Stearic acid supplementation can inhibit the TGF-β/SMAD2/3 signal transduction pathway, which is the main signal transduction mechanism in the progression of pulmonary fibrosis, and can induce the expression of other profibrotic mediators to promote a series of processes, including collagen deposition and extracellular matrix remodeling, synergistically (7, 8). The gene discussed is TGFB1; the disease is pulmonary fibrosis.