Short answer: They are studied for different things. NIH says ginger may help nausea in pregnancy and possibly menstrual cramps, while turmeric or curcumin has positive early evidence for knee osteoarthritis but no definite benefit for any use.12 Curcumin is poorly absorbed, and better-absorbed forms have been linked to liver damage.2 We found no trial comparing them.
| Curcumin (turmeric) | Ginger | |
|---|---|---|
| Plant | Turmeric, a plant in the ginger family; curcumin gives the yellow color2 | Zingiber officinale rhizome1 |
| What NIH says may help | Knee osteoarthritis (initial evidence positive); not enough to conclude for any use2 | Nausea and vomiting in pregnancy; possibly menstrual cramps and knee osteoarthritis1 |
| What does not seem to help | Unclear for most other conditions2 | Most motion sickness studies showed no help1 |
| Absorption | Free curcumin mostly undetectable in blood after 500 to 8,000 mg3 | No single figure in the sources checked |
| Side effects | Nausea, reflux, stomach upset, diarrhea or constipation2 | Abdominal discomfort, heartburn, diarrhea, mouth irritation1 |
| Liver | Liver damage reported with better-absorbed formulations2 | Not flagged by NCCIH |
| Pregnancy | Supplements may be unsafe2 | Supplements may be safe; ask your provider1 |
Curcumin and turmeric: NCCIH says several meta-analyses on knee osteoarthritis are positive so far but higher-quality evidence is needed, early research hints at effects on fatty liver measures and mouth sores from cancer treatment, and overall there is not enough to definitely conclude a benefit for any health purpose.2
Ginger: NCCIH says research shows it may help nausea and vomiting in pregnancy and might reduce menstrual cramp severity, while it is uncertain for chemotherapy or post-surgery nausea and most motion sickness studies showed no help.1
We found no trial comparing the two for the same condition.
Very little free curcumin reaches the blood. In one study no curcumin was detected after single doses of 500 to 8,000 mg.3 In another, after 10 or 12 g, only one person had detectable free curcumin; its conjugates peaked at about 3.3 hours.4 Products are often combined with piperine from black pepper to raise absorption, and NCCIH says liver damage has been reported with such better-absorbed forms. Stop and call your provider if you notice fatigue, dark urine or yellow skin.2
NCCIH says ginger has been used safely in many studies.1 For either, ask your provider first if you take any medicine. More detail: the Curcumin and Ginger (Zingiber officinale) guides.