Positive Health Online

Abstract

COHEN and colleagues, Pediatric Ambulatory Clinic, Rabin Medical Center, Petach Tiqva, Israel sought to discover whether vitamin C has a protective effect upon the hyperreactive airways of people with exercise-induced asthma (EIA).

Background

Methodology

20 asthma patients ( 13 males; 7 females) aged 7-28 years participated in the study. All patients underwent pulmonary function tests at rest, prior to and 1 hour following 2 g oral vitamin C. They were then randomly assigned, double-blind, to receive 2 g vitamin C or a placebo 1 hour prior to a 7-minute exercise session on a treadmill. Pulmonary functions tests were conducted following an 8-minute rest. This sequence was repeated 1 week later, with each patient receiving the other treatment (vitamin C or placebo). Patients were advised to stop using their regular asthma medication or bronchodilatory 12 hours prior to the test.

Results

All 20 patients were diagnosed with EIA, which is defined as a decline of at least 15% in their forced expiratory volume in 1 second following a standard exercise test on a motorised treadmill. Vitamin C did not affect the pulmonary function test results at rest after 1 hour. However, in 9 patients, a protective effect upon exercise-induced hyperreactive airways was documented with vitamin C. 4 out of 5 patients receiving vitamin C and who documented a protective effect upon EIA were given 0.5 g/day vitamin C for 2 additional weeks, with the same protective effect.

Conclusion

Although vitamin C may not be able to prevent EIA, vitamin C may have a protective effect upon airway hyperreactivity in certain patients with EIA.

References

Cohen HA et al. Blocking effect of vitamin C in exercise-induced asthma. Arch Pediatr Adolesc Med 151(4): 367-70. Apr 1997.

Comment

It is interesting yet self-evident that the two most prevalently researched options in the treatment of asthma are: 1) nutritional, with supplementation with vitamins, minerals and essential fatty acids; and 2) changes in breathing pattern, the latter either through relaxation, hypnosis, yoga, autogenic or biofeedback. The above research updates illustrate both these approaches. Cohen et al, by working with exercise-induced asthma, combines indirectly the nutritional approach with the effects of exercise and therefore the breath. Asthma is such a huge problem, affecting such a significant minority of all children in the developed world, that all avenues of exploration need to be pursued.