A study of nearly 9,000 children found those who eat a vegetarian diet had similar measures of growth and nutrition as meat-eating kids. However, they had almost two-fold higher odds of being underweight, which is defined as below the third percentile for Body Mass Index (BMI).
The study, published in Pediatrics and led by researchers at St Michael’s Hospital of Unity Health Toronto, said this highlighted the need for special care when planning the diets of vegetarian youngsters.
The findings come as a shift to consuming a plant-based diet grows in Canada. In 2019, updates to Canadaʼs Food Guide urged Canadians to embrace plant-based proteins, such as beans and tofu, instead of meat.
“Over the past 20 years we have seen growing popularity of plant-based diets and a changing food environment, with more access to plant-based alternatives. However we have not seen research into the nutritional outcomes of children following vegetarian diets in Canada,” said Dr Jonathon Maguire, lead author of the study and a paediatrician at St Michaelʼs Hospital.
“This study demonstrates that Canadian children following vegetarian diets had similar growth and biochemical measures of nutrition compared with children consuming non-vegetarian diets. But vegetarian diet was associated with higher odds of underweight weight status, underscoring the need for careful dietary planning for children with underweight when considering vegetarian diets.”
Researchers evaluated 8,907 children age six months to eight years. The children were all participants of the TARGet Kids! cohort study and data were collected between 2008 and 2019. Participants were categorised by vegetarian status – defined as a dietary pattern that excludes meat – or non-vegetarian status.
Researchers found children with a vegetarian diet had similar mean body mass index (BMI), height, iron, vitamin D, and cholesterol levels as those who consumed meat. The findings showed evidence that children with a vegetarian diet had almost two-fold higher odds of having underweight, which is defined as below the third percentile for BMI.
There was no evidence of an association with overweight or obesity.
Underweight is an indicator of under-nutrition, and may be a sign that the quality of the childʼs diet is not meeting his or her nutritional needs to support normal growth. For children who eat a vegetarian diet, the researchers emphasised access to healthcare providers who can provide growth monitoring, education and guidance to support their growth and nutrition.
International guidelines about vegetarian diet in infancy and childhood have differing recommendations, and past studies that have evaluated the relationship between vegetarian diet and childhood growth and nutritional status have had conflicting findings.
“Plant-based dietary patterns are recognised as a healthy eating pattern due to increased intake of fruits, vegetables, fibre, whole grains, and reduced saturated fat; however, few studies have evaluated the impact of vegetarian diets on childhood growth and nutritional status. Vegetarian diets appear to be appropriate for most children,” said Maguire, who is also a scientist at MAP Centre for Urban Health Solutions at St Michaelʼs Hospital.
A limitation of the study is that researchers did not assess the quality of the vegetarian diets. The researchers note that vegetarian diets come in many forms and the quality of the individual diet may be quite important to growth and nutritional outcomes.
The authors say further research is needed to examine the quality of vegetarian diets in childhood, as well as growth and nutrition outcomes among children following a vegan diet, which excludes meat and animal derived products such as dairy, egg, and honey.
Vegetarian Diet, Growth, and Nutrition in Early Childhood: A Longitudinal Cohort Study
Laura Elliott, Charles Keown-Stoneman, Catherine Birken, David Jenkins, Cornelia Borkhoff, Jonathon Maguire on behalf of the TARGet KIDS! COLLABORATION
Published in Pediatrics on 2 May 2022
The primary objective of this study was to examine the relationships between vegetarian diet and growth, micronutrient stores, and serum lipids among healthy children. Secondary objectives included exploring whether cow’s milk consumption or age modified these relationships.
A longitudinal cohort study of children aged 6 months to 8 years who participated in the TARGet Kids! cohort study. Linear mixed-effect modelling was used to evaluate the relationships between vegetarian diet and BMI z-score (zBMI), height-for-age z-score, serum ferritin, 25-hydroxyvitamin D, and serum lipids. Generalised estimating equation modelling was used to explore weight status categories. Possible effect modification by age and cow’s milk consumption was examined.
A total of 8,907 children, including 248 vegetarian at baseline, participated. Mean age at baseline was 2.2 years (SD 1.5). There was no evidence of an association between vegetarian diet and zBMI, height-for-age z-score, serum ferritin, 25-hydroxyvitamin D, or serum lipids. Children with vegetarian diet had higher odds of underweight (zBMI <−2) (odds ratio 1.87, 95% confidence interval 1.19 to 2.96; P = .007) but no association with overweight or obesity was found. Cow’s milk consumption was associated with higher nonhigh-density lipoprotein cholesterol (P = .03), total cholesterol (P = .04), and low-density lipoprotein cholesterol (P = .02) among children with vegetarian diet. However, children with and without vegetarian diet who consumed the recommended 2 cups of cow’s milk per day had similar serum lipids.
Evidence of clinically meaningful differences in growth or biochemical measures of nutrition for children with vegetarian diet was not found. However, vegetarian diet was associated with higher odds of underweight.
See more from MedicalBrief archives: