BackgroundWhile the American Academy of Pediatrics advises against low-calorie sweeteners (LCS) consumption by children <5y due to potential health and development concerns, the extent of this consumption among these children is unknown. ObjectivesTo describe the intake, sources, and dietary patterns associated with LCS consumption among U.S. infants and preschoolers. MethodsWe used cross-sectional 24-hour dietary recall data (day 1) among 1,497 children aged 6mo-5y from the National Health and Nutrition Examination Survey (NHANES) 2017-2020 pre-pandemic. Complex survey procedures and sampling weights were applied to compare LCS consumption patterns (prevalence and frequency [times/day] of any LCS, any LCS-containing beverages [LCSBs], and any LCS-containing foods [LCSFs], with each occurrence of consumption= 1 “serving”) across demographic subgroups and to assess the associated nutrients and % of total energy intake (TEI). ResultsThirty-one percent of children 6mo-5y consumed ≥1 LCSB and/or LCSF on a given day. The prevalence of LCS consumption increased with age, 10.5% (6-<12mo) to 34.3% (2-5y). Among LCS consumers, mean serving frequency was 1.4 times/day, with no differences by age or sex. Of all LCSBs servings consumed, 64.0% were fruit drinks; 57.8% of all LCSFs servings were non-Greek yogurt. As consumption levels increased from no LCS to >1 serving/day, intake of the following also increased: total sugar (+1.8% TEI, p-trend=0.04), added sugar (+1.1%, p-trend=0.048), sodium (+304 mg, p-trend=0.04) and fiber (+0.8g, p-trend=0.01). In contrast, protein intake was lower (-0.7% TEI, p-trend=0.02). Those consuming 1 LCS serving/day consumed more total energy than LCS non-consumers (1606 kcal vs. 1401 kcal) but total energy intake did not increase further with >1 LCS serving/day (1607 kcal). LCS consumption was not associated with carbohydrate or fat intake. ConclusionsLCS consumption, primarily from fruit drinks and non-Greek yogurt, is prevalent among U.S. preschoolers, and this consumption is associated with greater intake of total sugar, added sugar, and sodium.