A study by Singh V et al showed that yoga breathing had positive effects in 18 patients with mild asthma. Participants were asked to breath using a machine that slowed their breathing similar to that achieved in pranayama yoga or to placebo device. This study demonstrated an improvement in the measured breathing parameters of all patients. It also showed a statistically significant increase in the dose of histamine needed to cause a 20% reduction in average forced expiratory volume in 1 s (FEV1 which is the maximum amount of air you can forcefully exhale in one second) during pranayam (but not in placebo device), demonstrating a tendency towards reduction in allergic asthma symptoms. (7)
Caffeine and Asthma:
Caffeine at a dose of 7 mg/kg was reported to improve lung function in a study that included 10 individuals with bronchial asthma. Patients were given placebo and caffeine (3.5 mg/kg and 7 mg/kg ) two hours prior to exercise and a lung function test (spirometry) was administered an hour and two hours after and at 5, 15, and 30 minutes post exercise. Forced expiratory volume (FEV1), a measure of lung function, improved significantly and stopped constriction of the airways in the lungs caused by exercise. (8)
