PHILADELPHIA (WPVI) -- The kids are going back to school, and that means it's time to start packing their lunch once more.
Most parents only think of the nutrition.
But before you start shopping, a Philadelphia dentist has some advice.
She says some popular lunchbox snacks we think are healthier can actually play havoc on kids' teeth.
7-year-old Miles Pham is generally a healthy lunch eater, eating lots of vegetables and fruit.
"He loves apples. During apple season, he'll have 2 apples a day if you let him," says his mom, Victoria.
Dr. Shireen Malik, of Nicholas Cosmetic Dental Center in Center City, says parents usually think sugar is the big cavity-maker.
While applesauce is a kids' favorite, it's very high in added sugar.
But starchy, processed carbs, such as chips and pretzels are as bad - or worse - than candy, because they stick to teeth.
"I see kids coming in for cleaning, and there's chips stuck on their teeth," says Dr. Malik.
Those carbs make the mouth acidic, becoming food for bacteria that causes tooth decay.
"Once the acid hits the tooth, it starts to demineralize," she notes.
Dr. Malik says better snack choices include cheese cubes or string cheese, unsalted nuts, and fresh fruit and berries, like strawberries, which help rinse the teeth.
Carrots and celery are popular with kids - and can help undo some effects of the sugar and carbs.
"If you put a little fibrous stuff in the lunch box, that helps stimulate saliva, and saliva actually has calcium, and it supplies that to your teeth. And that protects them from cavities," she said.
And water, whether from the tap or bottle, is also a meal-time cavity preventer.
She urges kids to briefly swish their mouth after eating.
"Even if they rinse with regular water. Just this act of rinsing can get them out of a lot of trouble," she says.
Victoria's uncle was a dentist, so she's passed along his tooth care lessons to Miles.
But she also feels lucky her son never got a taste for junk food.
"He just doesn't like it. Yeah, and I'm happy with that," she says.
Dr. Malik says if you've got to eat sweets, eat a little regular chocolate.
Our saliva washes it off the teeth faster.
Packing school lunch? Dentist reveals worst choices for kids' teeth