Anyone experiencing calcium deficiency should consult the doctor. They may order tests and check the levels of calcium in the blood. A person is known to have calcium deficiency when the blood calcium concentrations lie below 8.8 mg/dL. The recommended daily intake of calcium for adults aged 19 to 50 is 1000 mg. Older adults need more calcium intake. Females of age 51 and males of age 71 should consume around 1200 mg of calcium per day.