Vitamin D supplementation and gross motor development: A 3-year follow-up of a randomized trial

Area of Science:

• Pediatric Nutrition
• Developmental Pediatrics
• Public Health

Background:

• Vitamin D status is linked to gross motor development (GMD) in pregnancy, early childhood, and by season of birth.
• Understanding the impact of infant vitamin D intake and birth season on GMD is crucial.

Purpose of the Study:

• To investigate the effects of varying vitamin D3 supplementation doses (400, 800, 1200 IU/day) during infancy on GMD in early childhood.
• To determine if season of birth interacts with vitamin D intake to influence GMD.

Main Methods:

• A 3-year follow-up of a single-center trial involving 116 healthy infants supplemented with vitamin D3 from 1 to 12 months.
• Gross motor development was assessed at age 3 using the Peabody Developmental Motor Scales-2, measuring gross motor quotient (GMQ) and subtest scores.

Main Results:

• 94% of children had normal GMQ scores (≥85).
• An interaction between vitamin D dosage and season of birth (p=0.01) was found for GMQ and stationary scores; 1200 IU/day showed higher scores in winter/spring born children compared to 400/800 IU/day.
• Object manipulation scores were higher in the 1200 IU/day group versus the 400 IU/day group (p=0.04).

Conclusions:

• Standard infant vitamin D supplementation (400 IU/day) adequately supports GMD, irrespective of birth season.
• A higher dose of 1200 IU/day may offer a modest benefit for GMD in winter/spring born infants, meriting further research.
• These findings contribute to understanding optimal vitamin D intake for pediatric motor development.