# Residential Greenness, Lifestyle, and Vitamin D: A Longitudinal Cohort of South Asian Origin and Caucasian Ethnicity Women Living in the South of the UK

## TL;DR

This study explores how residential greenness and UV exposure affect vitamin D levels in women of South Asian and Caucasian origin in the UK.

## Contribution

The study links residential greenness to improved vitamin D status in a longitudinal analysis involving two ethnic groups.

## Key findings

- Women in greener areas had a 1.51 times higher likelihood of improved vitamin D status.
- Higher UV exposure was associated with a 2.05 times higher likelihood of improved vitamin D status.

## Abstract

The global population is at risk of vitamin D deficiency due to low exposure to sunlight and low intake of the vitamin through diet. The aim of this study was to investigate in women the association between vitamin D status and parathyroid hormone (PTH), ultraviolet radiation, lifestyle, ethnicity, social conditions, and residential greenness. A 1-year longitudinal study assessed vitamin D status in 309 women living at latitude 51°14′ N. Blood samples were taken four times throughout the year for analysis of 25(OH)D and serum PTH concentration. After each seasonal visit, the individuals completed 4-day diet diaries and used two dosimeter badges for 1 week to estimate weekly UVR exposure. A questionnaire was applied to provide information about lifestyle and their ethnicity. Residential greenness was measured by Normalized Difference Vegetation Index (NDVI), within a 1000 m radius around each participant’s home address. Women living in greener spaces were more likely to have improved vitamin D status (RR: 1.51; 95%CI: 1.13–2.02), as well as those who were more exposed to UVR (RR: 2.05; 95%CI: 1.44–2.92). Our results provide an insight into the connection between residential greenness, lifestyle, and vitamin D status comparing two ethnicities in a country with a temperate climate and with a high degree of urbanization.