Cetylated fatty acids (CFAs), particularly cetyl myristoleate, have been investigated for their potential benefits in inflammatory conditions like rheumatoid arthritis (RA). The primary purported mechanism involves modulation of inflammatory pathways and improvement of joint lubrication and mobility. Several small-scale clinical studies and pilot trials have assessed topical and oral formulations of CFAs in the management of arthritis symptoms.

For example, a randomized, double-blind, placebo-controlled study by Hesslink et al. (2002) evaluated a cetylated fatty acid topical cream in patients with osteoarthritis and reported improvements in knee range of motion and function. However, most of the available evidence is focused on osteoarthritis rather than RA specifically. Data on CFAs in RA are limited, with only a few open-label or small studies suggesting potential symptom relief, primarily related to pain and mobility rather than disease modification. The anti-inflammatory effects observed in vitro and in animal models have not been robustly demonstrated in large, high-quality human trials for RA.

Systematic reviews and rheumatology guidelines currently do not recommend cetylated fatty acids as a standard or adjunctive therapy for RA due to insufficient evidence. Overall, while there is some scientific investigation into CFAs and arthritis, the quality and quantity of evidence, especially for rheumatoid arthritis, remains low.