Asian (Panax) and American ginseng roots are used for energy and fatigue. Products differ a lot in ginsenoside content.
Calculator Official intake Study doses Best form Safety Sources
This is not an essential nutrient, so there is no official daily intake. Only study doses are shown.
These are doses tested in research, not personal advice. Some exceed the upper limit because they were short courses or given under medical care.
2,000 mg a day
A meta-analysis of 12 trials (1,298 patients) found ginseng reduced disease-related fatigue a little. In cancer-related fatigue, American ginseng at 2,000 mg a day for up to 8 weeks helped; study quality varied.
No best form
Why: Studies used standardised extracts with stated ginsenosides (for example 5% or 7%); results do not transfer between types.
Ginseng tea and roots.
American ginseng may interfere with warfarin. Ask your doctor if you take diabetes medicines.
Long-term safety is not well studied.
Pregnant, breastfeeding, on medication, or managing a health condition? Check with a doctor or pharmacist before starting a supplement.
Values checked: November 12, 2026.