Dietary quality and cardiometabolic indicators in the USA: A comparison of the Planetary Health Diet Index, Healthy Eating Index-2015, and Dietary Approaches to Stop Hypertension

Abstract

Background The Planetary Health Diet Index (PHDI) measures adherence to the sustainable dietary guidance proposed by the EAT-Lancet Commission on Food, Planet, Health. To justify incorporating sustainable dietary guidance such as the PHDI in the US, the index needs to be compared to health-focused dietary recommendations already in use. The objectives of this study were to compare the how the Planetary Health Diet Index (PHDI), the Healthy Eating Index-2015 (HEI-2015) and Dietary Approaches to Stop Hypertension (DASH) relate to cardiometabolic risk factors. Methods and findings Participants from the National Health and Nutrition Examination Survey (2015–2018) were assigned a score for each dietary index. We examined disparities in dietary quality for each index. We used linear and logistic regression to assess the association of standardized dietary index values with waist circumference, blood pressure, HDL-C, fasting plasma glucose (FPG) and triglycerides (TG). We also dichotomized the cardiometabolic indicators using the cutoffs for the Metabolic Syndrome and used logistic regression to assess the relationship of the standardized dietary index values with binary cardiometabolic risk factors. We observed diet quality disparities for populations that were Black, Hispanic, low-income, and low-education. Higher diet quality was associated with improved continuous and binary cardiometabolic risk factors, although higher PHDI was not associated with high FPG and was the only index associated with lower TG. These patterns remained consistent in sensitivity analyses. Conclusions Sustainability-focused dietary recommendations such as the PHDI have similar cross-sectional associations with cardiometabolic risk as HEI-2015 or DASH. Health-focused dietary guidelines such as the forthcoming 2025–2030 Dietary Guidelines for Americans can consider the environmental impact of diet and still promote cardiometabolic health.

Sociodemographic Trends in Planetary Health Diets among Nutrition Students in Türkiye: Bridging Classroom to Kitchen

“…In another study conducted by Cacau et al in the Brazilian population, the average PHDI score was 60.4, which seems relatively high compared to other countries, but is far from meeting the recommendations [11]. In a recent study, mean PHDI was lower (p < 0.001) in men than in women (44.0 and 47.1, respectively) and tended to be lower in younger individuals [17]. On the contrary, in this study, there was no statistical difference between the total PHDI scores of the participants according to their gender, and the average PHDI total score of the participants under the age of 20 was significantly higher than that of the other age groups (Table 1).…”

“…Considering the statements of the Food and Agriculture Organization [15] that food production must increase in order to meet the needs of the increasing global population [16], it becomes inevitable that updated nutritional guidelines should be created by prioritizing the principle of sustainability. To justify the inclusion of sustainable dietary patterns in these guidelines, the need to compare the PHDI with health-oriented dietary recommendations currently in use has been reported [17]. One of the most commonly used indexes to compare the compliance of individuals' diets with healthy eating recommendations is the Healthy Eating Index (HEI), which was developed to compare compliance with the Dietary Guidelines for Americans [18].…”

“…One of the most commonly used indexes to compare the compliance of individuals' diets with healthy eating recommendations is the Healthy Eating Index (HEI), which was developed to compare compliance with the Dietary Guidelines for Americans [18]. HEI-2020, the latest version of the updated index according to the guide, scores according to threshold values defined according to healthy nutrition recommendations but does not discourage the consumption of animal-sourced foods [17,18]. Additionally, for the HEI, nutritional differences have been demonstrated by gender, income, education, and race/ethnicity [19][20][21].…”

“…Additionally, for the HEI, nutritional differences have been demonstrated by gender, income, education, and race/ethnicity [19][20][21]. However, it is emphasized that the evidence for inequalities in PHDI is insufficient [10,17].…”

“…In addition, levels of awareness about diet quality and planetary health tend to be higher in women than in men, in older age groups than young age groups, and in those with higher socioeconomic status than in those with lower socioeconomic status. The region of residence may have a positive or negative effect on diet quality and PHDI scores by restricting access to food or depending on income level [7,17,22].…”