Inadequate calcium intake can contribute to the development of osteoporosis. If your calcium intake from diet and supplements is not adequate, the body takes what it needs from bone for metabolism.
Recommended calcium intake for adults are as follows:
People ages 25-50 1,000 mg/day
Women on HRT, and men ages 51-64 1,200 mg/day
Women not on HRT, and men ages 51+ 1,500 mg/day
Everyone after age 65 1,500 mg/day
Our peak bone mass is achieved between the ages of 20-30. If calcium intake and/or physical activity is inadequate in childhood and adolescence, we may not build a strong skeleton to help us avoid osteoporosis later in life. Make sure children get enough! Children between ages 1-10 require 800-1200 mg/day. Those aged 11-24 require 1200-1500 mg/day.
An average serving of dairy provides approximately 300 mg. This is a good “ballpark” figure to calculate your dietary intake. A serving is a cup of milk, 8 oz of yogurt, and 1 oz of cheese. Cottage cheese is lower with about 80 mg per 4 oz serving. One cup of ice-cream has about 200 mg of calcium; it is like drinking milk at 300 mg. Vegetables rich in calcium include bok choy (250 mg/cup), broccoli (135 mg.cup), soybeans (175 mg/cup), collard (150 mg/cup), and carrots (100 mg/cup).
Foods high in oxalate and phytate interfere with calcium absorption. Spinich rhubarb, beet greens, and almonds are high in oxalate. Legumes, such as pinto beans, navy beans, and peas are high in phytate, as in wheat bran. Foods that contain phytate or oxalate provide other important nutrients, so they should not be eliminated from your diet. They will not interfere with your calcium nutrition when eaten in moderation or at times when you are not taking calcium.
Diets high in animal protein, sodium, and to a lesser extent caffeine can increase calcium excretion in the urine. The protein and calcium in dairy products do not cancel each other out! The calcium lost due to the protein in dairy product is insignificant. If you are a coffee, tea, or cola drinker, you should increase your calcium intake to offset what is lost.