Ginger: what the research does and doesn't show

Nausea is ginger's most-studied human use, and even there the trial record depends heavily on what's causing the nausea — chemotherapy, motion sickness and surgery each have separate trials with different results, some positive and some null. Kidney function hasn't been tested in a controlled human trial at all. This page covers the general research picture; diarrhea, constipation, bloating and pregnancy safety each have their own dedicated pages linked below.

What the evidence doesn't support

It doesn't support ginger as a reliable remedy for nausea from every cause — the trials below don't agree with each other, and the cause of the nausea changes the result. It doesn't support any claim about kidney function or kidney health: no controlled human trial testing that question was found. It doesn't support ginger tea as equivalent to any of the doses in the trials below, since every nausea trial used a capsule or powder with a stated milligram amount, not tea. And it doesn't support ginger and turmeric together as a combination with its own studied effect — each ingredient's research below tested it alone, not paired with the other.

What the trials found

Nausea — the research doesn't point one direction. A 2012 double-blind trial randomized 576 cancer patients to placebo or 0.5, 1.0 or 1.5 grams of ginger a day, alongside their standard anti-nausea medication, for six days around each chemotherapy cycle; all three ginger doses reduced nausea severity on the first day more than placebo, with the biggest difference at the two lower doses. A smaller 2016 trial of 119 women with breast cancer, using 500 mg of ginger powder twice daily for three days per cycle, found no meaningful difference in nausea or vomiting scores between ginger and placebo. A small 2003 crossover trial had 13 people with a history of motion sickness sit in a rotating chair with or without a 1,000-2,000 mg ginger pretreatment; ginger reduced the nausea score, delayed how quickly nausea started, and shortened recovery time compared with placebo. And for nausea after surgery, a 2004 meta-analysis pooling six trials and 538 patients found ginger lowered the relative risk of postoperative nausea only slightly (RR 0.84, most of the confidence interval crossing no effect), with the authors concluding ginger isn't a clinically meaningful antiemetic in that setting.

Kidneys. No controlled human trial testing ginger's effect on kidney function was found in the search behind this page.

Ginger and turmeric together. Turmeric and ginger are frequently sold and consumed together, but neither ingredient's research below tested the combination — each trial tested one ingredient alone. See ginger and turmeric for how the two compare, and ginger benefits: what the research does and doesn't show for ginger's individual research.

Trial	Population	Dose	Finding
2012 RCT, n=576	Chemotherapy patients	0.5-1.5 g/day, plus standard antiemetic	Less first-day nausea than placebo, biggest effect at lower doses
2016 RCT, n=119	Breast cancer, chemotherapy	500 mg twice daily	No significant difference from placebo
2003 crossover, n=13	History of motion sickness	1,000-2,000 mg, pretreatment	Less nausea, delayed onset, faster recovery than placebo
2004 meta-analysis, n=538	Postoperative patients, 6 pooled trials	Varied	Only a small, borderline effect vs. placebo

Questions people ask

Does ginger root help with nausea?

It depends on the cause. The trials above found a benefit for chemotherapy-related nausea (at two of three doses tested) and for motion sickness, but no benefit in a separate chemotherapy trial at a different dose, and only a small, borderline effect for nausea after surgery.

Is ginger root good for kidneys?

No controlled human trial testing ginger's effect on kidney function was found. There isn't research here to answer that question either way.

What is ginger root and turmeric good for?

Ginger and turmeric each have their own separate body of research — see ginger and turmeric for how the two compare. Neither ingredient's trials tested the pairing itself, so there's no studied effect specific to combining them.

Can ginger root cause diarrhea or constipation?

This has its own page with the specific research: see does ginger cause diarrhea and how much ginger is too much for what the trials report about digestive side effects at different doses.

Can ginger root help with bloating?

No controlled human trial testing ginger against bloating specifically was found in our search. See does ginger help with GI disease? for the closest related digestive research, including a small trial that found ginger sped up stomach emptying without changing symptom scores.

Is ginger root safe during pregnancy?

This question has its own dedicated page with the full caution-focused answer: see who should not take ginger.

When to talk to a doctor

Persistent or severe nausea, digestive symptoms that don't resolve, or any question about kidney function, pregnancy or a diagnosed condition are reasons to talk to a doctor rather than rely on a supplement — ginger is not a substitute for medical evaluation or treatment of any of these.

Related reading: ginger benefits: what the research does and doesn't show, how much ginger should you take a day, and ginger side effects.