Early coconut oil exposure suppresses chronic experimental Crohn’s disease via myristic acid and enhanced regulatory T cells

Public health advisory guidelines caution against the consumption of saturated fats, especially coconut oil (CO), yet CO is widely consumed in regions with low inflammatory bowel disease prevalence (IBD) and is often perceived as beneficial by IBD patients. CO is rich in medium-chain saturated fatty acids, notably lauric acid (C12:0) and myristic acid (C14:0) which are negligible in mammalian tissues without dietary intake. Because IBD is linked to saturated fats consumption, here we tested and unexpectedly found that CO and its saturated fatty acids are beneficial suppressing intestinal inflammation in SAMP1/YitFc mice, a chronic IBD model of Crohn’s disease-like ileitis. In young mice, the early exposure to a high-dose CO-based diet prevented ileitis in 63.64% of animals (95%CI = 30.79-to-89.07%). Importantly, comparable protection was observed at lower doses amenable for human translation. Although CO did not reverse established disease in adult mice, when combined with steroids, it prolonged the period of steroid-induced remission illustrating its therapeutic benefits in IBD. Disease prevention was associated with myristic acid and correlated with anti-inflammatory microbiota shifts and enhanced regulatory T-cell responses, without adverse effects. Findings challenge current dietary advisories against CO and support reevaluation of CO and myristic acid as anti-inflammatory dietary adjuvants for the prevention and management of established IBD. Here, the authors show that coconut oil and the fatty acid myristic acid suppress Crohn disease-like intestinal inflammation in mice through multiple mechanisms, supporting a potential role for these dietary fats in promoting protective immune gut responses in Crohn’s disease.