Here is the big problem – soda has displaced milk. Calcium deficiency is not likely to be a frequent problem until school age. It is well known that breast milk and cow’s milk formulas are both good food sources. Unless the source is not available, or there is an absorption or allergy problem, we should not worry about our normal children until they enter the “pop” age. Sodas can displace milk intake at far too early an age. Many teenagers and young parents may think of milk as being the stuff for little kids and may substitute juice or water for milk if they are convinced that soda is bad.
Adolescence is the time to build bones. The issue of calcium intake is something very important to think about, especially for girls in their teens. This is the time when the good bones of women in their forties and fifties are being predetermined. For a growing child over five years old, recommendations vary from 800-1,200 mg of calcium per day.
Dairy products are still a good calcium source, and cultured dairy is especially good. For example, 1.5 ounces of hard cheese provides 300 mg of calcium, the same as 8 ounces of milk or yogurt. Cultured milk products, such as buttermilk and yogurt, have many health advantages. And low-fat yogurt (low- not non-, since some fat is needed for the good bacteria to feast on) weights in at 415 mg per 8 ounces (over a third better than plain milk). Another ready source is 300 mg of any common calcium-based (usually calcium carbonate) antacid. If the daily recommendation is not met by the end of the day, take a tablet containing 300 mg after dinner. When the diet is heavy in acid-forming meat and other protein sources and light in alkaline-forming fruits and vegetables, more calcium is used to neutralize urine and lost from the body, leaving less for bone metabolism. Along with adequate vitamin D and exercise, calcium issued more efficiently and not as much is needed.
Other sources do not come up to the level of milk products, but coupled with other lifestyle factors they may prove adequate. These are: sardines (91 mg in two little ones, soft bones and all), sunflower seeds (4 ounces contains 33 mg of calcium but a whopping 100 mg of magnesium, half the daily requirement), and leafy green vegetables (10 ounces of raw spinach contains 202 mg calcium and half a cup of boiled has 139 mg but is relatively heavy in magnesium at 65 mg). Peanuts and dried beans offer much less calcium but are a moderately good source of magnesium. Soybeans deserve a special dispensation in that, depending on how they are prepared, they are relatively abundant in both calcium and magnesium. A half-cup of raw, firm tofu yields 258 mg of calcium and 118 mg of magnesium. A half-cup of dry roasted soybeans yields 232 mg of calcium and 196 mg of magnesium, which meets the daily requirement. Other sources of calcium and magnesium include almonds, whole grains, and figs. (We have given magnesium values at the same time as those for calcium because magnesium is required to aid the metabolism of calcium).