To build strong bones, kids need three things: calcium, vitamin D, and exercise. It's best for kids to get their calcium from food. Because many kids don't get enough vitamin D naturally, it's often best for them to take a supplement.

Calcium: Make sure your child gets enough from foods. Good natural food sources are milk, yogurt, cheese, beans, and some nuts. Some brands of orange juice, breakfast cereal, and other foods have added calcium.

• Babies under 1 year old need 200–260 mg each day, which they easily get from breast milk or formula.
• Kids ages 1–3 years old need 700 mg each day (2–3 servings of calcium-rich foods).
• Kids ages 4–8 years old need 1,000 mg each day (2–3 servings).
• Preteens and teens (9–18 years old) need 1,300 mg each day (4 servings).

Vitamin D (also called vitamin D3): Make sure your child gets enough from foods or a supplement. Good amounts of vitamin D are found naturally in salmon, tuna, liver, eggs, and cod liver oil. Most kids don't eat these foods a lot. That's why food companies add vitamin D to milk, yogurt, baby formula, juice, cereal, and other foods.

• Babies need 400 IU each day. Breast milk is best for babies, but it doesn't have enough vitamin D. So give babies who drink breast milk vitamin D drops or a multivitamin drop that has vitamin D. Formula has vitamin D added. Babies who drink 32 ounces or more of formula each day don't need a vitamin D supplement.
• Kids over 1 year old need 600 IU or more each day. Health care providers often recommend 600 to 1,000 IU daily. Some children need more. Be sure to check with your health care provider about the right amount of vitamin D for your child.

Protect your child's skin with sunscreen, clothing, and shade: Although people get vitamin D when skin is exposed to the sun, there is a risk for skin cancer later in life if your child gets too much sun.

Exercise: Make sure your child gets at least 1 hour of physical activity each day, including weight-bearing exercises:

• Weight-bearing activities that involve walking, running, and jumping are best for building strong bones.
• Low-impact activities like swimming or biking are good exercise and great for overall health, but less helpful for bone health.

• You're not sure how to give your child vitamin D.
• Your child has bone or muscle pain that is new or that gets worse.

What do calcium and vitamin D do? Vitamin D helps the body absorb the two basic building blocks of bone: calcium and phosphorous. Without enough calcium, bones can grow too slowly and become soft, weak, broken, or deformed.

If kids eat healthy foods, do they still need supplements? Kids who eat healthy diets get most of their vitamins naturally, but it's hard to get enough vitamin D through food. That's why kids often need to take a supplement. You can buy vitamin D pills, gummies, chewables, oral drops, and sprays in stores without a prescription. Your health care provider can help you choose the right one for your child.

What else stops kids from getting enough vitamin D or calcium? Some kids have health problems that affect their vitamin D and calcium levels, such as:

• kidney or liver disease
• obesity
• conditions or medicines that prevent the body from absorbing enough vitamin D
• lactose intolerance, milk allergy, or other reasons for not eating dairy foods

How do parents know if kids are getting enough calcium and vitamin D? Health care providers will recommend supplements or diet changes if they think kids aren't getting enough of the vitamins and minerals they need. Usually, they do blood tests only if they think a health problem is stopping a child from getting enough vitamin D or calcium.