Ginger

This is the one claim where ginger clears the bar that most botanicals never reach. Health Canada's own monograph lists it not as a traditional use but as a clinically shown one: ginger 'helps prevent nausea and vomiting associated with motion sickness, and/or seasickness.' Regulators are conservative about that wording, and the fact that it survived review tells you something.

The research behind it goes back a long way. The earliest well-known trial, published in the Lancet in 1982 by Mowrey and Clayson, put volunteers prone to motion sickness in a tilted rotating chair and compared powdered ginger against dimenhydrinate (the drug in most travel-sickness pills) and placebo; ginger outperformed the drug on how long people could tolerate the spinning. In 1988 Grontved and colleagues ran a controlled trial on the open sea with naval cadets, which is about as real-world as motion sickness research gets. Later comparative trials, including Schmid's 1994 comparison of seven commonly used seasickness agents and Riebenfeld's 1999 double-blind comparison against dimenhydrinate, kept ginger in the same conversation as conventional options. All of these are cited in the Health Canada monograph.

The most mechanistically interesting is Lien's 2003 study in the American Journal of Physiology. Thirteen volunteers with a history of motion sickness were made nauseous in a controlled way - seated inside a rotating drum that creates the illusion of self-motion - in a randomised, double-blind, placebo-controlled crossover design, meaning each person served as their own comparison. Pretreatment with 1,000 mg or 2,000 mg of ginger delayed the onset of nausea, reduced its peak intensity, and measurably reduced the abnormal stomach electrical rhythm and the vasopressin surge that accompany it. This matters because it shows ginger changing an objective physiological signal, not just a self-reported feeling.

The honest limitation: these are mostly small studies, some are decades old, and the induced-nausea models aren't a perfect stand-in for a rough ferry crossing. But the direction is consistent, and it's backed by a regulator.

Ginger is probably the most-studied natural approach to nausea and vomiting in pregnancy, and the results are genuinely encouraging - with real caveats about study quality.

The most useful single trial is Smith's 2004 study, published in Obstetrics & Gynecology. Researchers enrolled 291 women who were less than 16 weeks pregnant and experiencing nausea, and randomly assigned them to either 1.05 g of ginger per day or 75 mg of vitamin B6 per day for three weeks. Vitamin B6 was chosen as the comparator because it is a standard, doctor-recommended option - so this was a test of whether ginger could hold its own against real care, not against a sugar pill. It could: ginger reduced nausea, dry retching and vomiting to an equivalent extent as vitamin B6.

Zooming out, Viljoen and colleagues published a systematic review and meta-analysis in Nutrition Journal in 2014, pooling 12 randomised controlled trials covering roughly 1,200 pregnant women. Their conclusion was that ginger significantly improved nausea symptoms compared with placebo, and that around 1 g per day taken for at least four days was associated with a substantially higher likelihood of improvement. Two findings from that review are worth stating plainly. First, ginger reduced the feeling of nausea but did not significantly reduce the number of vomiting episodes - so it takes the edge off rather than switching it off. Second, and importantly for safety, ginger did not increase side effects or adverse events, and showed no increased risk of spontaneous abortion compared with either placebo or vitamin B6.

The limitations the reviewers themselves flagged: a modest number of trials, inconsistent ways of measuring nausea between studies, and an overall low quality of evidence rating. Most trials used around 1 g/day of dried ginger for a short period in the first trimester.

Where that leaves us: this is a well-worn, widely used option with reassuring safety data, but it is not a Health Canada-approved indication and it is not something to self-prescribe at extract-level doses. Practitioner-guided, around 1 g a day, short term.

Two very different clinical settings, both tested properly, both landing in roughly the same place: a real but partial benefit, as an addition to standard care rather than a replacement for it.

On surgery: Chaiyakunapruk and colleagues published a meta-analysis in the American Journal of Obstetrics and Gynecology in 2006 that pooled five randomised trials, 363 patients in total, all of which used a fixed dose of at least 1 g of ginger given before surgery. Compared with placebo, ginger reduced the incidence of nausea and vomiting in the 24 hours after gynaecological or lower-limb surgery. Post-operative nausea is one of the most common and most miserable complications of anaesthesia, so even a modest reduction is meaningful - but 363 patients across five trials is a small pool, and later reviews have been more cautious about how large the effect really is.

On chemotherapy: the standout is Ryan's 2012 study in Supportive Care in Cancer, run through the University of Rochester's community oncology network. This was a large, double-blind, multicentre trial: 744 cancer patients were randomised to placebo or one of three ginger doses - 0.5 g, 1.0 g or 1.5 g per day - taken as capsules twice daily for six days, starting three days before chemotherapy began. 576 patients were included in the final analysis. Crucially, every patient also received a standard 5-HT3 antiemetic drug on treatment day, so this tested ginger as an add-on to proper anti-sickness medication, not instead of it. All ginger doses significantly reduced the severity of acute nausea on day one compared with placebo, with the biggest reductions at the lower 0.5 g and 1.0 g doses - not the highest. That dose pattern is worth noting: more was not better.

What this does not mean: ginger is not a treatment for cancer or for surgery, and nobody should substitute it for prescribed antiemetics. It also isn't a Health Canada-permitted claim. These are research findings about symptom severity, in patients already under medical care, and anyone in either situation should be talking to their oncology or surgical team before adding anything - particularly given the bleeding considerations around surgery.

This is ginger's oldest job and the one Health Canada recognises as a traditional use: 'traditionally used in Herbal Medicine (as a carminative) to help relieve digestive upset including lack of appetite, nausea, digestive spasms, indigestion, dyspepsia, and flatulent colic.' A carminative, in old herbal language, is something that helps move trapped gas and settle a griping gut.

What's unusual is that modern measurement broadly agrees with the tradition. Wu and colleagues published a study in the European Journal of Gastroenterology & Hepatology in 2008 in which 24 healthy volunteers were each studied twice, in randomised double-blind fashion. After an eight-hour fast they took either three ginger capsules totalling 1,200 mg or identical placebo, and an hour later drank 500 ml of low-nutrient soup. Researchers then used ultrasound at frequent intervals over 90 minutes to watch the stomach directly - measuring the area of the antrum (the lower stomach), the fundus, and the frequency of the contractions that push food onward. Ginger accelerated gastric emptying and stimulated antral contractions. In plain terms: the stomach cleared faster and squeezed more.

A 2019 systematic review of clinical trials of ginger in gastrointestinal disorders, published in Food Science & Nutrition, gathered this and related work together. Its overall read is that ginger has a supportive role across several digestive complaints, with the strongest and most consistent evidence in nausea and vomiting, and thinner, more mixed evidence for conditions such as functional dyspepsia and irritable bowel.

The honest framing: the mechanism is well demonstrated, the traditional use is long and consistent across TCM, Ayurveda and Western herbalism, and the regulator permits the claim on traditional grounds. What we don't have is a large body of trials showing that speeding up gastric emptying reliably translates into people with chronic indigestion feeling better long term. For a heavy meal, a sluggish stomach or a poor appetite, it's a sensible and well-supported thing to reach for. For a persistent digestive problem, it's a support, not an answer - and persistent symptoms need investigating.

Ginger's anti-inflammatory reputation is the reason a lot of people try it, so it's worth being precise about what has actually been shown.

The landmark trial is Altman and Marcussen's 2001 study in Arthritis & Rheumatism. 261 patients with osteoarthritis of the knee and moderate-to-severe pain took part in a randomised, double-blind, placebo-controlled, multicentre trial lasting six weeks. After a washout period to clear existing painkillers, participants took either a standardised, highly concentrated extract of two ginger species - Zingiber officinale plus Alpinia galanga, coded EV.EXT 77 - or placebo, twice daily, with acetaminophen permitted as rescue medication. The ginger group had a modestly greater reduction in knee pain on standing. It was a genuine, well-run trial, and the effect was genuine - but modest, and achieved with a specific standardised two-species extract, not ordinary ginger powder.

Bartels and colleagues pooled the field in a meta-analysis published in Osteoarthritis and Cartilage in 2015, combining five placebo-controlled trials in patients with mainly knee or hip osteoarthritis. Ginger came out statistically better than placebo for pain, with a standardised mean difference of -0.30, and for physical function at -0.22. In everyday language, an effect of that size is small - noticeable across a group, but not something most individuals would describe as dramatic. The reviewers also noted that people taking ginger were more likely than those on placebo to drop out because of side effects, mostly digestive ones, though all reported adverse events were mild and reversible.

So: a real signal, consistently in the right direction, from decent trials. But small effects, short durations, specific extracts, and a tendency for stomach complaints at the doses used. Health Canada permits no joint, pain or anti-inflammatory claim for ginger, and neither do we. If joint comfort is your main goal, treat ginger as a possible small contributor within a broader plan, not the centrepiece - and don't stop anything your doctor has prescribed.

Long before anyone measured a gastric slow wave, ginger was classified by what it felt like: warming. In Traditional Chinese Medicine fresh ginger is Sheng Jiang and dried ginger is Gan Jiang, and they are treated as two different herbs rather than two forms of one - fresh being used to release exterior cold and settle the stomach, dried being hotter and more inward-warming. That distinction, arrived at centuries ago by taste and observation, turns out to line up with the chemistry: drying converts gingerols into the sharper, hotter shogaols. It's one of the more satisfying places where old classification and modern analysis agree.

In Ayurveda ginger is vishwabhesaj, sometimes translated as 'the universal medicine,' used to kindle agni - digestive fire - and as a near-universal supporting herb in formulas. Western herbal medicine, through Ellingwood, Felter and Lloyd, and Potter's Cyclopaedia, used it as a carminative, a warming stimulant, and an expectorant for coughs and colds. Health Canada actually carries that last one as a permitted traditional claim too: ginger is '(traditionally) used in Herbal Medicine (as an expectorant and cough suppressant) to help relieve bronchitis as well as coughs and colds.'

What we can honestly say about the warming and circulation side: it is a consistent, cross-cultural traditional characterisation with thousands of years behind it, and it is the reason ginger tea is what people reach for on a cold, miserable day. What we cannot say is that there are controlled human trials showing ginger improves circulation. The subjective warmth is real and immediate - that's the pungent compounds acting on heat-sensing receptors. The broader claim is tradition, and we're labelling it as such.