In the United States there has been a dramatic increase in the number of people who are obese and in the number of people who have asthma. Both are considered serious public health concerns. Several studies have shown that becoming obese or overweight can increase the risk of developing asthma or can make asthma symptoms more severe and difficult to control. How obesity affects asthma is not fully understood. This research study will examine whether obesity affects the amount of inflammation that is present in the lungs of people with asthma, and will also examine whether obesity leads to narrow and stiff airways.

Participation in this study involves 2 visits in order to complete questionnaires, various pulmonary function tests, as well as the collection of blood, urine, and exhaled breath condensate specimens.

This research study includes optional genetic and bronchoscopy substudies.

Inclusion Criteria:

• Adults 18 to 70 years of age
• If asthmatic, currently taking a short acting beta agonist and an inhaled corticosteroid
• Never smoked or limited smoking history

Exclusion Criteria:

• Current upper respiratory illness (other than asthma)
• Illegal drug use within past month
• Consumption of more than 6 alcoholic drinks per week
• Active, pronounced rhinitis or sinusitis
• Pregnancy
• Currently taking oral steroids or steroid injection over the past month
• Asthma exacerbation over the past month
• Certain medical illnesses

Asthmatics and healthy volunteers