SPECIFIC AIM The aim of this study is to determine if increasing calcium intake to recommended levels with dairy foods in adolescent females with habitually low calcium intake and above-the-median body mass index (BMI) for sex and age will decrease body fat gain compared to similar females who continue their low calcium intake. .

HYPOTHESIS Post-menarcheal adolescent girls with habitually low calcium intake who consume dairy foods providing at least 1200 mg of calcium per day will have a smaller increase in percent body fat, as measured by dual energy absorptiometry, during one year than post-menarcheal adolescent girls on a usual diet of 600 mg of calcium per day or less.

Inclusion Criteria:

• Age 13-14 years old (must be this age when consent is signed)
• Above the 50th percentile for BMI
• Above the 85th percentile for BMI with approval from their primary physician
• At least one and one- half years post menarche
• Habitual dietary calcium intake of 600mg/d or less as assessed by 3 day diet diary. This will be inclusive of supplemental calcium and dietary intake.
• Willingness to increase dietary calcium (low fat [skim, 1%, 2%] milk or yogurt) for one year

Exclusion Criteria:

• Menarche prior to age 10
• History of lactose intolerance or milk allergy
• Weight >300 pounds
• BMI > 97 percentile for age and gender
• Pregnancy
• Chronic disease or disorder like diabetes, polycystic ovarian syndrome, thyroid disease, seizures or cancer (cancer is ok if it has been >10 years)
• Use of steroids like prednisone, prednisolone, hydrocortisone, Flovent, Advair, or Nasonex
• Use of weight reducing medications like Meredia, alli, Dexatrim or Xenical
• Use of contraceptives like Yasmin, Ortho Tri-Cyclen, Apri, Aviane or Depo-Provera for any reason, including acne (see inclusive list)
• Use of acne medications like Accutane or high dose Vitamin A
• Use of ADHD medications like Adderall, Ritalin, Concerta. (Per Dr. Ramaswamy-Straterra OK) (see inclusive list)
• Use of seizure medications like Lamictal or Phenobarb (see inclusive list)
• Use of anti-depressants like Prozac or Effexor (see inclusive list)
• Diagnosed eating disorder
• Dieting behavior with weight loss > 10 pounds in the last 3 months (IF YES, consult with Project Manager)
• Metal in the skeleton (pins, rods, etc)
• Sibling of a child who is or has been on a dietary study in the last 5 years
• Total body BMC Z-score below -2.0 at baseline
• Participating in other ongoing research protocols