Ginger

What it is

Ginger is the rhizome (underground stem) of Zingiber officinale, a plant used as a spice and in traditional medicine [1]. Its active compounds include gingerols and shogaols, which the body clears from the blood quickly [1]. Trials used different ginger products, and the reviews note that few reported them clearly, so doses are hard to compare [2].

How it might work

These are proposed mechanisms, not established ones. Reviews describe anti-inflammatory and gastrointestinal-protective activity in ginger's compounds [1]. In a small trial of people with functional dyspepsia, ginger sped up stomach emptying compared with placebo [3]. In a 2025 trial in people with joint pain, ginger changed several inflammatory markers, including IL-6 and C-reactive protein [4].

What the research says

The strongest positive finding is for nausea in early pregnancy. A meta-analysis of 12 randomized trials with 1,278 pregnant women found ginger reduced nausea more than placebo (mean difference 1.20, 95% CI 0.56 to 1.84) [5]. A 2022 meta-analysis of 13 trials (1,174 women) found the same for nausea, with no significant effect on vomiting [6]. An umbrella review of systematic reviews had the greatest confidence in ginger's antiemetic effect in pregnant women [2].

After surgery, a meta-analysis of 14 trials with 1,417 patients found lower nausea severity with ginger than with placebo (mean difference -0.71), and less need for rescue antiemetic drugs (risk ratio 0.71) [7]. A separate meta-analysis of 10 trials (918 patients) found the same for nausea severity (standardized mean difference -0.247) [8]. A 2026 network meta-analysis of 54 trials ranked ginger first among nine non-drug add-on treatments for nausea severity, with low certainty [9].

For period pain, a 2024 meta-analysis of 12 trials found ginger reduced pain intensity more than placebo (standardized mean difference -1.13), and it was no different from NSAID painkillers for pain intensity [10]. An earlier meta-analysis of four placebo trials found ginger powder at 750 to 2,000 mg from the first 3 to 4 days of the cycle reduced pain, which the authors called suggestive evidence [11].

For knee osteoarthritis, a meta-analysis of five placebo-controlled trials (593 people) found ginger reduced pain (standardized mean difference -0.30) and disability (standardized mean difference -0.22) more than placebo [12]. A 2020 review of four trials found pain fell by 7.88 mm more than placebo, but its authors judged the evidence insufficient for pain and function [13]. An umbrella review rated the pain effect in osteoarthritis as small but of high GRADE certainty [2].

In a small trial of 11 people with functional dyspepsia, ginger capsules (1.2 g in total) emptied the stomach faster than placebo, but symptoms did not change [3].

For chemotherapy nausea, results are mixed. A 2025 meta-analysis of 35 trials found ginger capsules added to standard antiemetic drugs reduced grade 3 acute nausea (risk ratio 0.19) [14]. A 2022 review found acute vomiting was less likely with ginger at 1 g a day or less for more than four days, with no difference in acute nausea [15]. A 2013 review of five trials (872 patients) found no significant effect on acute nausea or vomiting [16]. A 2019 update found acute vomiting less likely at 1 g a day or less for more than three days (odds ratio 0.4), with no significant effect on nausea [17].

For blood sugar in type 2 diabetes, results conflict. A 2026 meta-analysis of 13 trials found lower fasting blood sugar (mean difference -16.27 mg/dL) and HbA1c (-0.41%) than placebo, with high variation between trials, and the authors called the size of these effects of limited clinical importance [18]. A 2024 meta-analysis of five trials found no significant pooled effect on fasting blood sugar or HbA1c [19].

For muscle soreness after exercise, results are mixed. A systematic review found about 2 g a day, taken for at least five days, may modestly reduce muscle pain after eccentric (lengthening) resistance exercise and prolonged running [20]. In a trial of 20 people, 4 g a day for five days did not change muscle damage markers or soreness, although strength recovered faster [21]. In a 2025 trial of 30 people with mild to moderate joint pain, 125 mg a day lessened the muscle pain people felt in the thigh during squats [4].

For vomiting in pregnancy, pooled trials did not show a significant effect, though one review reported a trend towards less vomiting [5][6].

For vomiting after surgery, a meta-analysis of 10 trials found the lower vomiting rate with ginger was not statistically significant [8]. A 2019 review of three trials found less vomiting with ginger, but the certainty was very low [22]. A Cochrane review of caesarean section trials rated the evidence on ginger and postoperative vomiting as very uncertain [23].

Doses used in studies

Ginger for nausea in pregnancy was usually taken at 500 to 1,500 mg a day in divided doses [24]. In one meta-analysis, the lower daily dose (under 1,500 mg) seemed to favour nausea relief, a subgroup finding [5]. A 2026 review gives 450 to 1,950 mg a day as the usual range in pregnancy studies [25].

For period pain, trials used 750 to 2,000 mg of ginger powder from the first 3 to 4 days of the cycle [11]. The chemotherapy trials that found less vomiting used 1 g a day or less for more than three to four days [17][15]. In blood sugar trials, doses were 1.2 to 2 g a day for 4 to 12 weeks [19]. For muscle soreness, trials used 4 g a day for five days [21] and 125 mg a day for 58 days [4]. A systematic review of muscle pain used about 2 g a day [20].

An umbrella review reports 0.5 to 3 g a day in capsules for up to three months as the dose consistently reported as effective [2]. The dyspepsia trial used three capsules totalling 1.2 g [3].

Safety and interactions

Side effects: in pregnancy trials, heartburn and drowsiness did not differ significantly from placebo or vitamin B6 [5]. Belching was identified as a possible side effect in pregnant women [24]. In knee osteoarthritis trials, people taking ginger were more than twice as likely to stop treatment as those on placebo (risk ratio 2.33) [12]. One muscle trial found more eosinophils, a type of white blood cell, with ginger [4]. Few trials reported adverse effects at all [26].

Upper limits: no upper safe limit was found in the studies read. One review says there is not enough data to rule out potential toxicity, especially over longer periods [1].

Medicine interactions: a 2021 review of warfarin interactions lists ginger among foods and herbs with a reported increased bleeding risk, and notes that some herbs and supplements were linked to major bleeding, including intracranial bleeding [27]. A 2012 review says serious bleeding events have been associated anecdotally with supplements, but controlled studies are too few to show a consistent anticoagulant effect for ginger [28]. A review of herbs and anticoagulant or antiplatelet drugs lists ginger as altering how these drugs work, but the findings conflict [29]. Reviews of blood-thinner management before surgery include ginger among the supplements to consider [30].

Pregnancy: in a meta-analysis of 12 trials, ginger did not significantly raise the risk of miscarriage compared with placebo, but the estimate was wide (risk ratio 3.14, 95% CI 0.65 to 15.11), so harm is not ruled out [5]. A 2026 umbrella review reports no higher risk of spontaneous abortion or side effects, but rates the included reviews as low methodological quality [25].

Breastfeeding: a Cochrane review of oral galactagogues included ginger among 27 natural options, with very low certainty evidence; the few adverse effects reported were minor [31].

Groups: the studies read did not test ginger in people with bleeding disorders, so safety in that group is not established. The diabetes reviews read do not report safety outcomes [19]. No data were found on kidney disease, liver disease or gallstones in the studies read.

Caveats and open questions

Most trials are small. The reviews of pregnancy nausea trials rate the evidence as low quality [5][32], and the Cochrane review of period pain trials rates the evidence as low or very low quality [26].

Results conflict for chemotherapy nausea, vomiting, blood sugar and muscle soreness, so these claims are graded as mixed [15][19].

In pregnancy, pooled trials did not show ginger to differ significantly from vitamin B6 [6]. For period pain, ginger did not differ from NSAIDs in pooled analysis [10].

Doses and products differ widely between trials, so a best dose is not known [25]. Long-term safety has not been established [25].

One 2025 trial reported that its sponsor had no role in data collection, analysis or the decision to publish [4].

A not-yet-recruiting trial compares tablet ginger with doxylamine for nausea and vomiting (NCT06772974).