New studies find 70 percent of American kids aren't getting enough vitamin D. Are yours?

Health.com reports that 70 percent of American kids aren't getting enough vitamin D, and such youngsters tend to have higher blood pressure and lower levels of good cholesterol than their peers, according to two new studies published this week in the journal Pediatrics. Low vitamin D levels also may increase a child's risk of developing heart disease later in life, experts say.

Because so many kids spend more time on the computer than in the sun, they're not getting enough vitamin D from good ol' Mother Nature. Plus, even when they're outside, they're slathered in sunscreen, which blocks the good effects of sun as well as the bad.

Although formula is fortified with vitamin D, breast milk is often vitamin D deficient, so breastfed babies are particularly at risk.

What can moms do?

Give kids supplements. Babies need 400 units (in liquid form), and kids also need 400 units daily. If you're breastfeeding, you need to take a supplement, too -- 1,000 units are recommended.

Catch some rays. Doctors recommend that adults and kids go in the sun unprotected for 5-10 minutes two times a week to get vitamin D. After those 5-10 minutes, go back inside or slather on the sunscreen.

Stock up on juice and milk. Encourage kids to drink juice or milk fortified with vitamin D.

Serve foods with vitamin D. Cod liver oil is the best source of vitamin D, but who's eating that? More palatable foods that include the vital vitamin include: tuna fish, salmon, fortified cereals, eggs, and cheese.

Do you or your kids take a vitamin D supplement?