Resistant Potato Starch Supplementation Increases the Serum Levels of Choline and Sphingomyelins Without Affecting Trimethylamine Oxide Levels

<b>Background/Objectives:</b> The prebiotic effect of resistant potato starch (RPS) has been demonstrated, but the role of this nutrient in choline metabolism and the production of microbially modified choline-derived toxins is unknown. <b>Methods:</b> We performed post hoc analysis comparing changes in choline and related metabolites in serum from baseline to the week 4 time point in a human clinical trial evaluating daily consumption of 3.5 g RPS versus a placebo. <b>Results:</b> Choline levels increased in the RPS consuming group, while levels of trimethylamine decreased and levels of the cardiovascular toxin trimethylamine oxide were unaffected by RPS consumption. Increases in choline were positively correlated with increases in <i>Akkermansia</i> in the gut. Oxidation of choline to betaine was unaffected by RPS, as was acetylcholine metabolism. Levels of various saturated even acyl chain and hydroxylated acyl chain sphingomyelins were increased in RPS consuming participants, and levels of phospholipid degradation products phosphocholine and glycerophosphocholine were decreased. <b>Conclusions:</b> These data suggest that RPS enhances choline absorption without increasing TMAO and stimulates the incorporation of choline into sphingomyelins containing saturated even acyl chains and hydroxylated acyl chains. Future studies assessing the physiological consequences, such as cognitive or neurological benefits, of enhanced choline absorption and sphingomyelin levels in people consuming RPS are warranted.