Pineapple and Bromelain: What the Research Shows About Digestion and Inflammation

Pineapple is the third most important fruit in global production, but its reputation as a health ingredient rests specifically on bromelain — a mix of protein-digesting enzymes found throughout the fruit, stem, and core. A 2024 review in the Journal of Postharvest Technology pulled together the nutritional and medicinal research on both the whole fruit and bromelain specifically.

Why Bromelain Is the Active Ingredient

About 80% of the nitrogenous compounds in pineapple pulp have proteolytic (protein-breaking) activity, driven by bromelain. It’s recognized by the U.S. National Library of Medicine as a digestive enzyme: taken with meals, bromelain aids the digestion of protein by breaking it down into absorbable amino acids — the same basic function that lets pineapple double as a natural meat tenderizer.

The Anti-Inflammatory Evidence

Osteoarthritis

Bromelain has meaningful clinical trial support for joint inflammation: it has been shown to significantly reduce pain and stiffness in patients with osteoarthritis, and in one head-to-head trial, a combination of bromelain, trypsin, and rutin produced a similar reduction in pain and inflammation to the NSAID diclofenac over six weeks in 103 knee osteoarthritis patients — a genuinely direct comparison against a standard treatment, not just a placebo.

Colonic Inflammation

Bromelain’s anti-inflammatory action extends to the gut specifically: it has been shown to reduce the severity of colonic inflammation, and patients with ulcerative colitis showed significant symptomatic improvement following bromelain treatment in clinical research — directly relevant to digestive-health use.

General Anti-Inflammatory Mechanism

Mechanistically, bromelain has documented analgesic properties linked to its interaction with pain mediators like bradykinin, and it has been shown to modulate immune cell activity and reduce inflammatory cytokine signaling — a genuine biochemical basis for its anti-inflammatory reputation, not just a folk claim.

What Else the Whole Fruit Offers

Beyond bromelain, pineapple is a strong source of vitamin C (half a cup of juice provides about 50% of an adult’s daily target) and manganese, a trace mineral involved in bone and connective tissue formation as well as antioxidant enzyme activity. Pineapple’s antioxidant compounds — including catechin and ferulic acid, concentrated particularly in the peel and core — have been linked to reduced oxidative stress, a contributor to a range of chronic conditions.

The Bottom Line

Pineapple’s health case is really bromelain’s case: a well-documented digestive enzyme with genuine clinical trial support for reducing inflammation, evaluated head-to-head against a standard anti-inflammatory drug in osteoarthritis and shown to help colonic inflammation directly. The whole fruit adds meaningful vitamin C and manganese on top of that, making pineapple one of the more evidence-backed “functional fruits” rather than a purely traditional one.

References
[1] Lalhruaitluangi, N.; Mandal, D. “Medicinal and nutritional characteristics of pineapple in human health: A review.” J. Postharvest Technol. 2024, 12(2), 1–13.