Besides lowering the risk of cancer and coronary heart disease due to high levels of vitamin C and beta carotene which are important antioxidants, broccoli also appears to benefit people suffering from chronic obstructive pulmonary disease (COPD).

COPD is often caused by smoking and is the fourth-leading cause of death in the United States, affecting more than 16 million people. The disease is characterized by emphysema and chronic bronchitis, which obstructs air flow to the lungs. There is no cure for this deadly disease and the current drugs do not slow its progression.

How exactly broccoli helps in COPD? Well, Shyam Biswal, an associate professor in the department of environmental health sciences and the division of pulmonary and critical care medicine at Johns Hopkins School of Medicine, and colleagues found that the levels of a specific protein found in the lung called NRF 2 which defends the lung against inflammation-related injury are very low in people suffering from COPD. A compound in broccoli called sulforaphane could stabilize these levels of NRF2.

For the study, the researchers analyzed tissue samples from the lungs of smokers and former smokers with or without COPD. When compared with healthy lung tissue, COPD lung tissue showed marked decline in the activity and concentrations of NRF2-dependent, inflammation-fighting antioxidants. There were also low levels of DJ-1, a biochemical regulator in the lung which stabilizes the levels of NRF2.

Sulforapane has been showed to be able to restore antioxidant gene expression in human epithelial tissue in which DJ-1 has been reduced.

“NRF2-dependent antioxidants and DJ-1 expression was negatively associated with severity of COPD. Therapy directed toward enhancing NRF2-regulated antioxidants may be a novel strategy for attenuating the effects of oxidative stress in the pathogenesis of COPD,” Biswal said.

The study will be published in the Sept. 15 issue of the American Journal of Respiratory and Critical Care Medicine.