ginseng extract on glycemic control and cardiovascular risk factors in type 2 diabetes: a double-blind, randomized, cross-over clinical trial — randomised controlled trialView study →.

The effect is replicated, but samples are small, most of the work comes from one research group, and the pre-meal timing requirement complicates practical use. American ginseng adds to the glucose-lowering effect of insulin and oral hypoglycaemics.

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AmlaPhyllanthus emblicaModerate

Amla works more as an antioxidant adjuvant than a glucose-lowering therapy. Amla fruit powder at 1–3 g/day for 21 days significantly reduced fasting and post-prandial glucose in both healthy and type-2 diabetic volunteers, the higher doses also improving lipids 4Reference 4Akhtar et al. · 2011Effect of Amla fruit (Emblica officinalis Gaertn.) on blood glucose and lipid profile of normal subjects and type 2 diabetic patientsView study →, and the 2023 meta-analysis pooling glucose data reported a significant fall in fasting blood glucose alongside CRP 5Reference 5Setayesh et al. · 2023Meta-analysisThe impact of Emblica officinalis (Amla) on lipid profile, glucose, and C-reactive protein: a systematic review and meta-analysis of randomized controlled trialsView study →.

A systematic review maps the mechanisms for diabetic complications — improved insulin signalling, β-cell protection, reduced advanced-glycation-end-product accumulation 6Reference 6Huang et al. · 2021Potential effect of the tropical fruit Phyllanthus emblica L. for the prevention and management of type 2 diabetic complicationsView study →. In T2DM specifically, the standardised extract improved salbutamol-challenge endothelial function and oxidative markers over 12 weeks 7Reference 7Usharani et al. · 2013RCTEffects of Phyllanthus emblica extract on endothelial dysfunction and biomarkers of oxidative stress in patients with type 2 diabetes mellitus: a randomised, double-blind, controlled studyView study →.

The human glycaemic trials are small, short, and mostly use whole-fruit powder rather than the standardised extract, so the glucose and lipid evidence do not rest on the same preparation. Amla’s effect adds to that of antidiabetic medication.

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AshwagandhaWithania somniferaModerate

A 2020 meta-analysis reported restored blood glucose, HbA1c, insulin and lipid markers, but the pooled effect is dominated by in-vitro (6) and animal (13) studies against only five clinical ones, and the authors conclude the human data are too weak to support clinical use 10Reference 10Durg S et al. · 2020Meta-analysisWithania somnifera (Indian ginseng) in diabetes mellitus — a systematic review and meta-analysisView study →. The mechanism is plausible; the human evidence is sparse, old and uncontrolled.

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BarberryBerberis spp.Moderate

A meta-analysis of seven barberry RCTs (452 participants) reduced fasting insulin but did not consistently move fasting glucose or HbA1c 14Reference 14Safari et al. · 2020Meta-analysisThe effect of barberry (Berberis vulgaris L.) on glycemic indices — systematic review and meta-analysis of randomized controlled trialsView study →; the strong glycaemic results — HbA1c −0.73%, fasting glucose, HOMA-IR — belong to isolated berberine (46-trial meta-analysis 15Reference 15Guo et al. · 2021Meta-analysisThe effect of berberine on metabolic profiles in type 2 diabetic patients — systematic review and meta-analysis of randomized controlled trialsView study →, plus 16Reference 16Dong et al. · 2012Meta-analysisBerberine in the treatment of type 2 diabetes mellitus — systematic review and meta-analysisView study →) whose absorption differs from a whole-herb preparation.

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Bitter MelonMomordica charantiaModerate

Diabetes is the one bitter melon indication tested in humans. Several meta-analyses find modest reductions in fasting glucose, post-prandial glucose and HbA1c in T2DM/prediabetes 17,18,19Reference 17Peter et al. · 2019Meta-analysisMomordica charantia L. lowers elevated glycaemia in type 2 diabetes mellitus patients — systematic review and meta-analysisView study →Reference 18Zhang et al. · 2024Meta-analysisEffects of Momordica charantia L. supplementation on glycemic control and lipid profile in type 2 diabetes — meta-analysis of RCTsView study →Reference 19Mkhize et al. · 2025Meta-analysisEfficacy of Momordica charantia in glycaemic control and insulin resistance — a GRADE-adherent meta-analysis of RCTsView study →.

A Cochrane review and a 2024 GRADE meta-analysis found the evidence too sparse/low-quality to support a firm claim 20,21Reference 20Ooi et al. · 2012Systematic reviewMomordica charantia for type 2 diabetes mellitus — systematic reviewView study →Reference 21Laczkó-Zöld et al. · 2024Meta-analysisThe metabolic effect of Momordica charantia cannot be determined based on the available clinical evidence — meta-analysis of RCTsView study →, and the trials refuse to converge because no two use the same preparation (fruit vs seed vs leaf; juice vs powder vs extract). Effect is real but small, larger in prediabetes and with sustained dosing (a single acute dose does nothing 22Reference 22Kasbia et al. · 2009RCTNo effect of acute, single-dose oral Momordica charantia on glycemia, energy expenditure and appetite — randomised pilot study in non-diabetic overweight menView study →). The proposed mechanism is the insulin-mimetic action of charantin and polypeptide-p, plus AMPK, GLUT4 and PPARγ signalling.

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CacaoTheobroma cacaoModerate

Meta-analytic biomarker data suggest cocoa flavanols improve insulin sensitivity and fasting insulin, plausibly via epicatechin effects on nitric oxide plus in-vitro α-amylase/α-glucosidase inhibition 27,28Reference 27Lin X et al. · 2016Meta-analysisCocoa flavanol intake and biomarkers for cardiometabolic health: a systematic review and meta-analysis of randomised controlled trialsView study →Reference 28Oboh G et al. · 2014In vitroIn vitro studies on the antioxidant property and inhibition of alpha-amylase, alpha-glucosidase, and angiotensin-I-converting enzyme by polyphenol-rich extracts from cocoa (Theobroma cacao) beanView study →.

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Cassia CinnamonCinnamomum cassiaModerate

Cinnamon’s most-studied effect: a 2024 dose-response meta-analysis of 24 RCTs and a 2025 meta-analysis of 28 RCTs (3,054 patients) found significant falls in fasting blood glucose (~15 mg/dL), HOMA-IR and postprandial glucose in type 2 diabetes, via cinnamaldehyde-driven insulin signalling 33,34,35Reference 33Moridpour AH et al. · 2024Meta-analysisThe effect of cinnamon supplementation on glycemic control in patients with type 2 diabetes mellitus: an updated systematic review and dose-response meta-analysis of randomized controlled trials — [meta-analysis]View study →Reference 34Deyno S et al. · 2019Meta-analysisEfficacy and safety of cinnamon in type 2 diabetes mellitus and pre-diabetes patients: a meta-analysis and meta-regression — [meta-analysis]View study →Reference 35de Moura SL et al. · 2025Meta-analysisEffects of cinnamon supplementation on metabolic biomarkers in individuals with type 2 diabetes: a systematic review and meta-analysis — [meta-analysis]View study →.

HbA1c — the marker that matters for long-term outcomes — does not move reliably, a 2013 meta-analysis found no HbA1c effect with very high heterogeneity (I² up to 95%), and the 2012 Cochrane review judged the evidence insufficient 36,37Reference 36Allen RW et al. · 2013Meta-analysisCinnamon use in type 2 diabetes: an updated systematic review and meta-analysis — [meta-analysis]View study →Reference 37Leach MJ · 2012Systematic reviewCinnamon for diabetes mellitus — [systematic review]View study →. Cinnamon is a modest adjunct, not a replacement for glucose-lowering medication; most trials do not specify the species.

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CoptisCoptis chinensisModerate

Meta-analyses of isolated berberine in type 2 diabetes report clinically meaningful reductions in fasting glucose (~0.82 mmol/L) and HbA1c (~0.63%) across 37 RCTs (3,048 patients), scaling with baseline hyperglycaemia and without excess hypoglycaemia 42,43Reference 42Xie et al. · 2022Meta-analysisGlucose-lowering effect of berberine on type 2 diabetes — systematic review and meta-analysis of randomised controlled trialsView study →Reference 43Lan et al. · 2015Meta-analysisMeta-analysis of the effect and safety of berberine in the treatment of type 2 diabetes mellitus, hyperlipaemia and hypertension — meta-analysisView study →. At the herb level, a meta-analysis of 33 RCTs (2,846 patients) of Coptis-containing formulas added to metformin found further improvement in fasting glucose, HbA1c and HOMA-IR, but rated the evidence moderate-to-low for methodological quality 44Reference 44Pan et al. · 2022Meta-analysisSystematic review and meta-analysis of Coptis chinensis Franch.-containing traditional Chinese medicine as an adjunct therapy to metformin in type 2 diabetes — systematic review and meta-analysisView study →. No RCT tests Coptis rhizome as standalone therapy; Coptis polysaccharides add a separate antiglycation mechanism in mice 45Reference 45Yang et al. · 2016In vitroCoptis chinensis polysaccharides inhibit advanced-glycation-end-product formation — in vitro and diabetic mouse modelView study →.

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Globe ArtichokeCynara scolymusModerate

The pooled results are mixed. A meta-analysis of 9 RCTs found significantly lower fasting glucose (~5.3 mg/dL) but no change in fasting insulin, HOMA-IR or HbA1c 8Reference 8Jalili C et al. · 2020Meta-analysisEffects of Cynara scolymus L. on glycemic indices — systematic review and meta-analysis of randomised clinical trialsView study →, while the 2025 synthesis reported reduced insulin and HOMA-IR but no fasting-glucose or HbA1c effect — a partly contradictory picture across pooled analyses 9Reference 9Jafari A et al. · 2025Artichoke and cardiometabolic health — systematic and meta-analytic synthesisView study →. The chlorogenic-acid / glucose-6-phosphatase claim is constituent-level inference, not shown for the whole herb in humans. Signal is small and endpoints disagree; no consistent effect on the markers that matter most for diabetes.

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GuamuraCecropia mexicanaModerate

Glucose lowering is the genus’s best-evidenced action, but the evidence comes from C. obtusifolia, not C. mexicana. The single human study was open-label, uncontrolled and small (32 weeks, fasting glucose + HbA1c down) 79Reference 79Revilla-Monsalve et al. · 2007Clinical trialHypoglycemic effect of Cecropia obtusifolia Bertol aqueous extracts on type 2 diabetic patients — clinical trialView study →. C. mexicana itself is untested, with no RCT and no established dose.

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GymnemaGymnema sylvestreModerate

Blood-sugar control is gymnema’s best-evidenced use. A 2021 systematic review/meta-analysis (10 studies, 419 participants) and a 2023 meta-analysis of six RCTs both found significant reductions in fasting blood glucose in type 2 diabetes, and the foundational GS4 water-soluble leaf-extract programme (400 mg/day) cut blood glucose, HbA1c and glycosylated proteins over 18–20 months in both T2DM and insulin-dependent patients 80,81,82,83Reference 80Devangan et al. · 2021Meta-analysisThe effect of Gymnema sylvestre supplementation on glycemic control in type 2 diabetes patients: A systematic review and meta-analysisView study →Reference 81Zamani et al. · 2023Meta-analysisThe effects of Gymnema sylvestre supplementation on lipid profile, glycemic control, blood pressure, and anthropometric indices in adults: A systematic review and meta-analysisView study →Reference 82Baskaran et al. · 1990Clinical trialAntidiabetic effect of a leaf extract from Gymnema sylvestre in non-insulin-dependent diabetes mellitus patients — clinical trialView study →Reference 83Shanmugasundaram et al. · 1990Clinical trialUse of Gymnema sylvestre leaf extract in the control of blood glucose in insulin-dependent diabetes mellitus — clinical trialView study →, with insulin/β-cell stimulation as a plausible mechanism 84Reference 84Al-Romaiyan et al. · 2010Clinical trialA novel Gymnema sylvestre extract stimulates insulin secretion from human islets in vivo and in vitro — clinical trialView study →. Trials are small, largely open-label or low-quality, and use standardised extracts rather than the raw leaf or a 1:2 liquid extract.

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Holy BasilOcimum tenuiflorumModerate

A randomised, placebo-controlled crossover trial in non-insulin-dependent diabetics found holy basil leaf significantly lowered fasting blood glucose (−21 mg/dL, ~17.6%) and postprandial glucose (~7.3%) 89Reference 89Agrawal et al. · 1996RCTRandomised placebo-controlled, single-blind trial of holy basil leaves in patients with non-insulin-dependent diabetes mellitus — randomised controlled trialView study →, set within a wider animal/review body framing tulsi as antidiabetic via insulin-secretion and lipid-handling effects 90Reference 90Kapoor et al. · 2008ReviewOcimum sanctum: a therapeutic role in diabetes and the metabolic syndrome — reviewView study →. The effect is real but modest and rests largely on one small, single-blind, decades-old trial. Tulsi can add to the effect of antidiabetic drugs, but the evidence is too thin to make it a glucose-lowering therapy.

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RehmanniaRehmannia glutinosaModerate

Catalpol lowers blood glucose across many rodent models (2.5–200 mg/kg) via AMPK/PI3K-Akt, PPAR and AGE/RAGE signalling 105,106,107Reference 105Bhattamisra SK et al. · 2021ReviewMolecular and biochemical pathways of catalpol in alleviating diabetes mellitus and its complications — reviewView study →Reference 106Huang WJ et al. · 2010AnimalAntihyperglycemic effect of catalpol in streptozotocin-induced diabetic rats — animal modelView study →Reference 107Bai Y et al. · 2019ReviewCatalpol in diabetes and its complications: pharmacology, pharmacokinetics and safety — reviewView study →, and the root polysaccharide independently reduced hyperglycemia, hyperlipidemia and vascular inflammation in STZ-diabetic mice 108Reference 108Zhou J et al. · 2015AnimalRehmannia glutinosa polysaccharide ameliorates hyperglycemia, hyperlipemia and vascular inflammation in streptozotocin-induced diabetic mice — animal modelView study →.

The only human signals are multi-herb formulas — a 48-week Rehmannia-6 formula slowed eGFR decline in type-2 diabetes with kidney disease 109Reference 109Chan KW et al. · 2023RCTAdd-on Rehmannia-6-based Chinese medicine in type-2 diabetes and CKD — multicenter randomised controlled trialView study → and a Liuwei Dihuang + metformin study reported better glycemic indices 110Reference 110Li N et al. · 2023Clinical trialLiuwei Dihuang (six-drug Rehmannia bolus) as adjunct to metformin in senile type-2 diabetes — clinical studyView study →. No trial has tested rehmannia root, catalpol or the polysaccharide as a single agent in humans.

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SageSalvia officinalisModerate

In hyperlipidaemic type-2 diabetics (n=80), sage leaf extract 500 mg tds for 3 months lowered fasting glucose and HbA1c (and improved lipids) with no adverse effects 113Reference 113Kianbakht et al. · 2013RCTImproved glycemic control and lipid profile in hyperlipidemic type-2 diabetic patients consuming Salvia officinalis L. leaf extract: a randomised placebo-controlled clinical trialView study →; a further trial found it safe and additive to statins in dyslipidaemic diabetics 114Reference 114Kianbakht et al. · 2016RCTSalvia officinalis (sage) leaf extract as add-on to statin therapy in hypercholesterolemic type-2 diabetic patients: a randomised clinical trialView study →. The trials are small, come mostly from one Iranian research group, and used a standardised extract, not tea.

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Stinging NettleUrtica dioicaModerate

The fasting-glucose signal is consistent but HbA1c is inconsistent between analyses, trials are small, short, mostly Iranian, and use non-standardised leaf preparations — durable glycaemic benefit is unproven.

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TeaCamellia sinensisModerate

The evidence is mixed. A 17-RCT meta-analysis found green tea lowered fasting glucose (-0.09 mmol/L) and HbA1c (-0.30%) 126Reference 126Liu et al. · 2013Meta-analysisEffect of green tea on glucose control and insulin sensitivity: a meta-analysis of 17 randomised controlled trialsView study →, but a meta-analysis restricted to type-2 diabetics found no significant effect on glucose, insulin, HbA1c or HOMA-IR 127Reference 127Asbaghi et al. · 2021Meta-analysisEffect of green tea on glycemic control in patients with type 2 diabetes mellitus: a systematic review and meta-analysisView study →; EGCG, tannins and theaflavins improve insulin sensitivity in vitro/animals 128Reference 128Moore et al. · 2009ReviewGreen tea (Camellia sinensis) catechins and vascular function — reviewView study →.

The benefit seen in mixed/healthy populations disappears in the group that matters clinically — established type 2 diabetics — so glycaemic treatment use is not supported.

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AlbizziaAlbizzia lebbeckPreclinical

Albizia lebbeck stem-bark extract protected pancreatic islet-of-Langerhans cells from oxidative damage in streptozotocin-diabetic rats 1Reference 1Saha et al. · 2009AnimalThe analgesic and anti-inflammatory activities of the extract of Albizia lebbeck in animal model — animal modelView study →, consistent with confirmed hypoglycaemic activity of the bark 2Reference 2Meshram et al. · 2015AnimalCentral analgesic activity of the aqueous and ethanolic extracts of the leaves of Albizia lebbeck: role of the GABAergic and serotonergic pathways — animal modelView study →; a related species (A. odoratissima) was anti-diabetic in alloxan-diabetic mice 3Reference 3Patel et al. · 2015AnimalAntihyperglycemic activity of Albizzia lebbeck bark extract in streptozotocin–nicotinamide induced type II diabetes mellitus rats — animal modelView study →. All animal/in-vitro — no human diabetes trial, and part of the rationale leans on a different Albizia species.

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AstragalusAstragalus membranaceusPreclinical

Astragalus polysaccharides, saponins and flavonoids show glucose-lowering and insulin-sensitising activity in preclinical models 11Reference 11Zhang et al. · 2015Systematic reviewBiological active ingredients of traditional Chinese herb Astragalus membranaceus on treatment of diabetes — a systematic reviewView study →, and it features in many Chinese anti-diabetic formulas. But the human trial evidence concentrates on a diabetic complication — nephropathy 12,13Reference 12Li et al. · 2011Meta-analysisMeta-analysis of the clinical value of Astragalus membranaceus in diabetic nephropathy — randomized/controlled trialsView study →Reference 13Lin et al. · 2024Meta-analysisEfficacy of astragalus combined with RAAS blockers in stage III diabetic nephropathy — a systematic review and meta-analysis of randomized controlled trialsView study → — rather than glycaemic control itself; no robust human RCT shows oral astragalus meaningfully lowers HbA1c or fasting glucose as a primary outcome 11Reference 11Zhang et al. · 2015Systematic reviewBiological active ingredients of traditional Chinese herb Astragalus membranaceus on treatment of diabetes — a systematic reviewView study →. The glycaemic claim rests on mechanism and constituents alone.

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BurdockArctium lappaPreclinical

Rodent-only but consistent: burdock root hydro-alcoholic extract lowered glucose and improved lipids in type-2 diabetic mice 23Reference 23Ahangarpour et al. · 2017AnimalAntidiabetic, hypolipidemic and hepatoprotective effects of Arctium lappa root extract in type 2 diabetic mice — animal modelView study →, root polysaccharide corrected diabetic lipid metabolism via the PKC/NF-κB pathway 24Reference 24Wang et al. · 2019AnimalRegulation of lipid metabolism in diabetic rats by Arctium lappa L. polysaccharide through the PKC/NF-κB pathway — rat in vivoView study →, and arctigenin improved insulin resistance through the IRS2/GLUT4 pathway and reshaped gut microbiota in high-fat-diet mice 25,26Reference 25Zhou et al. · 2023AnimalArctigenin mitigates insulin resistance by modulating the IRS2/GLUT4 pathway via TLR4 in type 2 diabetes — animal modelView study →Reference 26Wang et al. · 2024AnimalArctigenin ameliorates high-fat diet-induced metabolic disorders by reshaping gut microbiota — mouse in vivoView study →. There is no human glycaemic trial; every endpoint is animal. The same hypoglycaemic signal means burdock may add to the effect of antidiabetic drugs.

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CashewAnacardium occidentalePreclinical

A hexane leaf extract acted as a hypoglycemic agent in diabetic rats on long-term dosing 30Reference 30Quejada et al. · 2024In vitroUnmasking the antifungal activity of Anacardium occidentale leaf extract against Candida albicans — in vitroView study →, and an ethanol stem-bark extract lowered blood glucose in type-2 diabetic rats only when fed glucose simultaneously — suggesting glucose-dependent insulin stimulation plus possible inhibition of gut glucose absorption 31Reference 31Baptista et al. · 2020AnimalAntioxidant and anti-inflammatory effects of Anacardium occidentale and A. microcarpum extracts on the liver of IL-10 knockout mice — animal studyView study →. All animal/in-vitro; no human trials, and the strongest data are on a related species (A. humile) 32Reference 32Gomes et al. · 2016RCTClinical effect of a mouthwash containing Anacardium occidentale on plaque and gingivitis control — randomised controlled trialView study → rather than A. occidentale itself.

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DamianaTurnera diffusaPreclinical

Hypoglycaemic activity recurs but inconsistently: teuhetenone A isolated from T. diffusa gave an acute hypoglycaemic/antidiabetic effect in a rodent model 46Reference 46Parra-Naranjo et al. · 2017Acute hypoglycemic and antidiabetic effect of teuhetenone A isolated from Turnera diffusa — animal studyView study →, and in a type-2 diabetes rat model leaf extract (100–200 mg/kg, 28 d) improved testicular steroidogenesis mainly via antioxidant/anti-inflammatory (NF-κB↓) action rather than direct glucose lowering 47Reference 47Kumar et al. · 2023AnimalOral Turnera diffusa extract ameliorates steroidogenesis and spermatogenesis impairment in the testes of type-2 diabetic rats — animal studyView study →. Older literature says the active fraction is water-soluble (an alcoholic tincture may under-deliver); results are dose-/fraction-dependent, sometimes null on blood glucose itself, and there is no human glycaemic data.

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DandelionTaraxacum officinalePreclinical

Constituents isolated from dandelion (novel butyrolactones, phenolics) inhibit α-glucosidase in vitro, an action that would blunt post-meal glucose absorption 48Reference 48Choi J et al. · 2018In vitroChemical constituents from Taraxacum officinale and their α-glucosidase inhibitory activities — [in vitro]View study →; chicoric/chlorogenic acid and the prebiotic fructan inulin are also invoked in a type-2 diabetes review 49Reference 49Wirngo FE et al. · 2016ReviewThe Physiological Effects of Dandelion (Taraxacum Officinale) in Type 2 Diabetes — [review]View study →. The one animal efficacy study combined dandelion with Momordica charantia (bitter melon) — a potent hypoglycaemic in its own right — so dandelion’s independent contribution is unclear 50Reference 50Perumal N et al. · 2022AnimalSynergistic antidiabetic activity of Taraxacum officinale (L.) Weber ex F.H.Wigg and Momordica charantia L. polyherbal combination — [in vivo animal]View study →. No monotherapy animal or human glycaemic data.

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Fish MintHouttuynia cordataPreclinical

Several independent streptozotocin-diabetic-rat studies converge: standardised, ethanolic and fermented extracts lowered fasting glucose and improved insulin/lipids, attributed to β-cell protection, GLUT-4 up-regulation and antioxidant (Nrf2/HO-1) activity 91,92,93Reference 91Kumar et al. · 2014AnimalAntihyperglycemic activity of Houttuynia cordata Thunb. in streptozotocin-induced diabetic rats — animal modelView study →Reference 92Rahman et al. · 2024AnimalImpacts of Plu kaow (Houttuynia cordata) ethanolic extract on diabetes and dyslipidemia in STZ-induced diabetic rats — animal modelView study →Reference 93Sakuludomkan et al. · 2021AnimalEffects of fermented Houttuynia cordata on diabetic rats and on insulin resistance in 3T3-L1 adipocytes — animal modelView study →. Reproducible across labs but confined to rodents in chemically-induced diabetes; no human glucose or HbA1c data, and doses were high relative to culinary intake.

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Goat’s RueGalega officinalisPreclinical

Goat’s rue is the ancestral antidiabetic herb — its guanidine alkaloid galegine led directly to the biguanides and metformin 65Reference 65Hadden · 2005ReviewGoat’s rue — French lilac — Italian fitch — Spanish sainfoin: Galega officinalis and metformin: the Edinburgh connection — historical reviewView study → — and the mechanism is well-resolved at the molecule level: galegine activates AMPK and drives glucose uptake in adipocytes/myotubes 66Reference 66Mooney et al. · 2008In vitroMechanisms underlying the metabolic actions of galegine that contribute to weight loss in mice — animal model / in vitroView study →, acts via imidazoline I2 receptors 67Reference 67Lui et al. · 2010In vitroActivation of imidazoline I2B receptors is linked with AMP kinase pathway to increase glucose uptake in cultured C2C12 cells — in vitroView study →, and inhibits mitochondrial respiratory-chain complex IV to suppress gluconeogenesis 68Reference 68LaMoia et al. · 2022In vitroMetformin, phenformin, and galegine inhibit complex IV activity and reduce glycerol-derived gluconeogenesis — in vitro / in vivoView study →; the herb’s own extracts inhibit α-amylase, α-glucosidase, maltase and sucrase in vitro 69Reference 69Sukhtezari et al. · 2024In vitroIn vitro antidiabetic and antioxidant activities of Galega officinalis extracts — in vitroView study →. But there is no human trial of goat’s rue for any glycaemic endpoint — the strongest data are for isolated galegine or metformin, not standardised herb — and galegine content varies several-fold by plant part and growth stage 70Reference 70Oldham et al. · 2011Galegine content in goatsrue (Galega officinalis) varies by plant part and phenological growth stage — analytical / toxicologyView study →, so extract results don’t transfer to a tea, tincture or powder of unknown alkaloid load.

Full monograph
GraviolaAnnona muricataPreclinical

Glucose lowering is graviola’s most consistently reproduced animal effect: leaf extracts improved glycaemic control in alloxan–nicotinamide diabetic rats 71Reference 71Zubaidi et al. · 2025AnimalDeciphering the mechanism of Annona muricata leaf extract in alloxan–nicotinamide-induced diabetic rats — animal modelView study →, reduced hyperglycaemia and hepatic damage in STZ-diabetic rats 72Reference 72Son et al. · 2021AnimalAmeliorative effect of Annona muricata (Graviola) extract on hyperglycaemia-induced hepatic damage in STZ diabetic rats — animal modelView study →, prevented high-fat-diet metabolic disorder 73Reference 73Sasso et al. · 2019AnimalUse of an extract of Annona muricata to prevent high-fat-diet-induced metabolic disorders — animal modelView study → and partially restored pancreatic β-cells 74Reference 74Adeyemi et al. · 2010AnimalHistomorphological and morphometric studies of the pancreatic islet cells of diabetic rats treated with Annona muricata — animal modelView study →. The signal is robust across preparations and induction models, but human evidence is limited to a small adjunctive study and ethnobotanical data — no adequately powered trial, no standardised dose. Graviola can add to the glucose-lowering effect of diabetes drugs.

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Lion’s ManeHericium erinaceusPreclinical

A single 2013 study in streptozotocin-induced diabetic rats found aqueous fruiting-body extract (100–200 mg/kg, 28 days) lowered blood glucose and improved insulin and lipid profiles 94Reference 94Liang et al. · 2013AnimalAntihyperglycemic and antihyperlipidemic activities of aqueous extract of Hericium erinaceus in experimental diabetic rats — animal modelView study →. One rodent model, animal-only, no human confirmation.

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SarsaparillaSmilax spp.Preclinical

S. glabra rhizome extracts lowered blood glucose in normal and diabetic mice 115Reference 115Fukunaga T et al. · 1997AnimalHypoglycemic effect of the rhizomes of Smilax glabra in normal and diabetic mice — animal modelView study →, and an ethyl-acetate fraction with α-glucosidase/α-amylase inhibition reduced glucose and insulin resistance in a type-2 model 116Reference 116Nguyen PTM et al. · 2020AnimalHypoglycemic activity of the ethyl acetate extract from Smilax glabra Roxb in mice — animal modelView study →. Heterogeneous species and fractions, rodent-only, no human glycaemic data.

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SumaPfaffia paniculataPreclinical

Suma appears on lists of Brazilian “hypoglycemiant” plants and one study characterised its trace-element profile 125Reference 125Zucchi et al. · 2005In vitroCharacterization of hypoglycemiant plants by total reflection X-ray fluorescence spectrometry — in vitro/analytical studyView study →, but no study — animal or human — tests it against a glucose endpoint. The rationale is purely constituent-level (phytosterols, ecdysteroids).

Full monograph
YarrowAchillea millefoliumPreclinical

Rodent-only support: a hydroalcoholic extract protected pancreatic β-cells in diabetic rats by down-regulating IL-1β and iNOS 132Reference 132Zolghadri Y et al. · 2014AnimalAchillea millefolium L. hydro-alcoholic extract protects pancreatic cells by down regulating IL-1β and iNOS gene expression in diabetic rats — [rat in vivo]View study →, and in streptozotocin-diabetic rats the extract lowered blood glucose, triglycerides and LDL while raising HDL, comparable to metformin on several endpoints 133Reference 133Rezaei S et al. · 2020AnimalHydroalcoholic extract of Achillea millefolium improved blood glucose, liver enzymes and lipid profile compared to metformin in streptozotocin-induced diabetic rats — [rat in vivo]View study →. No controlled human data for yarrow alone; the one registered human trial is a multi-herb “antidiabetic tea” that cannot isolate yarrow’s contribution.

Full monograph
SaffronCrocus sativusTraditional only

A 2024 meta-analysis found saffron/crocin produced modest reductions in fasting blood glucose and metabolic parameters in T2DM 111Reference 111Amatto PPG et al. · 2024Meta-analysisEffect of Crocus sativus L. (saffron) and crocin in the treatment of patients with type-2 diabetes mellitus: a systematic review and meta-analysisView study →, and a prediabetes RCT (15 mg/day) lowered FBS and HbA1c and raised antioxidant status over 8 weeks 112Reference 112Karimi-Nazari E et al. · 2019RCTEffect of saffron (Crocus sativus L.) on lipid profile, glycemic indices and antioxidant status among overweight/obese prediabetic individuals: a double-blinded, randomised controlled trialView study →. The effects are small and heterogeneous, which makes saffron an adjunct at best, not a replacement for standard glycaemic management.

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Devils clubOplopanax horridusNo benefit shown

Blood-sugar balance is devil’s club’s most famous traditional use (“Alaskan ginseng”), and the direction of the human evidence is negative: the one human study, a 1990 pilot monitoring blood glucose in an insulin-dependent diabetic, a newly diagnosed type-2 diabetic and two healthy adults drinking devil’s club tea, found no hypoglycaemic effect 51Reference 51Thommasen HV et al. · 1990Effect of Devil’s Club Tea on Blood Glucose Levels in Diabetes Mellitus — [human pilot study]View study →. Positive claims trace only to early-20th-century animal reports (hypoglycaemia in rabbits) catalogued in ethnopharmacological reviews 52,53,54Reference 52Wu K et al. · 2018ReviewOplopanax horridus: Phytochemistry and Pharmacological Diversity and Structure-Activity Relationship on Anticancer Effects — [review]View study →Reference 53Calway T et al. · 2012ReviewChemical and pharmacological studies of Oplopanax horridus, a North American botanical — [review]View study →Reference 54Smith GW · 1983ReviewArctic pharmacognosia IIView study →.

Full monograph

Supplementation

Supplementation

Supplements, nutrients and compounds used for diabetes.

BerberineAlkaloid (isoquinoline) CagrilintideLong-acting amylin analogue (dual amylin/calcitonin receptor agonist) MagnesiumMineral RetatrutideGLP-1/GIP/glucagon triple receptor agonist (investigational) SurvodutideGlucagon/GLP-1 receptor dual agonist (investigational)

References

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  49. Wirngo FE, Lambert MN, Jeppesen PB (2016). The Physiological Effects of Dandelion (Taraxacum Officinale) in Type 2 Diabetes — [review]. Rev Diabet Stud. https://pubmed.ncbi.nlm.nih.gov/28012278/
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