Schizochytrium is a genus of marine microalgae known for its high content of docosahexaenoic acid (DHA), an omega-3 long-chain polyunsaturated fatty acid. Omega-3 fatty acids, especially DHA and eicosapentaenoic acid (EPA), have been studied for their anti-inflammatory properties and potential benefits in autoimmune and inflammatory diseases such as rheumatoid arthritis (RA).

Most clinical studies on omega-3 supplementation in RA have used fish oil (rich in EPA and DHA), showing modest improvements in joint pain, stiffness, and markers of inflammation. Schizochytrium is increasingly used as a plant-based source of DHA, primarily for vegetarians and vegans. While there is clear evidence that omega-3 supplementation may help in RA, direct clinical trials specifically using Schizochytrium-derived DHA in RA patients are limited. Some animal studies and preclinical models suggest that DHA from Schizochytrium can exert anti-inflammatory effects, but robust, large-scale human trials are lacking.

Therefore, the use of Schizochytrium for RA is based on scientific rationale and extrapolation from broader omega-3 research, but direct evidence is currently limited. The overall evidence rating is 2 out of 5.