Adherence to the planetary health diet reduces dietary costs by 21% supporting affordable healthy eating among older adults in Iran

Abstract Poor dietary patterns among older adults are significantly influenced by socioeconomic status (SES) and food prices, impacting both diet quality and food choice. This study examines how dietary costs relate to the Planetary Health Diet Index (PHDI) and assesses the role of SES in Iran’s eld...

Full description

Saved in:
Bibliographic Details
Main Authors: Maryam Karim Dehnavi, Hanieh Abbasi, Parisa Nezhad Hajian, Ahmadreza Dorosty Motlagh, Leila Azadbakht
Format: Article
Language:English
Published: Nature Portfolio 2025-03-01
Series:Scientific Reports
Subjects:
Online Access:https://doi.org/10.1038/s41598-025-93835-3
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849390337559101440
author Maryam Karim Dehnavi
Hanieh Abbasi
Parisa Nezhad Hajian
Ahmadreza Dorosty Motlagh
Leila Azadbakht
author_facet Maryam Karim Dehnavi
Hanieh Abbasi
Parisa Nezhad Hajian
Ahmadreza Dorosty Motlagh
Leila Azadbakht
author_sort Maryam Karim Dehnavi
collection DOAJ
description Abstract Poor dietary patterns among older adults are significantly influenced by socioeconomic status (SES) and food prices, impacting both diet quality and food choice. This study examines how dietary costs relate to the Planetary Health Diet Index (PHDI) and assesses the role of SES in Iran’s elderly population. In this cross-sectional study, 398 elderly individuals from southern Tehran were sampled. Dietary data were collected using a validated food frequency questionnaire, and adherence to the PHDI was evaluated based on EAT-Lancet guidelines. Food costs were derived from the Iranian Statistics Center and retail prices. Multivariable linear regression analyzed the relationship between PHDI adherence and dietary cost. PHDI adherence varied significantly across demographics. Higher adherence was observed in females (OR = 0.82, 95% CI: 0.71–0.95) and those with a BMI ≤ 27.5 (OR = 0.84, 95% CI: 0.73–0.97), while single individuals had higher scores (OR = 0.85, 95% CI: 0.74–0.98). Higher PHDI tertiles were linked to lower daily dietary cost, with a significant decrease observed in the highest tertile compared to the lowest (β = − 708,367 Rials, 95% CI: − 1,060,371 to − 356,362). However, this association was not significant among single and low-income participants. The study reveals that higher adherence to the PHDI is associated with reduced dietary costs, a key barrier to obtaining a healthy, balanced diet among older adults, and may thereby support better health outcomes, including malnutrition prevention and functional independence. Future research should focus on longitudinal studies to develop equitable public health strategies that promote affordable and sustainable dietary practices.
format Article
id doaj-art-d39f5107b6654702873aeeeef5b7ff8b
institution Kabale University
issn 2045-2322
language English
publishDate 2025-03-01
publisher Nature Portfolio
record_format Article
series Scientific Reports
spelling doaj-art-d39f5107b6654702873aeeeef5b7ff8b2025-08-20T03:41:41ZengNature PortfolioScientific Reports2045-23222025-03-0115111010.1038/s41598-025-93835-3Adherence to the planetary health diet reduces dietary costs by 21% supporting affordable healthy eating among older adults in IranMaryam Karim Dehnavi0Hanieh Abbasi1Parisa Nezhad Hajian2Ahmadreza Dorosty Motlagh3Leila Azadbakht4Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical SciencesDepartment of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical SciencesDepartment of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical SciencesDepartment of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical SciencesDepartment of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical SciencesAbstract Poor dietary patterns among older adults are significantly influenced by socioeconomic status (SES) and food prices, impacting both diet quality and food choice. This study examines how dietary costs relate to the Planetary Health Diet Index (PHDI) and assesses the role of SES in Iran’s elderly population. In this cross-sectional study, 398 elderly individuals from southern Tehran were sampled. Dietary data were collected using a validated food frequency questionnaire, and adherence to the PHDI was evaluated based on EAT-Lancet guidelines. Food costs were derived from the Iranian Statistics Center and retail prices. Multivariable linear regression analyzed the relationship between PHDI adherence and dietary cost. PHDI adherence varied significantly across demographics. Higher adherence was observed in females (OR = 0.82, 95% CI: 0.71–0.95) and those with a BMI ≤ 27.5 (OR = 0.84, 95% CI: 0.73–0.97), while single individuals had higher scores (OR = 0.85, 95% CI: 0.74–0.98). Higher PHDI tertiles were linked to lower daily dietary cost, with a significant decrease observed in the highest tertile compared to the lowest (β = − 708,367 Rials, 95% CI: − 1,060,371 to − 356,362). However, this association was not significant among single and low-income participants. The study reveals that higher adherence to the PHDI is associated with reduced dietary costs, a key barrier to obtaining a healthy, balanced diet among older adults, and may thereby support better health outcomes, including malnutrition prevention and functional independence. Future research should focus on longitudinal studies to develop equitable public health strategies that promote affordable and sustainable dietary practices.https://doi.org/10.1038/s41598-025-93835-3Planetary Health Diet IndexDietary costSocioeconomic status
spellingShingle Maryam Karim Dehnavi
Hanieh Abbasi
Parisa Nezhad Hajian
Ahmadreza Dorosty Motlagh
Leila Azadbakht
Adherence to the planetary health diet reduces dietary costs by 21% supporting affordable healthy eating among older adults in Iran
Scientific Reports
Planetary Health Diet Index
Dietary cost
Socioeconomic status
title Adherence to the planetary health diet reduces dietary costs by 21% supporting affordable healthy eating among older adults in Iran
title_full Adherence to the planetary health diet reduces dietary costs by 21% supporting affordable healthy eating among older adults in Iran
title_fullStr Adherence to the planetary health diet reduces dietary costs by 21% supporting affordable healthy eating among older adults in Iran
title_full_unstemmed Adherence to the planetary health diet reduces dietary costs by 21% supporting affordable healthy eating among older adults in Iran
title_short Adherence to the planetary health diet reduces dietary costs by 21% supporting affordable healthy eating among older adults in Iran
title_sort adherence to the planetary health diet reduces dietary costs by 21 supporting affordable healthy eating among older adults in iran
topic Planetary Health Diet Index
Dietary cost
Socioeconomic status
url https://doi.org/10.1038/s41598-025-93835-3
work_keys_str_mv AT maryamkarimdehnavi adherencetotheplanetaryhealthdietreducesdietarycostsby21supportingaffordablehealthyeatingamongolderadultsiniran
AT haniehabbasi adherencetotheplanetaryhealthdietreducesdietarycostsby21supportingaffordablehealthyeatingamongolderadultsiniran
AT parisanezhadhajian adherencetotheplanetaryhealthdietreducesdietarycostsby21supportingaffordablehealthyeatingamongolderadultsiniran
AT ahmadrezadorostymotlagh adherencetotheplanetaryhealthdietreducesdietarycostsby21supportingaffordablehealthyeatingamongolderadultsiniran
AT leilaazadbakht adherencetotheplanetaryhealthdietreducesdietarycostsby21supportingaffordablehealthyeatingamongolderadultsiniran