Children who ate healthier plant foods had slightly lower blood pressure later

by · News-Medical

A Dutch study examines how the foods children choose within plant-based diets relate to later heart health and estimated food costs.

Want to read later? Download your clean, ad-free, print-friendly PDF copy by clicking here.

A recent study in The American Journal of Clinical Nutrition examined the relationship between plant-based diet quality, cardiometabolic health, metabolic profiles, and dietary costs in children.

Cardiometabolic Diseases and the Role of Plant-Based Diets in Pediatric Health

Cardiometabolic diseases, including cardiovascular disease, type 2 diabetes, hypertension, and dyslipidemia, share risk factors such as obesity, insulin resistance, and chronic inflammation. Together, they drive significant global morbidity and mortality. While genetics play a role, diet is a major modifiable factor influencing these conditions.

Plant-based diets (PBDs), such as vegetarian, vegan, and flexitarian patterns, center on nutrient-dense plant foods while limiting or excluding animal products. In adults, adherence to healthy, flexible PBDs is associated with reduced cardiometabolic risk, whereas unhealthy PBDs, high in refined grains and sweets, are associated with higher risk.

Cardiometabolic risk factors and dietary habits established in childhood often persist into adulthood, pointing to the importance of early dietary interventions. Most pediatric studies focus on strict PBDs, which may improve body composition and lipid profiles but can also elevate the risk of nutrient deficiencies. Evidence on the effects of gradual, flexible dietary transitions toward plant-based eating in children remains limited.

Previous research links healthy, flexible PBDs to better nutrient profiles and body composition in youth, but their associations with other cardiometabolic markers (e.g., blood pressure, insulin, lipid profiles) remain unclear. The true costs and affordability of healthy PBDs for children, particularly across different socioeconomic contexts, have not been adequately evaluated.

Contributions of food group cost across dietary patterns by quintiles: Mean cost contributions (%) of each food group to the total dietary cost across quintiles (Q1–Q5) of dietary patterns. PDI, plant-based diet index; hPDI, healthful plant-based diet index; uPDI, unhealthful plant-based diet index; DQS, diet quality score. DQS was included to allow comparison of plant-based diet indices with a guideline-based dietary quality index.

Examining the Relationships Between PBD Types and Cardiometabolic Outcomes

The current research is part of the Generation R Study, a large population-based cohort in Rotterdam, Netherlands, involving 9778 pregnant women (2002–2006). At age 8, parents of 7660 children received a food-frequency questionnaire (FFQ); 4785 responded, with 4731 providing valid dietary data. Of those, 3990 had at least one cardiometabolic outcome at age 10 and were included in analyses.

Dietary intake at age 8 was measured using a validated FFQ that covered the frequency and amounts of 71 foods and included 27 additional questions, over the previous 4 weeks. Three plant-based diet indices (PDIs) were created: overall (PDI), healthful (hPDI), and unhealthful (uPDI), adapted for Dutch children.

Foods were grouped into healthy plant-based, unhealthy plant-based, or animal-based categories. The indices measured the relative intake of these food groups; they did not indicate whether children followed vegetarian, vegan, or flexitarian diets. At age 10, anthropometrics, blood pressure, and blood biomarkers were measured. A subset of 402 children underwent targeted metabolomics, yielding 181 standardized metabolite measures after quality control.

Dietary costs were calculated by matching FFQ data to 2017 Dutch retail prices, using the lowest regular prices and accounting for preparation and waste. These were estimated food costs, not records of what families spent. Multivariable linear regression assessed how diet at age 8 was associated with cardiometabolic and metabolite outcomes at age 10, adjusting for relevant child and maternal factors. Analyses also explored links between plant-based diet indices, dietary costs, and a general healthy diet score (DQS).

Diet quality, cardiometabolic markers, and estimated costs

A total of 3990 children were followed for an average of 1.6 years. Children with higher hPDI scores tended to have a European background, come from families with higher socioeconomic status, participate more in sports, and spend less time on screens. Children with higher uPDI scores were more likely to have lower socioeconomic status, participate less in sports, and have more screen time. Overall, children included in the main analysis generally had higher socioeconomic status than those excluded.

After adjusting for confounders, higher hPDI was associated with lower systolic and diastolic blood pressure. The observed differences were small in these generally healthy children. All plant-based diet indices were linked to lower total cholesterol, and higher overall PDI was also associated with lower non-HDL cholesterol.

Higher hPDI was also associated with lower HDL cholesterol, but the study did not establish what this meant for cardiovascular health. There were no significant associations between plant-based diet indices and triglyceride or insulin levels, and hPDI was not associated with the total cholesterol-to-HDL ratio.

Metabolite analysis identified 14 metabolites significantly associated with plant-based diet indices after multiple-testing correction in an exploratory sample of 402 children. Higher overall PDI was linked to lower levels of the amino acids valine and lysine, while higher uPDI was associated with reduced levels of nine specific phospholipids and three short-chain acylcarnitines. These results showed distinct metabolic profiles across the diet indices but did not establish a causal pathway.

Among these 14 metabolites, nine phospholipids were positively associated with total cholesterol, seven with HDL cholesterol, and five with non-HDL cholesterol. Several phosphatidylcholine diacyl (PC.aa) and phosphatidylcholine acyl-alkyl (PC.ae) measures were correlated, suggesting that some findings reflected overlapping signals.

No significant associations were found between amino acids or short-chain acylcarnitines and cholesterol outcomes. Because metabolites and cholesterol were measured at the same visit, the analysis could not determine whether the metabolites explained the cholesterol findings.

Higher uPDI was associated with lower estimated daily food costs, while a higher DQS was associated with higher costs. Neither overall PDI nor hPDI showed a significant association with cost. This suggests that less healthy plant-based diets tended to be less expensive under the study’s standardized pricing model.

Across all diet patterns, processed and red meats, sweets and desserts, fruits, and vegetables consistently contributed the most to total dietary costs. As hPDI increased, a greater proportion of dietary cost came from healthy plant-based foods, with less spent on animal-based and unhealthy plant-based foods. With higher uPDI scores, a greater share of estimated costs came from unhealthy plant-based foods and a smaller share from healthy ones, while costs associated with animal-based foods remained stable.

Sensitivity analyses generally supported the direction of the main findings, with some qualifications. The association between uPDI and HDL cholesterol differed by sex, but was not significant in either boys or girls alone.

Results were similar across different body size measures, except that the association between hPDI and systolic blood pressure weakened after adjustment for body fat percentage at age 10. The association between uPDI and lower dietary cost was slightly weaker among children whose mothers had a university education. The cost associations remained similar in direction after accounting for inflation and calendar year.

The study measured diet only once, used non-fasting blood samples, and included a relatively small metabolomics subset. The authors also noted possible residual confounding and selection toward families with higher socioeconomic status. Because prices came from a separate database, the cost estimates cannot establish what participating families spent or whether a diet was affordable to them.

Conclusions

The current study found that higher healthful plant-based diet scores were associated with modestly lower blood pressure and total cholesterol, but not with estimated dietary costs. Higher unhealthful scores were associated with lower estimated costs and a distinct metabolite profile, but also with lower total cholesterol, making a uniformly unfavorable interpretation difficult.

These results cannot establish the effects of changing a child’s diet or predict long-term health outcomes. Longer-term research is needed to assess the clinical meaning of the observed differences.

Journal reference: