Effect of Early Orthodontic Treatment on Body Weight, Dietary Habits, and Physical Activity in Young Adults

Abstract

Background: Fixed orthodontic treatment improves facial esthetics, oral function, and psychosocial well-being in young adults. Beyond dental alignment, early treatment may influence body weight, dietary habits, and physical activity, as appliance-related discomfort often alters chewing patterns and food choices.

Objective: To evaluate the impact of early fixed orthodontic treatment on body weight, dietary habits, and physical activity in young adults.

Methods: A prospective study was conducted at BSMMU from October 2022 to September 2023, including 130 first-time orthodontic patients aged 18–27 years. Anthropometric measurements, dietary patterns, and physical activity levels were assessed at baseline, 1 month, and 3 months post-appliance placement. BMI changes were analyzed using paired t-tests, and associations with diet and activity were assessed with Chi-square tests (p < 0.05). Ethical approval and informed consent were obtained.

 Results: Among 130 participants (mean age 21.3 ± 2.4 years; 59% female), baseline BMI and waist circumference were within normal ranges. During the first three months of treatment, soft-food consumption increased significantly (37.7% → 56.2%, p < 0.001), while hard-food intake decreased (31.5% → 20.0%, p = 0.02). Meal frequency and overall diet balance remained largely unchanged. Changes in food texture were associated with modest BMI fluctuations, whereas physical activity levels were unaffected.

Conclusion: Early fixed orthodontic treatment predominantly affects food texture preferences, resulting in moderate BMI changes, without significantly altering overall diet or physical activity. Awareness of these early modifications can help clinicians provide targeted dietary guidance to support patient health and compliance