Association between noncow milk beverage consumption and childhood height

Background: Cow milk consumption in childhood has been associated with increased height, which is an important measure of children's growth and development. Many parents are choosing noncow milk beverages such as soy and almond milk because of perceived health benefits. However, noncow milk contains less protein and fat than cow milk and may not have the same effect on height. Objective: We sought to determine whether there is an association between noncow milk consumption and lower height in childhood and assess whether cow milk consumption mediates the relation between noncow milk consumption and height. Design: This was a cross-sectional study of 5034 healthy Canadian children aged 24-72 mo enrolled in the Applied Research Group for Kids cohort. The primary exposure was the volume of noncow milk consumption (number of 250-mL cups per day). The primary outcome was height, which was measured as height-for-age z score. Multivariable linear regression was used to determine the association between noncow milk consumption and height. A mediation analysis was conducted to explore whether cow milk consumption mediated the association between noncow milk consumption and height. Results: There was a dose-dependent association between higher noncow milk consumption and lower height (P < 0.0001). For each daily cup of noncow milk consumed, children were 0.4 cm (95% CI: 0.2, 0.8 cm) shorter. In the mediation analysis, lower cow milk consumption only partially mediated the association between noncow milk consumption and lower height. The height difference for a child aged 3 y consuming 3 cups noncow milk/d relative to 3 cups cow milk/d was 1.5 cm (95% CI: 0.8, 2.0 cm). Conclusions: Non cow milk consumption was associated with lower childhood height. Future research is needed to understand the causal relations between noncow milk consumption and height.