Waistline part inheritance, part choice

What you inherit from your parents can come as just as much of a surprise to your waistline. But it doesn’t have to!

After analyzing data on more than 100,000 children from six countries, including the United States, scientists found that as a kid you inherit about 20 percent of your body mass index from your mom and 20 percent from your dad.

But 60 percent of your childhood and teenage weight is determined by lifestyle choices. Though many overweight and obese adolescents become obese adults, genetics is not destiny when it comes to weight.

Mom and Dad: Help your children achieve a healthy weight by preparing shared family meals, introducing fresh food choices, especially vegetable dishes (even frozen), discouraging fast food and sweet sodas, and enjoying walks, hikes, ballgames and bike rides together.

Teens: You have a lot of control over your lifestyle choices. You can decide to opt for a normal weight — and a brighter future — by saying no thanks to unhealthy food choices at home, school and out with friends. And join intramural, club or schoolbased sports teams for a stronger body and happier attitude. SMOKING WHILE PREGNANT

When you smoke while pregnant — or inhale second- or even third-hand smoke residue — your fetus is shortchanged on placenta-derived oxygen while still ingesting many toxic chemicals.

The result? Poisoning your soon-to-be can cause premature birth or even infant death, and in a newborn it can trigger a rash of developmental problems.

But wait, there’s more: Recent laboratory tests reveal that nicotine directly damages the fetal development of auditory nerve signaling.

Hearing impairment can lead to deficits in language and learning. Other studies have linked smoking while pregnant with mental illness in offspring.

So if you smoke and you’re pregnant (or even thinking about getting pregnant), join a quitsmoking support group. Nicotine patches and other replacement therapies aren’t a good option while you’re pregnant; you’re still delivering nicotine to the fetus. Your best choice? Cold turkey. And guess what?

That can work, according to a study of pregnant women in the Annals of Internal Medicine. If you’re not pregnant though, it’s not the most effective way to knock it off. Email questions for Mehmet Oz and Mike Roizen to youdocsdaily@sharecare.com.