Complementary feeding and childhood adiposity in preschool-aged children in a large Chinese cohort

Area of Science:

• Pediatric Nutrition
• Childhood Obesity Epidemiology
• Public Health Research

Background:

• Childhood adiposity is a growing public health concern globally, particularly in rapidly developing regions like Mainland China.
• Complementary feeding practices, including the timing and type of foods introduced, are critical determinants of early childhood growth and development.
• Understanding the relationship between infant feeding and subsequent adiposity is essential for developing effective prevention strategies.

Purpose of the Study:

• To investigate the association between the timing and specific types of complementary feeding and the development of childhood adiposity.
• To evaluate the impact of early versus delayed introduction of complementary foods on body mass index (BMI) z-scores and overweight risk.
• To identify specific complementary foods that may influence childhood adiposity in a Chinese population.

Main Methods:

• A population-based prospective cohort study (Jiaxing Birth Cohort) involving 97,424 singletons enrolled between 1999-2009 in Southeast China.
• Detailed complementary diet information and anthropometric measurements (including BMI-for-age z-score) were collected at 1, 3, and 6 months.
• Follow-up data until 4-5 years of age were used to assess overweight (BMI z-score 1-2) and obesity (BMI z-score ≥2).

Main Results:

• Early introduction of complementary foods (before 3 months) was significantly associated with a greater BMI z-score and increased risk of overweight (OR 1.11).
• Introduction of complementary foods between 4-6 months was used as the reference, with earlier introduction showing a higher risk.
• Early introduction of fish liver oil, a common complementary food, was strongly linked to higher BMI z-scores and increased overweight risk.

Conclusions:

• The timing of complementary feeding, particularly early introduction before 3 months, is associated with increased childhood adiposity.
• Early introduction of fish liver oil is a significant factor contributing to higher BMI and overweight risk in Chinese children.
• Findings suggest that current recommendations for complementary feeding timing may need to be emphasized to mitigate childhood adiposity risks.