Natural remedies for blood sugar
Direct answer
Nothing here is better than moderate evidence: white mulberry leaf extract lowered the blood sugar rise after a meal in small single-meal trials (rated 3). These are at best small add-ons and never a replacement for diabetes medication or your care plan. The caution that matters most is that several of them may add to diabetes drugs, so ask your prescriber before adding any of them.
The mulberry trials were mostly in healthy people and linked to the manufacturer. Over weeks, every ingredient rates 2 (limited) or lower for fasting glucose or HbA1c, cinnamon included.
The Cochrane review of cinnamon found no HbA1c difference, and the common cassia cinnamon carries a coumarin liver caution.
Compare the options
Of the 12 remedies for blood sugar we have rated, 4 have Moderate or Strong evidence for this use (none Strong). See our evidence report.
Click a column heading to sort.
| Rated for | Typical form & use | Main caution | |||
|---|---|---|---|---|---|
| Berberine Plant alkaloid (barberry, goldenseal) | Moderate | Blood sugar in type 2 diabetes | Berberine, 900–1,500 mg daily, split | Many drug interactions; never in pregnancy or for babies | 4+ weeks |
| Black seed oil Nigella sativa (seed oil) | Moderate | Blood sugar in type 2 diabetes | Seed oil capsules, 1–3 g daily | Adds to diabetes and blood pressure medicines | 4+ weeks |
| Inositol Myo- and D-chiro-inositol (cyclitol) | Moderate | Preventing gestational diabetes | Myo-inositol, 2 g twice daily | Pregnancy: ask your midwife or doctor before starting | 4+ weeks |
| White mulberry leaf Morus alba (leaf) | Moderate | Blood sugar after a carbohydrate meal | Leaf extract, 200–250 mg before a meal | Little long-term safety data; ask first if on diabetes drugs | Same night |
| Cinnamon Cinnamomum cassia / verum (bark, oil) | Limited | Blood sugar in type 2 diabetes | Powder or capsule, 1.5–2 g daily | Cassia coumarin can harm the liver at high intake | 4+ weeks |
| Ginseng Panax ginseng (root) | Limited | Fasting blood sugar | Panax ginseng and related species | May lower blood sugar and disturb sleep | 4+ weeks |
| Holy basil (tulsi) Ocimum tenuiflorum (leaf) | Limited | Blood sugar in type 2 diabetes | Leaf powder, about 2–3 g daily | Long-term safety unstudied; check with diabetes drugs | 4+ weeks |
| Moringa Moringa oleifera (leaf) | Limited | Blood sugar in prediabetes | Leaf powder or capsules | Diabetes medicine: effects may add up, ask first | About a week |
| Psyllium Plantago ovata (seed husk) | Limited | Blood sugar in type 2 diabetes | Husk powder, about 10 g a day in water | With diabetes, use only under medical supervision | 4+ weeks |
| Spirulina Arthrospira platensis (blue-green algae) | Limited | Fasting blood sugar | Tablet, capsule or powder, 1–10 g daily | Product quality varies; may aggravate autoimmune disease | 4+ weeks |
| Yerba mate Ilex paraguariensis (leaf) | Limited | Blood sugar in prediabetes | Tea or capsules, about 3 g leaf a day | Contains caffeine; drink below 65 °C | 4+ weeks |
| Rooibos Aspalathus linearis (leaf, as tea) | Traditional | Blood sugar | Tea; no dose tested for blood sugar | Rare liver injury case reports | 4+ weeks |
- Rated for
- Blood sugar in type 2 diabetes
- Form
- Berberine, 900–1,500 mg daily, split
- Onset
- 4+ weeks
- Rated for
- Blood sugar in type 2 diabetes
- Form
- Seed oil capsules, 1–3 g daily
- Onset
- 4+ weeks
- Rated for
- Preventing gestational diabetes
- Form
- Myo-inositol, 2 g twice daily
- Onset
- 4+ weeks
- Rated for
- Blood sugar after a carbohydrate meal
- Form
- Leaf extract, 200–250 mg before a meal
- Onset
- Same night
- Rated for
- Blood sugar in type 2 diabetes
- Form
- Powder or capsule, 1.5–2 g daily
- Onset
- 4+ weeks
- Rated for
- Fasting blood sugar
- Form
- Panax ginseng and related species
- Onset
- 4+ weeks
- Rated for
- Blood sugar in type 2 diabetes
- Form
- Leaf powder, about 2–3 g daily
- Onset
- 4+ weeks
- Rated for
- Blood sugar in prediabetes
- Form
- Leaf powder or capsules
- Onset
- About a week
- Rated for
- Blood sugar in type 2 diabetes
- Form
- Husk powder, about 10 g a day in water
- Onset
- 4+ weeks
- Rated for
- Fasting blood sugar
- Form
- Tablet, capsule or powder, 1–10 g daily
- Onset
- 4+ weeks
- Rated for
- Blood sugar in prediabetes
- Form
- Tea or capsules, about 3 g leaf a day
- Onset
- 4+ weeks
- Rated for
- Blood sugar
- Form
- Tea; no dose tested for blood sugar
- Onset
- 4+ weeks
Quick picks
Rated 3 for the blood sugar rise after a carbohydrate meal: the glucose rise fell by 30 to 42% in small single-meal trials in healthy adults. Over weeks in people with raised glucose the rating is 2, and a pilot in type 2 diabetes found no HbA1c difference from placebo.
Gentlest optionPsylliumRated 2 for blood sugar in type 2 diabetes: a 2015 meta-analysis reported HbA1c 0.97 percentage points lower, but its authors worked for a psyllium manufacturer. It is a fibre with a strong record for constipation and LDL cholesterol, and it must be taken with plenty of fluid.
Traditional favouriteHoly basil (tulsi)Rated 2 for type 2 diabetes: a 2017 review found ten small trials, mostly 2 to 13 weeks, generally reporting lower glucose, but only about a third of the studies in the review were high quality. It has a long Ayurvedic history and nothing has been studied beyond 13 weeks.
Key facts about blood sugar
- About 1 in 8 Americans has diabetes, an estimated 40.1 million people in 2023, and 27.6% of US adults with it (about 11.0 million) have not been diagnosed.9
- More than 2 in 5 US adults have prediabetes (an estimated 115.2 million), where blood sugar is higher than normal but not yet type 2 diabetes. Lifestyle changes can cut the risk of type 2 diabetes in half.9,10
- Almost 6 million people in the UK are estimated to have diabetes, including almost 1.3 million with type 2 diabetes who have not yet been diagnosed. Over 12 million UK adults have diabetes or prediabetes.11
- Every week in the UK, diabetes leads to 184 amputations, more than 1,010 strokes and 700 heart attacks. Its total cost to the NHS is an estimated £10.7 billion, 60% of it spent on complications.11
- Worldwide, the number of people living with diabetes rose from 200 million in 1990 to 830 million in 2022, and more than half (59%) of adults aged 30 and over with diabetes were not taking medication for it.12
- In the UK, type 2 diabetes is more likely if you are white and over 40, or over 25 and from a South Asian, Chinese, Black African or Black Caribbean background, or a parent or sibling has it. Not everyone gets symptoms.13
- In 2009–2020, 61.72% of US adults with diabetes used dietary supplements, most often multivitamins, minerals, vitamin D and calcium, and only 44.58% did so on medical advice.14
Talk to a doctor first if…
Who should avoid
- Pregnancy and breastfeeding: mulberry, holy basil and ginseng are on the avoid list, because no safety data exist or the EU regulator advises against it.
- Difficulty swallowing or a bowel blockage: do not take psyllium, and do not take it without plenty of fluid.
- Kidney problems: be cautious with mulberry, since one trial saw a 15% rise in serum creatinine.
- Liver disease or large daily amounts: cassia cinnamon is best avoided, because its coumarin can harm the liver (about 2 g a day of cassia reaches the limit for a 60 kg adult).
- Yerba mate: it contains caffeine and should be drunk below 65 °C.
Known interactions
- Diabetes medication and psyllium: your treatment may need adjusting, and psyllium should only be used under medical supervision (rated 2, caution).
- Holy basil and glibenclamide: added to glibenclamide, holy basil lowered HbA1c and glucose further than the drug alone in a 13-week trial (lower-rated, severity 1 or unrated).
- Ginseng and mulberry: ginseng may lower blood sugar, and mulberry effects on glucose are described as adding up (lower-rated, severity 1 or unrated).
- Cinnamon and glucose-lowering medicines: cinnamon could in theory add to them (severity 1; no case of harm was reported in the sources we read).
- Psyllium and thyroid hormones or coumarin anticoagulants: psyllium can delay their absorption, so keep doses apart and ask a pharmacist.
- Ginseng and warfarin: ginseng weakened warfarin in one small trial.
- Cinnamon and statins: one case report links cinnamon supplements taken with a statin to acute hepatitis.
Before you reach for an ingredient
Diet, activity and weight changes have far stronger evidence than any ingredient here; talk to your GP or diabetes team before changing your plan.
- Structured lifestyle programmes for people with prediabetes: a 2025 meta-analysis of 31 randomised trials found face-to-face lifestyle interventions cut the risk of developing type 2 diabetes by 46% (RR 0.54, 95% CI 0.47 to 0.63) compared with usual care; digital-only programmes had not been shown to work as well (RR 0.88, 95% CI 0.77 to 1.01).1
- Combined aerobic and resistance exercise: a 2024 meta-analysis of 20 studies (1,192 people with type 2 diabetes and overweight or obesity) reported improvements in HbA1c, blood pressure and inflammation markers, although the authors describe the risk of bias as uncertain and the evidence quality as poor.2
Questions people ask
Can herbs lower blood sugar?
A few, by small amounts. White mulberry leaf lowers the rise after a meal in short trials (rated 3), and psyllium fibre may lower HbA1c in people with type 2 diabetes (rated 2), but most trials are small, short or manufacturer-linked.
Cinnamon is widely taken, but the Cochrane review found the fasting glucose effect inconclusive and no HbA1c difference, and a 2025 meta-analysis that did find lower glucose was highly inconsistent (rated 2). They are not a substitute for diabetes medication.
Can I take these with metformin or other diabetes tablets?
Ask your prescriber or pharmacist first. Psyllium may mean your treatment needs adjusting, and holy basil added to glibenclamide lowered glucose further in one trial, so effects may add together. We found no trial of low blood sugar (hypoglycaemia) with these herbs, so the size of the risk is unknown.
Does ginseng help with blood sugar?
Slightly at best. A meta-analysis of 16 trials found fasting glucose fell by 0.31 mmol/L, but HbA1c and insulin resistance did not change overall and most trials lasted under 12 weeks (rated 2). NCCIH calls the evidence in diabetes inconclusive.
Is rooibos tea good for diabetes?
There is no evidence it is. We rate rooibos 1 (traditional) for blood sugar, because no human trial we opened tested it in people with diabetes. It is a caffeine-free tea that is widely drunk, but there are rare case reports of liver injury.
Sources (14)
- Meta-analysis Wang Y, Chai X, Wang Y, Yin X, Huang X, Gong Q, Zhang J, Shao R, Li G. Effectiveness of Different Intervention Modes in Lifestyle Intervention for the Prevention of Type 2 Diabetes and the Reversion to Normoglycemia in Adults With Prediabetes: Systematic Review and Meta-Analysis of Randomized Controlled Trials. J Med Internet Res. 2025.
- Meta-analysis Al-Mhanna SB, Batrakoulis A, Wan Ghazali WS, et al. Effects of combined aerobic and resistance training on glycemic control, blood pressure, inflammation, cardiorespiratory fitness and quality of life in patients with type 2 diabetes and overweight/obesity: a systematic review and meta-analysis. PeerJ. 2024.
- Meta-analysis Cui W, Luo K, Xiao Q, et al. Effect of mulberry leaf or mulberry leaf extract on glycemic traits: a systematic review and meta-analysis. Food Funct. 2023.
- Randomised trial Thondre PS, Lightowler H, Ahlstrom L, Gallagher A. Mulberry leaf extract improves glycaemic response and insulaemic response to sucrose in healthy subjects: results of a randomized, double blind, placebo-controlled study. Nutr Metab (Lond). 2021.
- Meta-analysis Gibb RD, McRorie JW Jr, Russell DA, Hasselblad V, D'Alessio DA. Psyllium 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. Am J Clin Nutr. 2015.
- Meta-analysis Shishtar E, Sievenpiper JL, Djedovic V, et al. The effect of ginseng (the genus panax) on glycemic control: a systematic review and meta-analysis of randomized controlled clinical trials. PLoS One. 2014.
- Systematic review Jamshidi N, Cohen MM. The Clinical Efficacy and Safety of Tulsi in Humans: A Systematic Review of the Literature. Evid Based Complement Alternat Med. 2017.
- Meta-analysis Li D, Yue L, Peng X, et al. Yerba Maté and its impact on glycemic control and metabolic health: a systematic review and meta-analysis. Front Endocrinol (Lausanne). 2025.
- Government statistics Centers for Disease Control and Prevention. National Diabetes Statistics Report. cdc.gov (updated 16 September 2026).
- Health agency guidance Centers for Disease Control and Prevention. Prediabetes – Your Chance to Prevent Type 2 Diabetes. cdc.gov. 2024.
- Charity statistics Diabetes UK. How many people in the UK have diabetes? diabetes.org.uk. 2025.
- Health agency fact sheet World Health Organization. Diabetes (fact sheet). 2024.
- Health service guidance NHS. Symptoms of type 2 diabetes and how it’s diagnosed. nhs.uk (page last reviewed 10 February 2025).
- Population survey analysis Jiang Y, Chen X, Cai Z, Yao Y, et al. Trends and Motivations in Dietary Supplement Use Among People with Diabetes: A Population-Based Analysis Using National Health and Nutrition Examination Survey Data from the 2009–2020 Period. Nutrients. 2024.
Reviewed by Healthy and Herbal editors · 10 October 2026 · Next review April 2027
Reader notes
Experiences and questions from readers, read by an editor before they appear. They are personal accounts, not evidence, and are not medical advice.