Last revised on December 18, 2012
By Claire McCarthy, M.D.
Boston Children's Hospital
We all know that secondhand smoke is bad for us; we hear it all the time. But I'm not sure that everyone realizes just how bad it is and that it doesn't take much exposure to do damage.
Take, for example, a study that looked at how secondhand smoke affects the hearts of children.
Researchers in Finland followed 500 children ages 8 through 13. Every year they tested the children's blood to measure their exposure to tobacco smoke in the previous few days. The researchers also used ultrasound to measure the thickness and health of the children's arteries.
By age 13, healthy children who were exposed to secondhand tobacco smoke had thickening of the major arteries. They also had higher levels of apolipoprotein B. This blood protein is a direct measure of the type of lipoproteins that can cause heart disease. These effects were greatest in children with the most exposure to tobacco smoke, but were present even in children with modest exposure.
This is pretty amazing. It means that if your 13-year-old has been exposed on any regular basis to tobacco smoke, he could already have heart disease!
Here are some other facts parents need to know:
- Every year, secondhand smoke causes between 150,000 and 300,000 lung infections in children younger than 18 months. This leads to between 7,500 and 15,000 hospitalizations.
- Children with asthma who are exposed to cigarette smoke have more frequent and severe asthma attacks. (Exposure to cigarette smoke can make it more likely that a child will have asthma in the first place.)
- Children living with smokers can have slower lung growth.
- Secondhand smoke is responsible for more than 750,000 middle ear infections in children every year.
- Exposure to cigarette smoke increases the risk that a baby will die of sudden infant death syndrome (SIDS).
- Rolling the windows down in the car when someone is smoking doesn't make it safe. A study in New Zealand showed that even with the windows down, the amount of smoke in the car was equivalent to being in a smoky bar! Some states have banned smoking in the car when there are passengers younger than 17.
- Exposure to the actual smoke is the most dangerous. But more research is suggesting that the particles that get into things like hair, clothing and furniture (the particles that make people smell like cigarette smoke) are toxic as well. This means that smoking outside may not be enough to keep others safe.
In fact, there is no safe level of exposure to secondhand smoke.
To keep children as safe as possible, here's what parents need to do:
- If you smoke, stop. Your children's lives may depend on it. And you want to grow old enough to see your grandchildren, don't you? Quitting isn't easy, but there are treatments that can help. Talk to your doctor.
- Don't ever let anyone smoke around your child. It's okay to be rude. Blame it on your doctor if you like. You can say something such as, "I'm sorry, but our pediatrician says we can never let Junior be exposed to cigarette smoke."
- Boycott the houses of people who smoke. This may upset certain friends and relatives. But what's more important your child's health or being polite? And who knows, when those friends and relatives realize you're serious, it may just be the push they need to quit.
- Do everything you can to keep your child away from tobacco smoke. Before you say yes to a playdate, ask if there are any smokers in the house; if there are, have it at your house instead. Don't go to restaurants that have smoking areas; avoid smoking areas in public places.
- Support smoke-free policies in your community. Going to work or to a public place shouldn't mean putting your health at risk!
- Talk to your children about the dangers of smoking. All your work to keep them away from secondhand smoke will be for nothing if they start smoking themselves! Make sure they know that smoking is a really bad idea. (This will be more difficult if you smoke!)
If we work together, we can help our children and all of us breathe easier and live longer, healthier lives.
Back to top
Claire McCarthy, M.D., is an assistant professor in pediatrics at Harvard Medical School, an attending physician at Children's Hospital of Boston, and medical director of the Martha Eliot Health Center, a neighborhood health service of Children's Hospital. She is a senior medical editor for Harvard Health Publications.