The Association between a Healthy Diet and Quality of Life Results from the Population-Based FinHealth 2017 Study ^†

Abstract

Background and objectives: In general, a healthy diet is a key lifestyle factor when it comes to guaranteeing a good quality of life (QOL). Evidence of the association between overall diet and QOL in the general adult population, however, remains limited. Consequently, our aim was to assess whether better overall diet quality is associated with better QOL in Finnish adults. Method: This cross-sectional study was based on the nationally representative FinHealth 2017 Study. Our study population comprised 4846 men and women aged 25 or older. Diet was assessed with a validated 134-item food-frequency questionnaire (FFQ). Overall diet quality was measured by the modified Baltic Sea Diet Score (mBSDS; range 1–22; higher scores indicated better diet quality) consisting of eight components: fruits, vegetables, whole-grain products, low-fat milk, fish, red and processed meat, fat quality, and alcohol. QOL was measured using the EUROHIS-QOL 8-item index (EUROHIS-8). The overall EUROHIS-8 score was calculated by summing the scores for the eight items. The mean value (range 1–5; a higher value indicated a better QOL) of the overall EUROHIS-8 score was used. The mean values of overall EUROHIS-8 according to quintiles of mBSDS based on predictive margins were analyzed using linear regression models adjusted for age, sex, education, marital status and energy intake. The sampling design and non-response were taken into account. Results: Higher dietary quality was associated with better QOL. The EUROHIS-8 mean values increased consistently from the first quintile (Q1) to the fifth (Q5) of mBSDS: Q1 3.88 (95% CI 3.84, 3.93); Q2 3.96 (3.92, 4.00); Q3 3.97 (3.93, 4.02); Q4 4.04 (4.00, 4.09); Q5 4.10 (4.07, 4.14) (p for trend < 0.01). The results were similar for both sexes and for younger (<65 years) and older age groups. Discussion: These findings suggest that a healthy diet is associated with better QOL. Our results reinforce the earlier evidence by providing new findings based on large, population-based data, standardized measures and focusing on overall diet quality as exposure. From the public health perspective, it is important to reveal the full potential of a healthy diet in improving QOL.