Plant-Based Diets Don’t Impact Child Growth in First 2 Years, Study Finds

The prevailing concern that plant-based diets may hinder infant growth appears largely unfounded, according to a large-scale retrospective study published in JAMA Network Open on March 5, 2026. Researchers found no significant differences in growth patterns between children raised on vegan, vegetarian, and omnivorous diets up to age 2, challenging some long-held assumptions about nutritional needs during early childhood.

Early Growth Differences, But No Long-Term Impact

The study, led by Kerem Avital, RD, MPH, a PhD candidate at Ben-Gurion University of the Negev, analyzed data from nearly 1.2 million children born in Israel between 2014 and 2023. The cohort included 3,338 children (0.3%) in vegan households, 14,790 (1.2%) in vegetarian households, and the vast majority (98.5%) in omnivorous households. Researchers tracked length, weight, and head circumference measurements up to two years of age.

Initial observations revealed slight differences in birth weight, with infants in vegan and vegetarian families tending to be marginally smaller than those in omnivorous families. Low birth weight was slightly more prevalent in the vegan group (6.1%) compared to vegetarian (5%) and omnivorous groups (4.6%; P < .001). Conversely, high birth weight was more common in the omnivorous group (5.2%) than the vegan group (3.4%; P < .001). Mothers following vegan diets also reported longer durations of breastfeeding (P < .001).

During the first 60 days of life, infants in the vegan and vegetarian groups showed a slightly higher risk of being underweight compared to those in omnivorous families (adjusted OR = 1.37; 95% CI, 1.15-1.63, and aOR = 1.21; 95% CI, 1.11-1.32, respectively). However, these differences dissipated by age 2, with no statistically significant variations in growth observed among the three dietary groups.

Addressing Previous Concerns and Limited Evidence

Avital explained that prior research on the impact of plant-based diets on infant growth was often limited by small sample sizes and conflicting results. Many existing studies included only a few dozen children following vegan diets, making it tough to draw firm conclusions. This new study’s large scale provides a more robust dataset for analysis.

“Before this study, the evidence on how vegan and vegetarian family diets affect infant growth was quite limited,” Avital told Healio. “Critically, no nationwide study had ever tracked growth trajectories longitudinally across vegan, vegetarian and omnivorous families, which meant clinicians had exceptionally little robust evidence to guide their counseling of these families.”

Contextual Factors in Israel

The study was conducted in Israel, a country with universal healthcare and good access to prenatal care. This is an important contextual factor, as nutritional deficiencies are less common in populations with robust healthcare systems. Avital also noted that families choosing vegan diets in Israel tended to be older and have higher incomes, a pattern observed in other Western countries. This suggests that socioeconomic factors may play a role in ensuring adequate nutrition for children on plant-based diets.

What Which means for Families and Clinicians

The findings suggest that well-planned plant-based diets can support healthy growth in infants, at least through the age of two. However, the researchers emphasize the importance of careful planning and nutritional monitoring. It’s crucial for families following vegan or vegetarian diets to ensure their children receive adequate amounts of essential nutrients, such as vitamin B12, iron, zinc, calcium, and vitamin D, which may be less readily available in plant-based foods.

Avital recommends that clinicians shift away from preconceived notions about plant-based diets and engage with families in a more evidence-based and constructive manner. She also stresses the importance of encouraging whole food diets over highly processed vegan substitutes. The 2025-2030 Dietary Guidelines for Americans, released by the HHS in January 2026, also emphasize the importance of whole food nutrition.

Study Details and Limitations

This retrospective cohort study utilized data from the Israeli National Health Database. While the large sample size strengthens the findings, it’s important to acknowledge the study’s limitations. As a retrospective study, it cannot establish cause-and-effect relationships. It’s possible that other factors, not accounted for in the analysis, may have influenced infant growth. The study focused on children up to age 2; long-term effects of plant-based diets on growth and development beyond this age remain to be investigated.

Future Research and Guidance Updates

Further research is needed to explore the long-term effects of plant-based diets on child development and to identify specific nutritional strategies that can optimize growth in infants and young children. Ongoing surveillance of growth patterns in children following different dietary patterns will be crucial for informing clinical guidance. The American Academy of Pediatrics is expected to review these findings as part of its ongoing evaluation of infant nutrition guidelines. Clinicians should stay abreast of updates from reputable organizations like the AAP and the World Health Organization (WHO) regarding infant feeding recommendations. The WHO provides comprehensive guidance on infant and young child feeding, emphasizing the importance of exclusive breastfeeding for the first six months of life and the introduction of complementary foods thereafter.

Kerem Avital, RD, MPH, can be reached at [email protected].