Are Vegan Children Healthier? Massive Study Reveals Which Nutrients Plant-Based Kids Are Most Likely To Miss

Paper: Vegetarian And Vegan Kids Are Leaner With Better Cholesterol, But Lack Critical Nutrients Without Supplements

More families are exploring plant-based diets for their children, but a massive analysis of nearly 50,000 kids reveals a complicated picture. Children eating lacto-ovo-vegetarian and vegan diets tend to be leaner and have better cholesterol profiles than their meat-eating peers, but the review also found higher odds of iron deficiency and anemia in lacto-ovo-vegetarian children, and a much higher risk of vitamin B12 deficiency in vegan children.

The systematic review and meta-analysis examined 59 studies involving 48,626 children under 18 years old from 18 countries. Researchers compared 7,280 lacto-ovo-vegetarian children (those who eat dairy and eggs but no meat), 1,289 vegans, and 40,059 omnivores across dozens of nutritional and health measures.

Lacto-ovo-vegetarian children consumed less energy, protein, fat, vitamin B12, vitamin D, and zinc compared to omnivores. Yet they ate more fiber, iron, folate, vitamin C, and magnesium. Vegan children showed similar patterns, though calcium intake was particularly low.

An important note on the data: dietary intake values in this review reflect food sources without supplementation, while blood test results often included children who took supplements. This helps explain why intake numbers sometimes look low even when blood markers appear adequate. The full paper is published in Critical Reviews in Food Science and Nutrition.

Leaner Bodies, Not Stunted Growth

Lacto-ovo-vegetarian children measured slightly shorter and weighed less than omnivores, with lower BMI scores, less body fat, and reduced bone mineral content. Vegan children also showed shorter stature and lower BMI scores.

Despite these differences, most measurements remained within normal pediatric ranges. Rather than indicating poor health, these patterns reflect a leaner body composition with less fat mass.

The Iron Paradox

Blood tests showed a puzzling contradiction in lacto-ovo-vegetarian children. They typically consumed more dietary iron than omnivores, yet their ferritin levels (iron stores) were lower. Lacto-ovo-vegetarians faced 2.4 times higher odds of iron deficiency and 2.6 times higher odds of anemia.

This happens because plant foods contain only non-heme iron, which the body absorbs far less efficiently than the heme iron found in meat. Compounds in plants like fiber and phytates further block iron absorption, even when total intake appears adequate.

For vegan children, far fewer studies reported iron deficiency or anemia, so the review did not find a clear difference in odds compared with omnivores. However, vegan children did show lower hemoglobin and ferritin levels in the pooled blood test data.

B12 Deficiency Nearly Five Times Higher in Vegans

Vitamin B12 deficiency was the starkest risk for vegan children, who showed nearly five times higher odds of deficiency compared to omnivores. This vitamin is absent from unfortified plant foods, making supplementation or fortified products absolutely essential for vegans.

Studies tracking supplement use confirmed their importance. When vegan children received proper B12 and vitamin D supplementation, their blood levels matched or exceeded those of omnivores.

Lacto-ovo-vegetarian children also showed lower B12 intake, though dairy and eggs provide some protection. Vitamin D levels were significantly lower in lacto-ovo-vegetarians as well, though vitamin D insufficiency affects many children regardless of diet due to limited sun exposure and few dietary sources.

Cardiovascular Benefits Start Early

Across multiple studies, plant-based kids tended to have lower total and LDL cholesterol (the “bad” kind) compared to omnivores. These improvements likely result from higher fiber intake and lower consumption of saturated fat and dietary cholesterol. What that means for heart disease risk decades later remains unknown, since all the studies were snapshots in time rather than long-term follow-ups.

Three Critical Nutrients Beyond B12

Beyond vitamin B12, three other nutrients need close attention. Calcium intake was substantially reduced in vegan children, raising concerns about bone development during critical growth years. Bone mineral content was significantly lower in lacto-ovo-vegetarian children, though more research is needed on vegan bone health.

Iodine was another concern, particularly since plant-based diets often exclude iodine-rich seafood. Using iodized salt provides a simple solution for families raising vegetarian or vegan children.

Zinc intake trended lower in plant-based diets as well. Though clinical zinc deficiency remains rare in wealthy countries, many plant foods high in zinc also contain phytates that inhibit absorption.

The researchers note that calcium, iodine, and zinc often fell at the lower end of recommended ranges, making them nutrients requiring particular attention in plant-based childhood diets.

Global Patterns Show Consistent Trends

The analysis included studies from 18 countries, with the largest numbers from Poland and India. Sixteen studies came from low- and middle-income countries, while 43 originated in high-income settings.

Overall, the patterns were broadly similar across countries. But the authors note one exception: iron intake looked different in the only low- and middle-income study that reported it. They also point out that families in lower-resource settings may have a harder time accessing fortified foods and supplements, which can change how these diets play out in real life.

When Plant-Based Works and When It Doesn’t

Duration of dietary adherence varied widely across studies, from more than one month to lifelong. Most studies used food records, food frequency questionnaires, or interviews to assess what children ate.

Many studies didn’t report whether children took supplements, though 20 documented supplement use and seven provided separate analyses for supplemented versus unsupplemented children. This inconsistency makes interpreting nutritional adequacy challenging.

The studies that reported supplement use suggested a clear pattern: supplements and fortified foods helped close key gaps, especially for vitamin B12. But supplement reporting wasn’t consistent, so it’s hard to generalize across all children.

What This Means for Families

The researchers conclude that lacto-ovo-vegetarian and vegan diets can support healthy childhood growth when properly planned with attention to key nutrients and appropriate supplementation. These eating patterns offer genuine health benefits, including higher fiber intake and better cholesterol levels.

However, without fortified foods or supplements, kids can be more likely to run into problems with vitamin B12 (especially on vegan diets) and iron status (especially for lacto-ovo-vegetarians). The review also flagged vitamin D, calcium, iodine, and zinc as nutrients that often land at the low end of recommended ranges on plant-based diets, so they’re worth planning for.

The study authors note that nutritional inadequacy concerns all dietary patterns, not just plant-based ones. Typical omnivorous diets also frequently lack sufficient fruits, vegetables, and whole grains.

Healthcare providers and policymakers should support families with clear, evidence-based guidance on meeting nutritional needs. Parents need reliable information about which nutrients require supplementation and how to optimize absorption of others.

The research team acknowledges several limitations. All included studies were cross-sectional snapshots rather than following children over time, preventing conclusions about cause and effect. Families choosing plant-based diets may differ from omnivorous families in health consciousness and socioeconomic factors that independently affect outcomes.

Measuring what children actually eat is difficult, with most studies relying on parent reports that may contain errors. For vegan children specifically, many outcomes had limited data from only a handful of studies.

Disclaimer: This article is for general information only and isn’t a substitute for medical advice. If you’re changing a child’s diet, check in with a pediatric clinician or dietitian.