Lungs

Healthier plant-based diets come with less COPD and fewer asthma symptoms

By WhyStopHarmingAnimals.com

Smoking is the main cause of chronic obstructive pulmonary disease, but diet moves the risk too[1][2][3][4]. In several large cohorts, healthy plant-based eating tracked with lower COPD risk[1], cured meat tracked with higher risk after smoking was accounted for[3], and the same kind of diet came with fewer new asthma symptoms[5].

Plants and COPD

In the UK Biobank, reported in Nutrients in 2025, healthier plant-based eating patterns came with lower COPD risk[1]. Unhealthy plant-based patterns went the other way and raised it[1]. The kind of plant food matters[1].

A study of 44,335 men, published in Thorax in 2017, looked at fruit and vegetables specifically[2]. Men who ate five or more servings a day had about 40% lower COPD risk if they were current smokers and 34% lower if they were ex-smokers[2]. Smoking still did the most damage, and diet shifted the risk within each group[2].

Cured meat and COPD

Cured meat went the opposite direction[3][4]. In the Health Professionals Follow-up Study, men who ate the most cured meat had 2.6 times the risk of newly diagnosed COPD, after adjusting for smoking[3]. Among 71,531 nurses followed for 16 years, reported in the American Journal of Clinical Nutrition, COPD risk rose with cured-meat intake and reached 1.5 times at four or more servings a week[4].

These are observational studies, and smoking remains the dominant cause of COPD. The link with cured meat held after researchers took smoking into account[3], in men and in women.

Asthma

The French E3N cohort has followed about 5,700 women since 1993[5]. In a 2022 analysis in Nutrients, healthier plant-based eating came with fewer new asthma symptoms[5], and unhealthful plant-based eating came with more[5]. Much of the effect ran through body weight, which means part of the benefit comes from the lower weight that tends to go with a healthy plant-based diet[5].

A 2020 position paper in Nutrition Reviews concluded that plant-centred eating appears to protect against asthma and ease its symptoms, by way of lower inflammation, less oxidation and changes in gut bacteria[6]. The authors recommend more fruit and vegetables and less saturated fat and dairy[6].

Across COPD and asthma, the same pattern repeats: whole plant foods on one side[1][2][5][6], processed meat and a junk version of plant eating on the other[1][3][4][5], and the lungs doing better with the first[1][2][3][4][5][6].