A Mediterranean-style diet may reduce the risk of chronic obstructive pulmonary disease (COPD) by 50 per cent, says new research from Harvard.

The British Medical Journal Thorax reported that the antioxidants and polyphenols, found in cereals, wine, fruits, nuts, legumes and whole grains, fish and olive oil appear to offer protection.

The large prospective cohort study used data from the Health Professionals Follow-up Study and compared the relative risk of COPD amongst men consuming a Mediterranean-style diet to those with a Western-style diet, rich in refined grains, cured and red meats, fries and desserts.

Researchers at Thorax used dietary data on 42,917 men, age range of 40-75, collected using a 131-item food frequency questionnaire. Over 12 years of follow-up, 111 self-reported cases of newly diagnosed COPD were identified.

The Mediterranean diet has been linked to longer life, less heart disease, and protection against some cancers. The diet's main nutritional components include beta-carotene, vitamin C, tocopherols, polyphenols, and essential minerals.

They also noted that the high glycaemic load of the Western diet has also been linked to impaired lung function.