Given that all human organs have vitamin D recep-tors, it is not surprising that vitamin D3 de ciency can also cause disease symptoms in the lungs. Known diseases include productive and obstructive bronchitis, asthma, chronic obstructive pulmonary disease (COPD), and frequent respiratory infections [1, 2]. To date, there is insu cient data to support whether vitamin D replacementimproves these pul-monary diseases [3].  erefore, our center began measuring vitamin D3 levels in patients with pulmonary diseases and replacement was initiated where levels were low. Results in two patients are discussed below