Improving pulmonary function in newborns.
500 mg of daily vitamin C given to pregnant smoking women “decreased the effects of in-utero nicotine” and “improved measures of pulmonary function” in their newborns, according to a study by Cindy T. McEvoy and others at the Oregon Health and Science University in Portland, published in a recent issue of the Journal of the American Medical Association (JAMA).
Researchers have long known that smoking during pregnancy can harm the respiratory health of newborns. Maternal smoking during pregnancy can interfere with normal lung development, resulting in lifelong increases in asthma risk and other pulmonary complications. The researchers note that “more than 50% of smokers who become pregnant continue to smoke, corresponding to 12% of all pregnancies.” That adds up to a lot of newborns each year who will start off with more wheezing, respiratory infections, and childhood asthma than their counterparts born to non-smoking mothers.
McEvoy and her colleagues wanted to find out whether a daily dose of vitamin C would improve the results of pulmonary function tests in newborns exposed to tobacco in utero.
It did. In an accompanying editorial, Graham L. Hall calls the randomized, double-blind, placebo-controlled clinical trial “well-conceived and executed…. Lung function during the first week of life was statistically significantly better (by approximately 10%) among infants born to mothers randomized to receive Vitamin C compared with infants born to mothers randomized to received placebo.” Moreover, the prevalence of wheezing in the first year was reduced from 40% in the placebo group to 21% in the Vitamin C group.
The decreases in asthma and wheezing in the Vitamin C newborns were documented through the first year of life.
A 10% reduction does not sound like a lot, but, as Hall writes, “small population-level changes in lung function may lead to significant public health benefits, and the improvements in lung function reported here could be associated with future benefit.”
In their paper, the researchers conclude: “Vitamin C supplementation in pregnant smokers may be an inexpensive and simple approach (with continued smoking cessation counseling) to decrease some of the effects of smoking in pregnancy on newborn pulmonary function and ultimately infant respiratory morbidities, but further study is required.”
Pregnant women should not smoke, and quitting is by far the healthiest option. As Hall writes: “By preventing her developing fetus and newborn infant from becoming exposed to tobacco smoke, a pregnant woman can do more for the respiratory health and overall health of her child than any amount of vitamin C may be able to accomplish.”
McEvoy C.T., Nakia Clay, Keith Jackson, Mitzi D. Go, Patricia Spitale, Carol Bunten, Maria Leiva, David Gonzales, Julie Hollister-Smith & Manuel Durand & (2014). Vitamin C Supplementation for Pregnant Smoking Women and Pulmonary Function in Their Newborn Infants, JAMA, 311 (20) 2074. DOI: http://dx.doi.org/10.1001/jama.2014.5217
Graphics Credit: http://www.quitguide.com/
