OBJECTIVE: The objective of this study was to investigate the effects of total dietary energy intake on asthma. STUDY SELECTION: The study was a retrospective cross-sectional study of Americans aged 1-18 year. Comprehensive demographic, dietary, examination, laboratory, and asthma questionnaire data were collected for each participant. Multivariate logistic regression, restricted triple spline curves, threshold effects, and stratified analyses were used for analysis. RESULTS: Of 12,090 participants, 1,893 (15.66%) had a diagnosis of asthma. After accounting for potential confounders, compared with the group with the lowest energy intake (Q1), groups 2 (Q2), groups 3 (Q3), and groups 4 (Q4) had adjusted odds ratios (ORs) of 0.72 (0.62-0.85), 0.63 (0.51-0.77) and 0.55 (0.43-0.7) for asthma. The relationship between total energy intake and asthma showed an L-shaped curve (p = 0.001). The results were further verified by stratification and sensitivity analyses. In the threshold analysis, we found that the saturation effect was reached at a total energy intake of 56.442 kcal/kg/day with an OR of 0.981 (0.973-0.989). CONCLUSION: The prevalence of asthma in Americans aged 1-18 years was associated with total dietary energy intake in an L-shaped curve, with a significant turning point found at approximately 56.442 kcal/kg/day.