QUESTION: My teenage daughter has almost completely quit drinking milk, preferring to drink a soft drink of some kind at meals instead. I'm worried because of all the discussion about osteoporosis and the need for more calcium. Is this a problem for teenagers?

ANSWER: An article in an old Tufts University "Diet & Nutrition Letter" (February, 1987) discussed this topic and suggested that there was a relationship between the amount of milk consumed during adolescence and early adulthood and bone density and the potential for osteoporosis in later years. Since women are more at risk for osteoporosis, it is important that they get enough calcium during these formative years to avoid problems when they get older.They quoted a government study that showed teenagers who drank as little as a third of a can of soda a day were much less likely to get the recommended dietary allowance (RDA) of 1,200 milligrams of calcium than those who drank no soda at all. Even girls who drank no soda received only about 75 percent of the RDA for calcium in this survey.

For those who drank two cans of soda a day, the percent of RDA dropped to 59 percent. Surprisingly, the problem was not as great for teenage boys, who got 90 percent of RDA for calcium even when they drank as much as two cans of pop a day. This result was probably related to the propensity boys have to eat and drink a large amount of everything.

The articles suggested that even though parents have little control over what their children choose as a lunchtime beverage, they should insist that their children drink milk with some of their meals at home. There are also many other sources of calcium (other milk products, dark-green vegetables, dried legumes, etc.) available to young people who resist drinking milk that should be provided to maintain sufficient calcium intake to meet RDA.

- HEALTHFUL LIFESTYLE GOALS: (This is a continuation of the first column in the new year. I promised to give you a few small lifestyle changes each week. If you haven't started, start now!)

Exercise goal: Increase your aerobic exercise (walking, cycling, rowing, etc.) to about 15 minutes a day. Increase the number of abdominal curls to 10. Do them slowly, curling the head and shoulders off the floor and return. Keep your arms by your side.

Diet goal: You should now be drinking 2 percent milk and eating bread without butter. I asked Barbara Higa, a registered dietitian, to help me with the dietary goals and she suggested the next goal be to eat breakfast. She said there are too many people who skip meals, and breakfast is the meal most often skipped. So, your specific challenge is to eat breakfast every morning. Be sure that the main ingredient is cereal and eat one fruit with the cereal. Keep up the good work.

- Garth Fisher is director of the Human Performance Research Center at Brigham Young University.