Supplement
Bromelain
Bromelain alone has been tested in placebo-controlled trials for knee osteoarthritis pain and for inflammation markers, and showed no benefit.
Grade D, tested: a human randomized trial looked for a benefit on the endpoint The outcome a trial measures to decide whether the treatment worked, such as heart attacks, blood pressure or a symptom score. graded and did not find one. How to read a grade →
Bromelain is an enzyme from pineapple. It is sold to ease swelling and joint pain. When bromelain alone was tested against a dummy pill in knee arthritis, it did not help. In adults with diabetes, it did not lower signs of swelling in the blood. Studies that looked better used mixed enzyme products, not bromelain alone.
- Dose studied
- No standardized dose established
- Form graded
- Bromelain (from pineapple stem)
- Cited PMIDs PubMed ID: the permanent number the US National Library of Medicine gives a published paper. Each one links to that paper's record on PubMed.
- PMID 40803821 →
A letter describes the human evidence, not the product, the manufacturer, or the ingredient's worth.
See the full evidence record →This was not skipped. A human randomized trial has tested it and did not find a benefit on the endpoint below. That is a different statement from an untested intervention, which may still turn out to work. A Route 1 No human randomized trial has been run, so the record rests on animal or mechanistic evidence only. One of the two routes to the lowest letter on EBL's scale. Grade D means nobody has looked. A Route 2 Grade D means somebody looked and the answer was no.
Population 47 adults with moderate to severe knee osteoarthritis, bromelain 800 mg/day for 12 weeks
Certainty Low to moderate. Small single placebo-controlled trial; null.
PMID 17121765 →
Population Adults with diabetes, bromelain 1,050 mg/day for 12 weeks
Certainty Low. Small exploratory placebo-controlled trial; null.
PMID 27412590 →
Bromelain for inflammation and osteoarthritis pain, usually studied in combination formulas rather than alone.
Why this gradeGrade D, tested, no benefit. The reasoning, and what the grade does not cover.
Grade D, Route 2: tested alone and no benefit. The only placebo-controlled trial of bromelain alone in knee osteoarthritis (Brien et al., QJM, 2006; PMID 17121765) was null, and a placebo-controlled trial in adults with diabetes found no effect on inflammation markers (Ley et al., Chin J Integr Med, 2016; PMID 27412590). The trial previously cited tested a combination product and cannot grade bromelain. Moved from C in October 2026 by editor adjudication; Route 2 rather than Route 1 because a bromelain-alone placebo An inactive substitute made to look like the real treatment, so participants cannot tell which one they received. trial exists and was null.
WHAT THIS GRADE DOES NOT COVERenzyme combination products that contain bromelain with other ingredients, which are different interventions; and swelling after dental or sinus surgery, where bromelain-alone trials exist and are not graded on this record.
A grade describes the human evidence for a named use. It is not advice, and it is not a judgment on any individual prescription. How the letters are decided →
Who responds: this record's trial reading reports no subgroup that identifies who responds.
How this letter has changed · latest: October 2026 · Downgraded
Bromelain held a C on a trial of a three-ingredient enzyme product (Henrotin et al., RMD Open 2025; PMID 40803821) sponsored by the product's maker. The bromelain-alone search found two placebo-controlled trials on the graded uses and both were null: Brien et al. (QJM 2006; PMID 17121765) in knee osteoarthritis and Ley et al. (Chin J Integr Med 2016; PMID 27412590) on inflammation markers. Tested alone, no benefit: D on Route 2. Editor adjudication, October 2026.PMID 40803821 PMID 17121765 PMID 27412590
Every change to a letter on this site is dated and published. The full evidence log →
Commercial disclosure
EBL earns no commission on any supplement it grades. A purchase made through the dispensary link below pays EBL nothing, the practitioner discount goes to you in full. The dispensary is Fullscript, a practitioner dispensary, and many of the professional-grade brands in it are sold mainly through practitioners rather than in health food stores. Grades are assigned by published rubric before any commercial relationship exists and are never influenced by one. Full disclosure.
No dose is published here. This record carries no authored dose, because the cited trials do not converge on a single figure. Each trial cited on this page states the dose it used, and EBL has not turned those into a recommendation.
Standardized extracts/forms were used in the cited trials; product quality varies.
In the cited trial of an enzyme combination containing bromelain, three tablets were taken in the morning and three in the evening, at least 30 minutes before or 90 minutes after a meal (PMID 40803821).
Checked against the full published report. What the cited trials did, not a schedule. Every supplement, by trial timing →
Raised bleeding risk. Pineapple allergy. Separation from surgery is the usual clinical margin.
Anticoagulants and antiplatelets. Bromelain reduces platelet aggregation and has fibrinolytic activity in laboratory and animal work; there is no human trial quantifying the interaction, so this is a mechanistic caution. Bromelain also increases blood levels of some antibiotics, notably amoxicillin and tetracyclines.
Bromelain reduces platelet aggregation in laboratory work. Bromelain reduces human platelet aggregation in vitro and thrombus formation in animals. No human trial has measured the interaction with an anticoagulant, so this is a mechanistic caution. Metzig et al. (In Vivo, 1999; PMID 10218125): bromelain proteases reduce human platelet aggregation in vitro, adhesion to endothelial cells, and thrombus formation in rat vessels.
VAS pain scores and swelling measurements at the affected site at baseline and 4 weeks for inflammation applications. For post-surgical or injury recovery, document swelling circumference at standardized anatomical points weekly. Drug interactions: bromelain potentiates anticoagulants and certain antibiotics.
Primary evidenceThree papers, each linked to its PubMed record.
Brien et al. (QJM, 2006; PMID 17121765): randomized double-blind placebo-controlled trial, 47 adults with moderate to severe knee osteoarthritis, bromelain alone 800 mg/day for 12 weeks; no difference from placebo on WOMAC or any subscale. Ley et al. (Chin J Integr Med, 2016; PMID 27412590): randomized placebo-controlled trial, bromelain alone 1,050 mg/day for 12 weeks in adults with diabetes; no effect on fibrinogen or CRP. Henrotin et al. (RMD Open, 2025; PMID 40803821): randomized trial of a three-ingredient product (bromelain with trypsin and rutoside), fully sponsored by the company that supplied the product; it grades the combination, not bromelain.
Educational use only · Not medical advice · Starting, stopping or changing any supplement or medication is a decision for your physician
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. The grade on this page describes the strength of published human trial evidence in the populations studied. It is not a recommendation for any individual and is not medical advice. Starting, stopping or changing any supplement or medication is a decision for your physician.
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How EBL searched for the trials (1 search)
The search that was run, what it returned, and what was left out and why, so the absence of evidence can be checked as well as its presence.
bromelain[tiab] AND randomized controlled trial[pt] NOT (trypsin[tiab] OR rutoside[tiab] OR rutin[tiab])Grades move when new trials publish. A free monthly email lists every grade EBL moved, with the reason and the trial behind it: the sign-up is on the Evidence Log →