Effects of Secondhand Smoke on Children, by Age

If you smoke, or someone at home does, you have probably wondered exactly what the air in your house does to your kids. The effects of secondhand smoke on children are better documented than most parents realize, and they are different at different ages. This guide goes stage by stage, from babies to teenagers, using what the CDC, the NHS, and the American Academy of Pediatrics say, and it ends with the steps that make the most difference.

Effects of Secondhand Smoke on Children: At a Glance

The CDC states that there is no safe level of exposure to secondhand smoke and that even brief exposure can cause immediate harm. Here is how the main effects line up across three major health sources.

Babies: SIDS and Breathing

Infants are the group with the most to lose. The CDC says infants exposed to secondhand smoke after birth are more likely to die from sudden infant death syndrome. It explains that chemicals in secondhand smoke appear to affect the brain in ways that interfere with its regulation of infants’ breathing.

The American Academy of Pediatrics agrees that infants have a higher risk of SIDS if they are exposed. Your baby’s doctor can talk through the other safe-sleep steps with you, and the conversation doesn’t have to be a lecture. If you’re trying to quit, say so at the next visit.

Toddlers and School-Age Children: Ears, Chests and Asthma

Once children are older, the effects show up in the things parents deal with all the time. The CDC says children exposed to secondhand smoke are at an increased risk for acute respiratory infections, middle ear disease, more frequent and severe asthma, respiratory symptoms, and slowed lung growth. It also says children whose parents smoke around them get more ear infections, and that wheezing, coughing, and shortness of breath are more common in exposed children.

The NHS adds chest infections, meningitis, and coughs and colds to the list of things that are more likely in children who live with a smoker. The AAP also links secondhand smoke to tooth decay in children.

If your child has asthma, this matters even more. The CDC says secondhand smoke can trigger an asthma attack in a child, and the AAP says children with asthma may have more severe attacks when they are exposed. Tell your child’s doctor about any smoke exposure at home, including from relatives or caregivers. If your child has frequent ear infections, chest infections or wheezing, tell the doctor about that too.

Teenagers

Most of the guidance above is written about “children” without splitting out teenagers, so it’s reasonable to assume the respiratory risks don’t simply vanish at 13. What we can say from CDC survey data is that teenagers are exposed too: in the 2013-2014 survey discussed below, about a third of nonsmoking adolescents aged 12 to 19 were exposed. Teens are also old enough to tell you what bothers them, so ask them. And if your teen vapes or smokes, our guide to helping your teenager quit vaping can help.

Why Children Are More Vulnerable

The NHS says passive smoking is especially harmful for children because they have less-well-developed airways, lungs and immune systems. The AAP makes the same point, noting that children’s lungs are still developing. Children also usually have no say in the matter. They can’t open a window, leave the car, or ask a guest to step outside.

How Many Children Are Exposed?

A CDC report on nonsmokers in the United States found that during 2013-2014, one in four nonsmokers, including 14 million children, were exposed to secondhand smoke. In that survey, 37.9% of children aged 3 to 11 and 32.0% of adolescents aged 12 to 19 were exposed. These figures are from 2013-2014, so they are older than we would like, and they show how many children were affected rather than how many are today. For a closer look at how passive exposure compares with active smoking, see is secondhand smoke worse than smoking.

What to Tell Your Child’s Doctor

Doctors can only help with what they know about. Telling them about smoke at home isn’t a confession; it is useful medical information, and it may change how they look at a cough that won’t clear up. Before the next appointment, it can help to write down:

• who smokes or vapes around your child, and where that happens (at home, in the car, at a grandparent’s house, in child care);
• how many ear infections, chest infections or episodes of wheezing your child has had in the past year;
• whether symptoms seem to get worse after time in a particular place;
• what you have already changed at home, and what you are still working on.

If you smoke, it is fine to say you would like help to stop. Your child’s doctor may be able to point you to support, or you can raise it with your own doctor. If your child has trouble breathing, get urgent medical care right away rather than waiting for a routine visit.

What Makes the Biggest Difference

The AAP says quitting is the best way to prevent your children from being exposed to secondhand smoke. If you are not there yet, these steps still matter:

• Make your home smoke-free. The NHS says that opening windows and doors or smoking in another room does not protect people.
• Keep your car smoke-free. The NHS says children are particularly vulnerable in the family car, where secondhand smoke can reach hazardous levels even with the windows open. Some places have laws on this too, covered in our guide to smoking in a car with children.
• Choose smoke-free care. The AAP suggests choosing a smoke-free babysitter and encouraging tobacco-free child care and schools.
• Don’t assume outside solves it. The AAP says children whose parents smoke only outside are still exposed to the chemicals in secondhand smoke, and advises against smoking near your children, even outdoors.
• Be ready for awkward conversations. Decide what you’ll say to relatives before the next visit. If you are dealing with smoke coming from another household, see secondhand smoke from neighbors.

Frequently Asked Questions