Probiotics
Kefir
Also called: kefir grains
A fermented milk drink with many microbes.
- Why people take it
- Gut health.
- What the evidence says
- A healthy food; little disease evidence.
- How it is usually taken
- About one cup a day as a fermented drink.
- Be careful
- Contains milk.
- Medicines it can interact with
- No important medicine interactions are known, but tell your doctor and pharmacist about every supplement you take.
Other probiotics
Common questions
What is Kefir?
A fermented milk drink with many microbes.
Why do people take Kefir?
Gut health.
Does Kefir work?
A healthy food; little disease evidence.
How much Kefir do people take?
About one cup a day as a fermented drink.
Is Kefir safe?
Contains milk.
Does Kefir interact with medicines?
No important medicine interactions are known, but tell your doctor and pharmacist about every supplement you take.
Sources and further reading
Last reviewed 31 October 2026. Written by Satya Babu.
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