The Role of Calcium
Calcium is a mineral. Compared to other minerals, calcium is the most abundant in the human body, with an amount of about 1200 grams. Of this, 99% forms bones and teeth, while 1% is present in the blood and soft tissues. Therefore, the role of calcium is like the body's scaffolding. In addition, calcium is required for blood clotting, activating some enzymes in the body, regulating heart and nerve activity, and maintaining muscle tension.
Who is at risk for calcium deficiency
The populations most at risk for calcium deficiency include pregnant and lactating women, children, and the elderly.
Starting from the fourth month of pregnancy, the fetus requires more calcium. If a pregnant woman does not pay attention to her calcium intake or supplementation, she may lose about 8-10% of her bone calcium.
Children and adolescents in their growth and development period have a relatively high demand for calcium. When calcium intake is insufficient to meet their growth needs, calcium deficiency can occur. In infants and young children, calcium deficiency is often accompanied by protein and vitamin D deficiency, which can lead to stunted growth, abnormal cartilage structure, poor bone calcification, bone deformities, rickets, poor tooth development, and an increased risk of cavities.
After middle age, the excretion of calcium from bones increases while absorption decreases. In old age, combined with a decline in the body's own metabolic capacity and low gastrointestinal absorption, the calcium intake needs to be higher than that of younger people. Therefore, the elderly need to pay more attention to their calcium intake and supplementation.
Infants under 6 months do not need additional calcium
Some parents fear their children will get rickets and try to give calcium tablets to infants who are only a few months old, which is actually unnecessary. The cause of rickets in children is not just a lack of calcium, but also a deficiency in vitamin D. Vitamin D increases the absorption of calcium and phosphorus in the intestines. When a child lacks vitamin D, it can lead to incomplete bone ossification and a series of rickets symptoms. Breast milk contains comprehensive and well-balanced nutrition, as well as various immune-active substances. Exclusive breastfeeding can meet all the fluid, energy, and nutrient needs of an infant under 6 months. Therefore, full-term, healthy infants do not need additional calcium supplementation in the first six months after birth.
For calcium supplementation, food is the first choice
Influenced by various factors, when people think of calcium supplementation, they immediately think of buying calcium tablets or calcium oral solutions, believing that these products can quickly replenish calcium. In reality, supplementing calcium through diet is an effective, economical, and safe method.
Among common foods, dairy products are the best food source for calcium. Starting from the second trimester of pregnancy, one should drink at least 250 milliliters of milk or an equivalent amount of dairy products daily and supplement with 300 milligrams of calcium, or drink 450-500 milliliters of low-fat milk to meet the body's calcium needs. In addition, seafood, nuts, legumes, and green vegetables are also primary food sources of calcium. On the basis of drinking milk, one can also consume more dishes made with the above ingredients.
Reference values for calcium intake by age group
Calcium content in different foods
How much of a nutrient is appropriate for intake
Dietary Reference Intakes (DRIs): A set of reference values for the average daily intake of nutrients developed to ensure the reasonable intake of nutrients by the human body, avoiding both deficiency and excess, based on the Recommended Dietary Allowance (RDA).
Adequate Intake (AI): The intake of a nutrient by a healthy population obtained through observation or experiment.
Tolerable Upper Intake Level (UL): The highest average daily nutrient intake level that is unlikely to pose a risk of adverse health effects.
Recommended Intake for the Prevention of Non-communicable Chronic Diseases: The daily intake of essential nutrients proposed with the goal of primary prevention of non-communicable chronic diseases.

Pumpkin and Dried Shrimp Soup
Ingredients
400 grams of pumpkin, 20 grams of dried shrimp, appropriate amount of cooking oil, chopped green onions, and broth.
Method
1. Wash the pumpkin and cut it into pieces.
2. Heat oil in a wok, then add the pumpkin pieces and stir-fry briefly.
3. Add chopped green onions and dried shrimp, and stir-fry for a moment longer.
4. Add water and cook into a soup. The pumpkin and soup are now ready to eat.
Nutritional Analysis
Dried shrimp is rich in minerals, especially calcium. However, note that dried shrimp is salty, so the amount of salt used should be reduced accordingly.
Milky Almond Porridge
Ingredients
350 ml fresh milk, 90 grams rice, 35 grams almond slices, 800 ml cold water.
Seasoning
1 small spoonful of rock sugar.
Method
1. Take a pot, add the washed rice and cold water, bring to a boil, then reduce the heat and simmer to make a porridge.
2. Stir in the crushed almond slices and cook for another 5 minutes after it comes back to a boil.
3. Add rock sugar to taste, turn off the heat, and pour in the fresh milk. Mix well and serve.
Nutritional Analysis
Milk is rich in calcium, and almonds are also rich in minerals.
This article is excerpted from "Ma Guansheng Talks About Nutrition" by Ma Guansheng, authorized by Phoenix Hanzhang Books. Reproduction is strictly prohibited.