Meer groenten en fruit voor goede longfuncties.*

Uit een kleine studie onder jongeren (17-21 jaar) blijkt dat meer groenten en fruit duidelijk zorgt voor betere longfuncties. Het zijn vooral de vitamine C uit fruit, bètacaroteen uit groenten en magnesium uit noten en donkere groenten, die hiervoor verantwoordelijk zijn.

Diet Rich In Vitamin C Linked To Better Lung Function

Earlier studies have suggested that individuals who consume fewer fruits and vegetables, and therefore fewer antioxidants such as vitamins C, E and beta-carotene, are at higher risk of developing asthma symptoms or reduced lung function.
Vitamin C is found in all fruits and vegetables and is in high concentrations in green peppers, oranges and other citrus fruits and juices, tomatoes, papaya and watermelon.
In the first study to look at this relationship in a healthy, well-nourished population of young adults, Ira B. Tager and colleagues from the University of California at Berkeley and San Francisco studied the effect of diet on lung function in 243 first-year college students.
These students completed a food frequency questionnaire, provided a sample of their DNA and participated in a test of lung function.
The researchers focused on measures that reflect the function of the smaller airways of the lung due to their importance in asthma, ozone-induced airway damage, and cigarette smoke-induced chronic obstructive lung disease.
Building on this hypothesis, researchers from the University of California at Berkeley evaluated whether lung function is associated with dietary antioxidant intake and the glutathione S-transferase (GSTM1) polymorphism. The GSTM1-null genotype is highly prevalent and is associated with deficits in lung function in children.
In all, 243 healthy adults aged 17–21 years who had never smoked underwent comprehensive assessment. Results of multivariate regression analysis revealed that intake of vitamin C and magnesium – and fruit for male students – were consistently and positively associated with lung function.
Among female participants, those in the highest quintile of vitamin C intake had a 0.48 l/s increase in forced expiratory flow after 75% of expelled volume (FEF>75%), a 0.41 l/s increase in forced mid-expiratory flow (FEF25–75%), and a 0.54 l/s increase in FEF25–75%/forced vital capacity ratio compared with those in the lowest quintile.
For males, eating more fruit was associated with a marginal increase in forced expiratory volume in one second. Additionally, magnesium intake appeared to benefit males with the GSTM1 genotype, although the authors warn that this observation should be interpreted with caution.
Writing in the European Respiratory Journal, J Tujague and co-authors say their findings add to the growing evidence of an association between vitamin C intake and lung function in healthy female adolescents.
“The current study does not support a role for the GSTM1-null genotype as an independent risk factor for decrements in lung function,” they say.
They found that vitamin C intake from foods was associated with higher lung function, especially among female students.
Magnesium, a trace mineral found in peanuts, beans, and dark green leafy vegetables, was also strongly associated with lung function in males and to a lesser extent in females.
This report adds to a growing body of research suggesting that dietary antioxidants play an important role in protecting respiratory health.
Title of the original article:
Antioxidant intake, GSTM1 polymorphism and pulmonary function in healthy young adults (Januari 2006)