Childhood Exposure To Second-hand Smoke Has Long-lasting Effects: Fruit Fiber May Help

Individuals 18 or younger, living with one or more smokers, were morethan twice as likely to suffer from chronic dry cough as adults,according to a new study published by researchers at the NationalInstitute of Environmental Health Sciences (NIEHS), a part of theNational Institutes of Health, the University of Minnesota, and theNational University of Singapore. This paper, which appears online inThorax, is the largest study to date on the effects of childhoodexposure to environmental tobacco smoke (ETS) on later respiratorydisease, and the first to include data on dietary intake.

"This research adds to a growing body of evidence that exposure tosecond-hand smoke early in life has health consequences that can last alifetime," said Dr. David Schwartz, Director of the NIEHS. "In additionto finding ways to reduce the exposure of children to tobacco smoke andother environmental pollutants, we also need to look for ways to reducethe disease burden."

The data for this study were collected from the Singapore ChineseHealth Study, a population of men and women of Chinese ethnicityranging in ages from 45 to 74 at enrollment, who live in Singapore. The35,000 non-smokers provided information regarding ETS before and afterage 18, a medical history including information on respiratory symptomsof chronic cough, phlegm production and asthma diagnosis, as well asinformation on dietary intake.

Chronic cough was defined as occurring on most days for at least threemonths of the year and lasting more than two years in a row. More than45 percent of the study participants reported having fathers whosmoked, and 19 percent reported having mothers who smoked. Theresearchers found that more smokers in the home during childhood, waslinked to a greater incidence of chronic cough, and chronic phlegm.

"Because we had previously found in this Singaporean population datasuggesting that a diet high in fruit and soy fiber may reduce theincidence of chronic respiratory symptoms, we decided to study theimpact of fiber on problems associated with early tobacco exposure,"said NIEHS researcher Stephanie London, M.D. "We actually found thatpeople who ate even a small amount of fruit fiber had less chroniccough related to environmental tobacco smoke."

Study participants who ate more than 7.5 grams of fiber each day hadfewer health effects associated with ETS. This is equivalent to eatingabout two apples a day. Dr. London pointed out that the average weightof the Singapore study participants was 127 lbs. She also added thatmost Singaporeans get their fiber from fruits, vegetables and soy.

"Fiber may have beneficial effects on the lung," said Dr. London. "Itseems to have the ability to reduce blood glucose concentrations,reduce inflammation, and enhance antioxidant processes. All of thesemay help to protect the lung against environmental insults, such as ETSin childhood. However, the possible benefits of fiber should not lessenthe importance of reducing exposure to environmental tobacco smoke."

NIEHS, a component of the National Institutes of Health, supportsresearch to understand the effects of the environment on human health.For more information about environmental tobacco smoke and otherenvironmental health topics, please visit our website at http://www.niehs.nih.gov/.