# Is it time to align adolescent diets with the Planetary Health Diet? An observational study on early cardiovascular health

## TL;DR

Adhering to the Planetary Health Diet in adolescents is linked to lower risks of high blood pressure and other heart-related issues.

## Contribution

This study is the first to explore the association between a sustainable plant-based diet and cardiometabolic health in adolescents.

## Key findings

- High PHDI adherence reduces risk of high blood pressure by 81% in adolescents.
- PHDI adherence is linked to significant reductions in triglycerides, cholesterol, and blood glucose.
- Mixed models show inverse associations between PHDI and BMI z-score, glucose, and triglycerides.

## Abstract

As the impact of early adoption of a sustainable plant-based diet on cardiometabolic biomarkers remains unexplored, we assessed whether they are associated with the Planetary Health Diet Index (PHDI) in adolescents.

This prospective study was conducted within the SI! Program for Secondary Schools trial (SI! Program) in 886 adolescents (12 years ± 0.4 at cohort entry; 49.1% female) followed during 4 years in Spain. The PHDI scores were derived from validated food frequency questionnaires. Multivariable-adjusted Cox proportional-hazards models (HRs) analyzed the association between PHDI and risk of new-onset high blood pressure (BP), obesity, and elevated plasma cardiometabolic biomarkers. Additionally, mixed models assessed changes in those parameters.

High adherence to the PHDI(Q4 vs. Q1) is associated with a reduced risk of high BP by 81% (HR: 0.19 [95% CI: 0.11, 0.34]), plasma glucose by 47% (HR: 0.53 [95% CI: 0.48, 0.58]), triglycerides (TG) by 66% (HR: 0.34 [95% CI: 0.18, 0.65]), total cholesterol by 51% (HR: 0.49 [95% CI: 0.34, 0.69]), and non-high density lipoprotein cholesterol (non-HDL-C) by 74% (HR: 0.26 [95% CI: 0.13, 0.50]) in Cox models. Mixed models show inverse associations with higher PHDI and blood glucose (−5.23 mg/dL [95% CI: −10.35, −0.10]), TG (−2.48 mg/dL [95% CI: −3.65, −1.30]), and body mass index (BMI) z-score (−0.02 [95% CI: −0.03, 0.00]).

This study stands out as greater adherence to the PHDI is inversely associated with cardiometabolic biomarkers in adolescents, highlighting nutritional benefits of the Planetary Health Diet and its role in preventing the development of cardiovascular diseases and early detection.