Children whose parents smoke at home have significantly lower levels of vitamin C in their blood than kids in non-smoking homes, a large study out Monday shows.
The more parents smoke, the less of the vitamin youngsters have in their bloodstreams, says Richard Strauss of the University of Medicine and Dentistry of New Jersey. His report in Pediatrics is the first major scientific study on how passive smoke affects vitamin metabolism in children and adolescents. Passive smoke already has been linked to lower levels of vitamin C in adults.
"Free radicals" in tobacco smoke -- chemicals that damage human cells -- oxidize harmful LDL cholesterol, which can clog arteries and promote heart disease, Strauss says. Vitamin C, an antioxidant, may become depleted from fighting the free radicals in cigarette smoke, he says.
USA Today (Mar 6, 2001), by Marilyn Elias / USA TODAY Page 9D,
by Marilyn Elias,USA Today, Tuesday, 3/6/01
Children whose parents smoke at home have significantly lower levels of vitamin C in their blood than kids in non-smoking homes, a large study out Monday shows.
The more parents smoke, the less of the vitamin youngsters have in their bloodstreams, says Richard Strauss of the University of Medicine and Dentistry of New Jersey. His report in Pediatrics is the first major scientific study on how passive smoke affects vitamin metabolism in children and adolescents. Passive smoke already has been linked to lower levels of vitamin C in adults.
"Free radicals" in tobacco smoke -- chemicals that damage human cells -- oxidize harmful LDL cholesterol, which can clog arteries and promote heart disease, Strauss says. Vitamin C, an antioxidant, may become depleted from fighting the free radicals in cigarette smoke, he says.
Figures show 22% of children and teens are exposed to passive smoke at home.
The new study included 2,968 youngsters ages 4 to 18. Scientists asked parents about their smoking habits, their children's diet and supplemental vitamin use.
Among key points:
Even at the highest levels of depletion, "they're not deficient to the point they'll get scurvy," Strauss says. "We don't know how significant these decreases are or what the long-term effects could be."
But the findings raise potentially serious concerns, says Fima Lifshitz, chief of staff at Miami Children's Hospital and an expert in children's nutrition.
Vitamin C protects not only against heart disease, but also helps prevent DNA changes linked to some cancers, he says. And low vitamin levels could combine with other vulnerabilities to induce illness, Lifshitz says.
Passive smoke has been tied in past scientific studies to higher risk of childhood asthma, ear infections, respiratory illness and sudden infant death syndrome. "Depletion of vitamin C might be related to these problems," he says.
The impact of such vitamin C loss in children merits further study, Lifshitz says. "You just can't ignore less-than-optimal levels of a very important vitamin in kids, especially in view of what we already know about the negative consequences of passive smoke."
The study does not prove smoke causes the vitamin loss, says Vanderbilt University cardiologist Rose Marie Robertson, president of the American Heart Association.
"But when you get these linear relationships, it's stronger scientifically, and to have such measurable cotinine levels in children is a dramatic finding," she says.
Pathology studies show arteriosclerosis begins by adolescence, Robertson adds.
Parents who smoke may be unaware "there are much better things out there now" to get through withdrawal when quitting, such as nicotine patches and gums, she says. "It's easier now than it used to be," Robertson says, "and I hope more parents will try."
Source: Pediatrics 2001;107:540-542.