Boswellia

Last reviewed October 2026 · Based on 20 studies

Bottom line

Boswellia extract, made from the resin of the Indian frankincense tree, may ease knee osteoarthritis pain and stiffness, and some trials show better joint function. The trials are mostly small, several were run or funded by companies that sell the extracts, and the products differ, so the size of any benefit is uncertain. Serious side effects were not reported in trials lasting up to 180 days.

What it helps with

Eases knee osteoarthritis pain — Benefit, evidence grade C (Limited). Several meta-analyses and small placebo-controlled trials show pain benefit; downgraded for risk of bias (low-quality trials, several funded by extract makers) and indirectness (proprietary extracts).
Improves knee function — Benefit, evidence grade C (Limited). Meta-analysis and small trials show better function; downgraded for risk of bias and indirectness, with few long-term trials.
Improves knee cartilage on imaging — Benefit, evidence grade C (Limited). Two small trials of specific extracts showed imaging changes; a surrogate outcome with small samples and company-linked authors.
Eases exercise-related muscle and joint pain — Benefit, evidence grade C (Limited). One single-dose trial in healthy adults of a turmeric and boswellia combination; indirect for boswellia alone.
Shortens acute diarrhoea — Benefit, evidence grade C (Limited). One small, placebo-controlled trial of a lecithin-based extract; authors include the extract maker's employees.
Causes side effects — No effect, evidence grade C (Limited). Meta-analyses and trials found no more adverse events than placebo; downgraded for risk of bias as several trials were run or funded by extract makers.

What it is

Boswellia serrata, also known as Indian frankincense, is a medicinal plant whose gum resin is used in traditional medicine [1]. Supplements are standardised extracts, for example to a percentage of 3-O-acetyl-11-keto-beta-boswellic acid [2].

How it might work

Proposed mechanism: boswellic acids may reduce inflammation. In one trial, the extract lowered high-sensitivity CRP and other inflammatory and cartilage-breakdown markers in blood, which is consistent with this idea but does not prove it [3][4].

What the research says

Meta-analyses of placebo-controlled trials found boswellia reduced knee osteoarthritis pain and stiffness and improved function. A 2020 meta-analysis of seven trials (545 people) found lower WOMAC pain and stiffness scores, and better function, than a control group of placebo or standard medicine [5]. A 2025 network meta-analysis of 39 trials (4,599 people) ranked boswellia highest for pain and stiffness [6]. A 2018 meta-analysis of 11 trials found boswellia and curcumin beat placebo for pain and function, but rated the evidence as low quality, with most trials under 100 people [7].

Individual trials point the same way. A 120-day trial of 48 people found improved function and less pain and stiffness than placebo [4]. An eight-week trial of 60 people found reduced pain and stiffness and better physical function [1]. A 180-day trial of 80 people found MRI cartilage volume increased more than placebo [3].

In other uses, a turmeric and boswellia mix relieved exercise-related muscle and joint pain within about an hour in a single-dose trial of 232 healthy adults [8], and a lecithin-based boswellia product shortened acute diarrhoea by about 1.4 days in one trial [9].

Doses used in studies

Trials used 100 mg a day of a standardised extract for 30 to 180 days [2][3][1]. A 90-day trial used 300 mg of Boswellia serrata gum resin extract with 250 mg of celery seed extract [10]. A five-day diarrhoea trial used 250 mg a day of a lecithin-based form [9]. These are doses from trials, not recommendations.

Safety and interactions

Meta-analyses found no increase in side effects compared with placebo [6][11]. Trials lasting 90 to 180 days reported no serious adverse events or safety problems [4][10][3].

The studies reviewed did not report an upper intake limit or a toxic dose [4][3]. None of the studies reviewed reported on pregnancy or breastfeeding [4][3]. The trials reviewed did not report interactions with medicines [4][3]. Trials enrolled adults aged 40 to 75 with mild to moderate knee osteoarthritis [1]; outcomes for people with kidney, liver or bleeding disorders were not reported in the abstracts reviewed [1][3]. People taking blood thinners or other pain relievers should ask a doctor first.

Caveats and open questions

The evidence is limited. The 2018 meta-analysis judged the trials low quality and too small for clinical recommendations [7]. Many trials test branded, proprietary extracts such as Aflapin and Boswellin, so results may not carry over to other products [12][4]. Several trials were funded by, or run by staff of, the companies that make the extracts [10][4]. Most trials lasted 30 to 180 days, and the 2025 review called for larger trials with standard doses and long-term follow-up [6].