Poor dietary quality prevalent in COPD patients

Patients with chronic obstructive pulmonary disease (COPD) often exhibit low dietary quality, a recent study has shown.

“We recommend that male patients increase their intake of coarse cereals and fruits, while patients living in urban areas should reduce their consumption of alcohol and cooking oils,” said the researchers, who assessed 525 COPD inpatients from 1 December 2022 to 1 December 2023.

They obtained data on dietary intake from food frequency questionnaires and assessed diet quality using the Chinese Healthy Eating Index (CHEI). Disease severity was examined using the Modified Medical Research Council Dyspnea Scale (mMRC), the COPD assessment test (CAT), and the Global Initiative for Obstructive Lung Disease (GOLD) stage.

Finally, the research team analysed the relationship of the total CHEI score and its component scores with COPD disease severity using multivariable logistic regression.

COPD patients had a CHEI score of 56.75. Those in the low CHEI group had a significantly higher CAT score than patients in the high CHEI group (p<0.05). [Asia Pac J Clin Nutr 2025;34:810-820]

In ordinal logistic regression analysis, higher CHEI total scores significantly correlated with the low grade of mMRC (odds ratio, 0.982, 95 percent confidence interval, 0.964‒1.000; p<0.05). Moreover, higher intakes of tubers, whole grains and mixed beans, and fish and seafood correlated with lower mMRC grades (p<0.05).

“CHEI total score and scores of each food component showed that the inclusion of tubers, whole grains and mixed beans, fruits, vegetables, and fish and seafoods in the diet of COPD patients may have a beneficial effect on reducing disease severity in COPD,” the researchers said.

Mechanisms

The association between dietary quality scores and COPD severity can be explained by several mechanisms. For instance, COPD is a progressive disease marked by airflow limitation, which is driven by oxidative stress and inflammation in the lungs. [Front Immuno 2024;15:1404615]

A higher diet-quality score, such as the Recommended Food Score, alternate Mediterranean Diet Score, and Alternate Healthy Eating Index, resulted in lower levels of oxidative stress and inflammation biomarkers. [Eur J Clin Nutr 2011;65:1271-1278; Am J Clin Nutr 2005;82:163-173]

“Thus, diets with higher CHEI scores may reduce COPD disease severity by reducing oxidative stress and inflammation,” the researchers said.

Furthermore, tubers, whole grains and mixed beans, and vegetables contain vitamins, minerals, and dietary fibre, which can help lower inflammation and improve COPD severity. [Nutrients 2024;16:1136; Epidemiology 2018;29:254-260]

“Dietary fibre from whole grains, mixed beans, and tubers reduces serum levels of inflammatory markers such as C-reactive protein and interleukin-6,” the researchers said. [Nutrients 2024;16:1047]

“Fish and seafood are rich in protein, which improves the nutritional status of the patient, and contain omega-3 polyunsaturated fatty acids and minerals that can play a role in reducing inflammation and immunomodulation in the body,” they added. [The J Nutr 2024;155:453-466; Nutrients 2022;14;2115; Nutrients 2024;16;1696]