PlainPill

Kefir

People mainly take Kefir for mood, digestion, focus. Based on 31 first-hand reports and 22 meta-analyses & systematic reviews in the medical literature. Ranked #193 of 1,974 overall.

43
User score
Mostly positive
48% positive0% mixed0% negative52% unclear

Of reports that state an outcome, 100% are positive.

Clinical research
AStrong research base
22
meta-analyses
34
RCTs
1,419
papers

What Kefir does, according to users

Of the people who reported each effect, the share who said it got better.

What the research says

Systematic reviews and meta-analyses from PubMed, with their published conclusions.

AStrong research base

3+ meta-analyses or systematic reviews and 10+ randomized controlled trials in humans. The grade measures how much human research exists — read the conclusions below for what it found.

Oxid Med Cell Longev · 2021 · Meta-analysis / systematic review
Bioactive Compounds from Kefir and Their Potential Benefits on Health: A Systematic Review and Meta-Analysis

Conclusion: The mechanisms of their action were diverse, indicating that they can act by different signaling pathways. Still, industrial and artisanal kefir may differ regarding functional potential-OR of 8.56 (95% CI: 2.27-32.21, P ≤ .001)-according to the observed health effect, which can be associated with differences in the microbial composition between both types of kefir.

PubMed 34745425 ↗
Nutr Rev · 2023 · Meta-analysis / systematic review
The effects of kefir consumption on human health: a systematic review of randomized controlled trials

Conclusion: Kefir is a dairy product with a unique microbiological profile that appears to be a safe for generally healthy populations to consume. However, efficacy and safety data from high-quality human trials are essential before any recommendations may be made for conditions of the oral and gastric microbiota and metabolic health.

PubMed 35913411 ↗
Arch Iran Med · 2015 · Meta-analysis / systematic review
Kefir and Cancer: A Systematic Review of Literatures

Conclusion: The results of this systematic review suggest that kefir may be associated with cancer prevention and it also has beneficial effects in cancer treatment. This protection may be associated with kefir bioactive components including peptides, polysaccharides and sphingolipids.

PubMed 26621019 ↗
Cochrane Database Syst Rev · 2021 · Meta-analysis / systematic review
Interventions for the management of abdominal pain in Crohn's disease and inflammatory bowel disease

Conclusion: We found low certainty evidence that transcranial direct current stimulation may improve pain intensity compared to sham stimulation. We could not reach any conclusions on the efficacy of any other interventions on pain intensity, pain frequency, and treatment success. The certainty of the evidence was very low due to the low numbers of studies and participants in each comparison and clinical heterogeneity amongst the studies. While no serious or total adverse events were elicited explicitly with any of the treatments studied, the reported events were very low. The certainty of the evidence fo

PubMed 34844288 ↗

Dosage people report

As stated by users — not a recommendation. Follow the label or your doctor.

dailyas reported
1 cupevery night
500 mldaily
2 cupsdaily

Reported side effects

How often each side effect came up across all reports.

stomach issues ×1nausea ×1

What users say

Verbatim quotes, shortened only — each links to the original discussion.

“The first time I tried Kefir it felt like a drug. I really felt it get to my stomach and it felt great. Now when I have it, it can cheer me up”
Source discussion ↗
“Make your own Kefir at home with raw milk. A minor commitment but one of the best health habits in my arsenal.”
Source discussion ↗
“drinking kefir has more beneficial GI effects than taking a probiotic pill”
Source discussion ↗
“Some versions of Kefir that are strong (have high bio count). Most are not. Wallaby (unflavored) is my favorite. All of those make me feel great.”
Source discussion ↗
“Kefir grains (or other fermented cultures) will make you a lifetime supply of way stronger than OTC probiotics”
Source discussion ↗
Top discussions (5)

Other options for mood

User data from public discussions; research from PubMed. Information only, not medical advice — talk to a doctor before starting, stopping or combining anything. Data updated October 2, 2026. How we rate