Bromelain is a group of protein-digesting enzymes extracted from pineapple stems and fruit. It breaks down proteins in your gut, reduces inflammation through multiple pathways in your body, and has documented effects on post-surgical swelling, joint pain, sinus congestion, and burn wound healing. Unlike many plant compounds that break apart during digestion, about 40% of bromelain is absorbed from the intestine in a functionally intact form, meaning it enters your bloodstream still active.
How It Breaks Down Protein
Bromelain’s most basic job is splitting proteins into smaller peptides and amino acids. It does this by cutting the chemical bonds that hold protein chains together. This is why it’s sold as a digestive supplement and why fresh pineapple can tenderize meat (and why your mouth sometimes feels raw after eating too much of it).
The enzyme stays active across a wide pH range, roughly 3 to 7, which covers the acidic environment of your stomach and the more neutral conditions of your small intestine. It doesn’t get destroyed during digestion the way many enzymes do. Animal studies have shown that antacids like sodium bicarbonate can further preserve bromelain’s activity as it moves through the digestive tract. For people who struggle to fully digest protein-heavy meals, bromelain supplements can assist the process by doing some of the same work your body’s own digestive enzymes handle.
How It Reduces Inflammation
Bromelain’s anti-inflammatory effects go well beyond the gut. Once absorbed into the bloodstream, it dials down inflammation by targeting two of the body’s main inflammatory signaling chains. Specifically, it reduces the production of key inflammation-driving molecules: the ones responsible for pain signaling, swelling, and tissue redness. It does this in a dose-dependent way, meaning higher amounts produce stronger effects.
In practical terms, bromelain lowers the output of proteins your immune cells release to amplify inflammation. It also suppresses two enzymes that are central to producing the chemicals behind swelling and pain. These are the same enzymes that common anti-inflammatory drugs like ibuprofen target. Bromelain also reduces the activity of an enzyme linked to the production of nitric oxide, another molecule that drives inflammatory responses when overproduced. This multi-target approach is part of why bromelain shows effects across such different conditions, from swollen sinuses to arthritic knees.
Joint Pain and Osteoarthritis
Several clinical trials have compared bromelain head-to-head with diclofenac, a prescription-strength anti-inflammatory commonly used for osteoarthritis. In one double-blind trial of 73 people with knee osteoarthritis, patients taking 540 mg of bromelain daily saw an 80% reduction in pain indices over three weeks, and the improvement held at four weeks after stopping treatment. The bromelain group performed equivalently to the diclofenac group at both time points.
A second randomized trial of 68 patients found that bromelain actually outperformed diclofenac on both pain scores and a combined pain-and-function index. A third trial used a higher dose of 1,890 mg daily and also showed comparable results to diclofenac. These findings matter because diclofenac, while effective, carries risks of stomach ulcers and cardiovascular problems with long-term use. Bromelain appears to offer a similar level of pain relief for mild to moderate knee osteoarthritis with a better side-effect profile.
Swelling After Surgery
Bromelain has a long track record in post-surgical recovery, particularly for reducing edema (the fluid-based swelling that follows tissue injury). A randomized, double-blind trial in orthopedic surgery patients found that a bromelain-containing enzyme therapy produced a 93% reduction in pain and an approximately 90% reduction in inflammation markers by the final visit. Objective blood markers of inflammation dropped significantly as well: C-reactive protein fell by 57% and another inflammatory marker dropped by 61%.
The supplement also outperformed both placebo and a comparison enzyme product in reducing redness, tenderness, local irritation, and wound discharge. This makes it particularly relevant after dental procedures, orthopedic surgeries, and sports injuries where swelling is a primary concern during recovery.
Sinus and Respiratory Congestion
For people with chronic sinusitis, bromelain may help reduce the mucosal inflammation that keeps sinuses swollen and congested. A pilot study of patients with chronic rhinosinusitis found that bromelain tablets improved overall symptom scores, endoscopic appearance of the nasal passages, and quality-of-life measures. The effect was stronger in patients without nasal polyps than in those with them. No adverse events were reported during the trial. Participants took a daily dose of 3,000 FIP units (a measure of enzyme potency) spread across about six tablets.
Burn Wound Care
One of bromelain’s more specialized medical uses is in treating deep burns. A concentrated bromelain-based product has been used on over 10,000 burn patients worldwide for enzymatic debridement, the process of removing dead tissue from a wound so healthy tissue can heal. Unlike surgical debridement, which often cuts away viable skin along with dead tissue, the bromelain-based approach selectively dissolves only the dead layer while preserving the living skin underneath.
The clinical results are striking. Complete removal of dead tissue took one day with bromelain compared to nearly four days with standard surgical care. Half of bromelain-treated patients healed spontaneously without needing a skin graft at all. Among those who did need grafting, the area requiring surgery was dramatically smaller: 13% of the burn surface versus 57% with standard care. Patients also experienced less blood loss, fewer operations, shorter hospital stays, and fewer infections.
What Happens After You Take It
When you swallow a bromelain supplement, it doesn’t simply get digested like food protein. About 40% passes through your intestinal wall in its large, intact molecular form. Once in the bloodstream, it binds to two carrier proteins in your blood and retains its enzyme activity for hours. Research using artificial stomach and blood fluids confirmed that a meaningful concentration of bromelain remains stable after four hours in both environments.
This is unusual for an orally taken enzyme and explains why bromelain can have systemic effects throughout the body rather than only working locally in the digestive tract. Its absorption also increases the blood’s natural ability to break down fibrin, a protein involved in blood clot formation. This fibrinolytic activity is why bromelain can interact with blood-thinning medications. If you take anticoagulants or antiplatelet drugs, the combination could increase bleeding risk.
Dosage and Potency
Bromelain supplements are measured by enzyme activity rather than simple weight. You’ll see labels listing GDU (gelatin digesting units) or MCU (milk clotting units), which tell you how much protein the enzymes can break down, not just how many milligrams are in the capsule. A supplement with a higher GDU per capsule is more potent than one with more milligrams but lower GDU.
Clinical trials have used a wide range of doses. For digestive support, lower doses taken with meals are typical. For inflammation and joint pain, studies have used 540 mg to nearly 1,900 mg of bromelain daily, usually split into multiple doses taken between meals (so the enzymes enter the bloodstream rather than getting used up digesting food). The enzyme is active in your gut between pH 3 and 7, and its activity drops off outside that range. Taking it on an empty stomach is generally recommended when the goal is anti-inflammatory rather than digestive.
Bromelain is well-tolerated in most studies, with side effects rarely reported. The most common are mild digestive symptoms like nausea or diarrhea. People with pineapple allergies should avoid it entirely, and its blood-thinning properties make it worth flagging if you’re on anticoagulant therapy or preparing for surgery.