Ginger and blood sugar: small drops, all from capsules

In adults with type 2 diabetes, ginger supplements lowered fasting blood sugar by about 16 mg/dL (95% CI -25.75 to -6.80) and HbA1c by 0.41 percentage points, according to a 2026 meta-analysis of 13 placebo-controlled trials. Its authors call those effects of limited clinical importance, and the trials disagreed sharply with each other (I2 86 to 92 percent). A second 2026 meta-analysis, of 13 trials with 837 people, found almost the same drop of 16.22 mg/dL (95% CI -25.49 to -6.95) and HbA1c down 0.49 points, with heterogeneity up to 98 percent. The two probably share many of the same trials. Every trial gave ginger as a supplement, mostly capsules of powdered root, and none tested it as a replacement for diabetes medicine. We found no trial of ginger eaten as food and none of candied or crystallized ginger. An older meta-analysis of 8 trials with 454 people with type 2 diabetes, taking 1.6 to 4 g a day, found no significant change in fasting blood sugar (P = 0.16). It compared each arm before and after instead of ginger against placebo, so the answer stays unclear even though the larger pools lean toward a drop. A 2026 umbrella review of 36 meta-analyses adds its own warning: not one of them met all the AMSTAR 2 critical quality criteria.

How much is actually in it

• The UK food table gives fresh ginger 1.7 g of sugars and 44 calories per 3.5 oz (100 g), while dried ground ginger has 19.8 g of sugars and 284 calories because the water is gone. — CoFID 2021 codes 13-890 Ginger, fresh and 13-832 Ginger, ground Evidence E source
  Per 100 g: fresh ginger sugars 1.7 g, carbohydrate 8.1 g, 44 calories, water 78.9 g; ground ginger sugars 19.8 g, carbohydrate 60.0 g, 284 calories, water 9.4 g

What a real portion looks like

• In the US dietary survey a cup of ginger tea is counted as 240 g and an unspecified serving of pickled ginger as 30 g. — USDA FNDDS foods Tea, ginger and Ginger root, pickled Evidence E source
  Ginger tea: 1 cup 240 g, 1 medium 480 g; pickled ginger root: quantity not specified 30 g, 1 cup 240 g

What it does to your health

• A 2026 meta-analysis of 13 RCTs in type 2 diabetes found ginger lowered fasting blood sugar by about 16 mg/dL and HbA1c by 0.41 points, effects the authors call of limited clinical importance. — adults with type 2 diabetes in 13 placebo-controlled RCTs, searched to July 2025 (n = 13 trials) Evidence A source
  FBS MD -16.27 mg/dL (95% CI -25.75 to -6.80); HbA1c MD -0.41% (-0.63 to -0.20); high heterogeneity
• A 2022 meta-analysis of RCTs in type 2 diabetes pooled a fasting glucose drop of about 19 mg/dL and an HbA1c drop of 0.57 points with ginger supplements. — adults with type 2 diabetes, 10 RCTs searched to September 2021 (n = 10 trials) Evidence A source
  FBS WMD -18.81 (95% CI -28.70 to -8.92), I2 77.4%; HbA1c WMD -0.57 (-0.93 to -0.20), I2 88.6%
• A 2026 review pooling 41 RCTs found ginger supplements lowered fasting blood sugar by about 13 mg/dL and HbA1c by 0.68 points. — 41 RCTs of ginger supplementation in adults, searched to January 2025 (n = 41 trials) Evidence A source
  FBS WMD -12.79 mg/dL; HbA1c WMD -0.68% (95% CI -1.00 to -0.36); HOMA-IR -0.51 (-0.68 to -0.33)
• In an 8-week RCT in 88 people with diabetes, 3 g of ginger powder a day cut fasting blood sugar by 10.5% while it rose 21% on placebo. — 88 adults with diabetes, three 1 g ginger capsules daily or placebo for 8 weeks (n = 88) Evidence B source
  FBS -10.5% (p = 0.003) with ginger vs +21% with placebo (p = 0.01)
• In a 12-week RCT in 70 people with type 2 diabetes, 1600 mg ginger a day lowered fasting glucose, HbA1c and insulin compared with a wheat flour placebo. — 70 adults with type 2 diabetes, 1600 mg ginger or placebo daily for 12 weeks (n = 70) Evidence B source
  Significant reductions in fasting plasma glucose, HbA1c, insulin and HOMA versus placebo (p < 0.05); sizes not in abstract
• A 2026 meta-analysis of 13 RCTs with 837 people with type 2 diabetes found ginger lowered fasting blood sugar by about 16 mg/dL and HbA1c by 0.49 points, more so at doses under 2000 mg a day. — 837 adults with type 2 diabetes in 13 placebo-controlled RCTs, searched to 12 November 2025 (n = 837) Evidence A source
  FBS WMD -16.22 mg/dL (95% CI -25.49 to -6.95), I2 85.67%; HbA1c WMD -0.49% (-0.86 to -0.12), I2 98.14%; larger effect below 2000 mg/day, in men, under 54 years and with baseline HbA1c above 8%

Safety, limits and interactions

• A systematic review of 149 reports on warfarin names ginger among foods and herbs that raise bleeding risk with the drug. — 149 articles on 78 herbs, foods and supplements taken with warfarin (n = 149 articles) Evidence C source
  Ginger listed with increased bleeding risk; no size given
• An AHRQ review found that 3.6 g of ginger a day for a week did not change warfarin exposure in 12 healthy men and graded the evidence on INR as insufficient. — 12 healthy men, single 25 mg warfarin dose with or without 7 days of ginger 3.6 g/day (n = 12) Evidence B source
  No change in warfarin AUC, Cmax or half-life; only time to peak shortened; INR evidence insufficient

Who this works differently for

• In overweight and obese adults, a meta-analysis of 14 RCTs (473 people) found ginger lowered fasting glucose (SMD -0.68) and insulin resistance (HOMA-IR). — 473 overweight or obese adults in 14 RCTs, searched to November 2017 (n = 473) Evidence A source
  Fasting glucose SMD -0.68 (95% CI -1.23 to -0.05); HOMA-IR SMD -1.67 (-2.86 to -0.48)
• An umbrella review of 18 systematic reviews found ginger supplements of 450 to 1950 mg a day reduced nausea in pregnancy more than placebo without raising miscarriage or side effects. — 18 systematic reviews of ginger for nausea and vomiting of pregnancy, to December 2024 (n = 18 reviews) Evidence A source
  Lower severity and frequency of nausea and vomiting vs placebo; no rise in spontaneous abortion, heartburn or drowsiness

What is still unknown

• An earlier meta-analysis of 8 RCTs with 454 people with type 2 diabetes taking 1.6 to 4 g ginger a day found no significant change in fasting blood sugar. — 454 adults with type 2 diabetes in 8 randomized trials, ginger 1600-4000 mg daily (n = 454) Evidence A source
  FBS WMD 1.38 (95% CI -0.53 to 3.30), P = .16
• A 2026 umbrella review of 36 meta-analyses found ginger lowered fasting blood sugar and HbA1c in most of them, but no review met all AMSTAR 2 critical quality criteria. — 36 systematic reviews and meta-analyses, 296 trials, 43,570 participants, searched to January 2025 (n = 36 reviews) Evidence A source
  FBS reported WMD range -0.68 to -18.81 mg/dL across 10 meta-analyses; HbA1c -0.27 to -1.66%; certainty moderate to low; 18 reviews moderate, 15 low, 3 critically low quality

The bottom line

The sugar in ginger itself is small at the amounts people use. The UK food table gives fresh ginger 1.7 g of sugars and 44 calories per 3.5 oz (100 g). Ground ginger has 19.8 g of sugars and 284 calories per 3.5 oz (100 g) because the water is gone, and a teaspoon of it weighs a few grams. The US dietary survey counts a cup of ginger tea as 240 g and an unspecified serving of pickled ginger as 30 g. We found no data here on sugar added to candied, crystallized or pickled ginger, so the label is the only guide. Other pools give similar sizes. Ten trials in type 2 diabetes pooled in 2022 came to about 19 mg/dL (95% CI -28.70 to -8.92). Across 41 trials in mixed adult groups, a 2026 review found about 13 mg/dL and HbA1c down 0.68 points, and its abstract gives only one end of the fasting glucose interval. The 837-person analysis saw bigger drops below 2000 mg a day, in men, in people under 54 and when HbA1c started above 8 percent. Those subgroup splits are exploratory, and heterogeneity that high makes them a weak guide to dose. In overweight and obese adults, a meta-analysis of 14 trials with 473 people found ginger lowered fasting glucose by a standardized difference of -0.68 (95% CI -1.23 to -0.05), a unit that does not convert cleanly into mg/dL. Two single trials point the same way. In 88 people with diabetes, 3 g of ginger powder a day for 8 weeks cut fasting blood sugar by 10.5 percent while it rose 21 percent on placebo, a placebo rise the trial leaves unexplained. In 70 people with type 2 diabetes, 1600 mg a day for 12 weeks lowered fasting glucose and HbA1c against a wheat flour placebo, and the abstract gives no sizes. Who should be careful. A systematic review of warfarin interactions lists ginger among the foods and herbs linked to a higher risk of bleeding, and most of what it gathered were case reports. In the one controlled trial AHRQ summarized, ginger did not change how much warfarin reached the blood, and AHRQ graded the evidence on INR as insufficient. Anyone on warfarin who plans to take ginger capsules should raise it with whoever checks their INR. We found no study of ginger taken alongside diabetes medicines, so whether the two add up is an open question, and we found no upper limit set for ginger supplements. The diabetes trials here used 1.6 to 4 g a day. In pregnancy, an umbrella review of 18 systematic reviews found ginger supplements of 450 to 1950 mg a day eased nausea and vomiting more than placebo, with no rise in miscarriage, heartburn or drowsiness. Most of the reviews it gathered were of low or critically low quality.

Sources

1. gsu8-11 · CoFID dataset
   CoFID 2021 13-890 Ginger, fresh: Total sugars 1.7 g, Carbohydrate 8.1 g, Energy 44 kcal, Water 78.9 g per 100 g; 13-832 Ginger, ground: Total sugars 19.8 g, Carbohydrate 60.0 g, Energy 284 kcal, Water 9.4 g per 100 g
   CoFID 2021, Public Health England, codes 13-890 and 13-832 · checked 2026-09-28
2. gsu8-12 · food portion dataset
   Tea, ginger | FNDDS code 92306850 | fdc_id 2710507 | 1 cup 10205 = 240 g | 1 medium 61238 = 480 g; Ginger root, pickled | FNDDS code 75503085 | fdc_id 2710082 | Quantity not specified 90000 = 30 g | 1 cup 10205 = 240 g
   USDA FNDDS, Tea, ginger (92306850, fdc_id 2710507); Ginger root, pickled (75503085, fdc_id 2710082) · checked 2026-09-28
3. gsu8-01 · meta-analysis
   Ginger supplementation was associated with a statistically significant reduction in fasting blood sugar (FBS) (MD -16.27 mg/dl, 95% CI (-25.75, -6.80), I2 = 86.39%), hemoglobin A1c (HbA1c) (MD -0.41%, 95% CI (-0.63, -0.20), I2 = 92.09%) systolic blood pressure (MD -1.62, 95% CI (-3.01, -0.24), I2 = 6.09%), and triglyceride level (MD -17.10 mg/dL, 95% CI (-31.13, -3.07), I2 = 81.61%); however, the magnitude of these effects was of limited clinical importance.
   Syst Rev, 2026 · checked 2026-09-28
4. gsu8-02 · meta-analysis
   Our pooled meta-analysis indicated a significant reduction in FBS following ginger supplementation by polling 8 effect sizes [weighted mean difference (WMD): - 18.81; 95% CI: - 28.70, - 8.92), I2 = 77.4%] and in HbA1C through 7 effect sizes (WMD: -0.57; 95% CI: -0.93, -0.20, I2 =88.6%).
   Complement Ther Med, 2022 · checked 2026-09-28
5. gsu8-04 · meta-analysis
   Forty-one RCTs were included. Ginger supplementation was effective in improving FBS (WMD = -12.79 mg/dL; 95% CI = -18.57), insulin (WMD = -1.33 µIU/ml; 95% CI = -1.94, -0.71), HOMA-IR (WMD = -0.51; 95% CI = -0.68, -0.33), HbA1c (WMD = -0.68%; 95% CI = -1.00, -0.36)
   J Diet Suppl, 2026 · checked 2026-09-28
6. gsu8-06 · randomized trial
   This is a randomized, double-blind, placebo-controlled trial in which 88 participants affected by diabetes were randomly assigned into ginger (GG) and placebo (PG) groups...FBS mean showed a decrease of 10.5% (p=0.003) in the GG whereas the mean had an increase of 21% in the PG (p=0.01).
   Complement Ther Med, 2014 · checked 2026-09-28
7. gsu8-07 · randomized trial
   They consumed 1600 mg ginger versus 1600 mg wheat flour placebo daily for 12 weeks...Ginger reduced fasting plasma glucose, HbA1C, insulin, HOMA, triglyceride, total cholesterol, CRP and PGE₂ significantly compared with placebo group (p < 0.05).
   Int J Food Sci Nutr, 2014 · checked 2026-09-28
8. gsu8-14 · meta-analysis
   Pooling data from 13 articles with 837 participants indicated that treatment with ginger significantly decreased fasting blood sugar (FBS) (weighted mean difference (WMD) -16.22 mg per 100 mL, 95 % confidence interval (CI) (-25.49, -6.95), I2 = 85.67 %), hemoglobin A1c (HbA1c) (WMD -0.49 %, 95 % CI (-0.86, -0.12), I2 = 98.14 %) ... Ginger was more effective at a daily dose of less than 2000 mg (powdered rhizome of Zingiber officinale administered orally) and in males, individuals younger than 54 years, and individuals with a baseline HbA1c of more than 8 %.
   Acta Pharmaceutica, 2026 · checked 2026-09-29
9. gsu8-09 · systematic review
   While most food, herbs and supplements can be safely taken in moderation, healthcare professionals should be aware of the increased risk of bleeding when taking several food and herbs. These include Chinese wolfberry, chamomile tea, cannabis, cranberry, chitosan, green tea, Ginkgo biloba, ginger, spinach, St. John's Wort, sushi and smoking tobacco.
   Br J Clin Pharmacol, 2021 · checked 2026-09-28
10. gsu8-10 · AHRQ evidence report
    No interactions were noted for AUC∞, Cmax, half-life, clearance and volume of distribution; the GMR 90 percent CIs were not statistically significant, and were within the bioequivalence boundaries of 80 percent to 125 percent (Table 51).
    AHRQ, Dietary Supplements in Adults Taking Cardiovascular Drugs, 2012 · checked 2026-09-28
11. gsu8-05 · meta-analysis
    Fourteen RCTs with 473 subjects were included in our meta-analysis. The results indicated that the supplementation with ginger significantly decreased body weight (BW) (SMD -0.66; 95% CI, -1.31, -0.01; P = 0.04), waist-to-hip ratio (WHR) (SMD -0.49; 95% CI, -0.82, -0.17; P = 0.003), hip ratio (HR) (SMD -0.42; 95% CI, -0.77, -0.08; P = 0.01), fasting glucose (SMD -0.68; 95% CI, -1.23, -0.05; P = 0.03) and insulin resistance index (HOMA-IR) (SMD -1.67; 95% CI, -2.86, -0.48; P = 0.006)
    Crit Rev Food Sci Nutr, 2019 · checked 2026-09-28
12. gsu8-08 · umbrella review
    Taking ginger supplements (usually between 450 and 1950 mg daily) significantly decreases the severity and occurrence of nausea and vomiting compared to a placebo...Numerous studies have shown that ginger does not raise the risk of adverse effects, such as spontaneous abortion or side effects like heartburn and drowsiness, when compared to a placebo or vitamin B6.
    Phytother Res, 2026 · checked 2026-09-28
13. gsu8-03 · meta-analysis
    Eight randomized trials consisting of a total number of 454 participants with T2DM were included in this analysis...The results showed no significant difference in FBS (WMD: 1.38, 95% CI: [-0.53-3.30]; P = .16).
    Medicine (Baltimore), 2019 · checked 2026-09-28
14. gsu8-13 · umbrella review
    Across 10 meta-analyses, ginger supplementation significantly reduced FBS (range of reported WMD: − 0.68 to − 18.81 mg/dL) and HbA1c (range of reported WMD: − 0.27 to − 1.66%) with moderate-to-low certainty. ... No review fulfilled all AMSTAR 2 critical domains.
    Diabetology and Metabolic Syndrome, 2026 · checked 2026-09-29