Early Weight Gain Forecasts Accelerated Eruption of Deciduous Teeth and Later Overweight Status during the First Year.

OBJECTIVES To determine whether early diet and weight gain velocity have independent or interactive effects on deciduous teeth emergence and overweight status during the first year. STUDY DESIGN Monthly measures of anthropometry and teeth eruption were collected during 1-year trial (0.5-12.5 months) on formula-fed (FF) infants in which the type of randomized infant formula (cow milk or extensively hydrolyzed protein) diet significantly affected early (0.5-4.5 months) weight gain velocity. Generalized linear mixed models determined whether early diet and weight gain velocity had independent or interactive effects on timing and pattern of teeth eruption. Data from a trial on breastfed (BF) infants were used to explore effects of breast milk versus infant formula diets on teeth eruption and overweight status at 10.5 months. RESULTS Independent of infant formula diet, velocities of weight gain had direct effects on the age of first deciduous tooth (P < .04) and number of erupted teeth over time (P<0.002). Greater velocity of weight gain from 0.5 to 4.5 months caused earlier and more frequent eruption of deciduous teeth from 4.5 to 12.5 months. Exploratory follow-up analyses on the BF and FF diet groups found early weight gain velocity (P=0.001), but not diet or its interaction, had significant effects. Infants in the upper quartile for weight gain velocity had more primary teeth (P=0.002), and a greater proportion of them were overweight (P<0.001) at 10.5 months. CONCLUSIONS Faster weight gain accretion forecasted accelerated primary teeth eruption and increased percentage of children who were overweight-risk factors for dental caries and obesity.