Ginger Supplements: Dosage, Benefits and Side Effects

Gingerols and shogaols inhibit cyclooxygenase and lipoxygenase pathways, giving a mild anti-inflammatory action, and act on 5-HT3 receptors in the gut and on gastric motility, which is the basis of the antiemetic effect. Drying and heating convert gingerols to shogaols, so preparation changes the profile.

• Nausea and vomiting: effective across pregnancy, motion sickness, post-operative and chemotherapy-induced nausea. This is its best-supported use.
• Dysmenorrhoea: systematic reviews and meta-analyses support a reduction in menstrual pain.
• Osteoarthritis pain: contested. Meta-analysis of Zingiberaceae extracts found a dose-related pain reduction; a randomised trial of 1 g/day powdered ginger in knee osteoarthritis found nothing.
• Chronic pain generally: modest effect with a linear dose-response across studies.

Lakhan 2015 systematic review and meta-analysis of Zingiberaceae extracts for pain, which found a dose-response relationship, against Bartels 2013 and a randomised trial of powdered ginger in knee osteoarthritis that found no benefit. Systematic reviews of ginger for dysmenorrhoea and for chemotherapy-induced nausea are more uniformly positive.

1-2 g/day of powdered ginger. Nausea trials generally used up to 1 g/day and did not need more. Osteoarthritis trials tend to use 1-2 g/day of standardised extract; the negative trial used 1 g/day of plain powder, which may be part of why the results diverge from the extract literature.

Heartburn, a burning aftertaste, mild GI upset and diarrhoea at higher doses. Well tolerated at food-like doses. Doses above 4 g/day are not well characterised.

Mild antiplatelet activity, so caution alongside warfarin, aspirin and other anticoagulants, and stop before surgery. May lower blood glucose and blood pressure, adding to medication that does the same. In pregnancy, doses up to 1 g/day are the studied range for morning sickness.