Abstract
Background
Vegetarian diets are becoming increasingly popular among Canadians, yet few studies have evaluated the relationship between a vegetarian diet and childhood growth and nutritional status. Since vegetarian diets can be less energy dense and may have lower micronutrient content, we hypothesized that a vegetarian diet may affect childhood growth including lower adiposity and height, as well as lower micronutrient stores.
Objectives
The primary objective of this study was to evaluate the relationship between vegetarian diet and growth, including adiposity and height among healthy children 6 months to 10 years of age. Secondary objectives included the examination of the relationship between vegetarian diet and iron and vitamin D stores. We also explored whether cow’s milk intake or age modified the associations between vegetarian diet and growth, and micronutrient stores.
Design/Methods
This was a prospective cohort study of healthy children age 6 months to 10 years. The primary exposure was vegetarian diet measured by parent report. The primary outcome was BMI z-score. Secondary outcomes included height-for-age z-score, serum ferritin, and serum 25-hydroxyvitamin D. Anthropometric measures and venous blood samples were collected at health supervision visits by trained research assistants. Linear mixed effect modelling was used to determine the association between vegetarian diet, growth, and micronutrient stores.
Results
A total of 8912 children (n = 248 vegetarian) participated. In the adjusted models there was no evidence of an association between vegetarian diet and BMI z-score (p = 0.605, 95% CI: -0.06, 0.10), height-for-age z-score (p 0.057, 95% CI: -0.16, 0.002), serum ferritin (p = 0.768, 95% CI: -3.84, 2.84), or 25-hydroxyvitamin D (p = 0.204, 95% CI: -2.14, 0.46). The relationship between vegetarian diet and serum 25-hydroxyvitamin D was modified by child age. Volume of cow’s milk intake did not modify the relationships between vegetarian diet and BMI z-score, height-for-age z-score, serum ferritin, or 25-hydroxyvitamin D. In a secondary analysis, we examined adiposity through weight status categories and found children with a vegetarian diet had higher odds of being underweight (BMI z-score <-2) (OR 1.9, p = 0.006, 95% CI 1.21-3.00).
Conclusion
In this prospective cohort study, evidence of an association between vegetarian diet and lower BMI z-score, height-for-age z-score, and micronutrient stores was not found. Our results suggest children with vegetarian diets had higher odds of being underweight. Future research is needed to evaluate dietary factors and patterns of children following vegetarian diets, especially those with an underweight weight status.
Correction: Serum 25-Hydroxyvitamin D Concentrations ≥40 ng/ml Are Associated with >65% Lower Cancer Risk: Pooled Analysis of Randomized Trial and Prospective Cohort Study
