Calcium And Phosphorus Faqs

Patient Education

What is calcium?

Calcium is a mineral essential for healthy bones and teeth in the human body. It is the fifth most required element by the human body after oxygen, carbon, hydrogen, and nitrogen. Ninety-nine percent of the calcium in the body is stored in the bones, the remaining 1% is in teeth.

What are the functions of calcium?

Calcium salts provide rigidity to the skeleton. Calcium phosphate is a major component of the bones and gives strength to bones. Calcium is also important for the proper functioning of the nerves and muscles and helps in clotting or blood whenever there is a wound. Calcium plays a vital role in normal hormonal functions. It also aids in cell signaling pathways, which help in cell to cell communication[1].

How does calcium act in the body?

Calcium is absorbed in the small intestine. Phytates present in the husks of many kinds of cereal as well as in nuts, seeds, and legumes, can form insoluble calcium phytate salts in the gastrointestinal tract and prevent absorption of calcium. Similarly, excess oxalates can precipitate calcium in the bowel. Vitamin D and parathyroid hormone increase the absorption of calcium from the gut. Vitamin D stimulates the bone forming cells leading to mineralisation of bones and parathyroid hormone helps to mobilise the calcium from the bones, thus increasing the calcium level in the blood. On the other hand, a hormone called calcitonin helps to decrease the calcium level in the blood and aids its deposition on bones.[1]

Which foods are rich in calcium?

Excellent sources of calcium include dairy products, spinach, turnip greens, mustard greens, and collard greens. Milk and juices fortified with calcium are also good sources of calcium. Egg is a very good calcium source. Cereals, which are the staple foods in India, contain only a small proportion of calcium.[1]

What is the daily requirement of calcium for a normal individual?

The recommended daily requirement of calcium is 210-800 mg/day for children up to 8 years of age and 1300 mg/day for older children.

What happens if calcium is deficient in the diet?

Deficiency of calcium can lead to weaker bones, seizures and abnormal positions of the hands and feet called tetany. Deficiency can occur due to poor intake, due to poor absorption, vitamin D deficiency, parathyroid hormone deficiency and chronic kidney disease. Long term deficiency can lead to osteoporosis.

What happens if overdose of calcium occurs?

Toxicity from calcium is not common because the gastrointestinal tract normally limits the amount of calcium absorbed. Therefore, short-term intake of large amounts of calcium does not generally produce any ill effects aside from constipation and an increased risk of kidney stones. Long term use of a high dose of calcium along with a high dose of vitamin D can lead to deposition of calcium in other tissues of the body and increased blood calcium levels that can disturb the rhythm of the heart.

What is phosphorus?

Phosphorus is an important mineral along with calcium required for the human body to maintain healthy bones. It is present as calcium phosphate in the bones. It is present in the body in the form of phosphates (PO4). It forms calcium phosphate with calcium and forms the skeleton of the bones. Bone contains about 85% of the body's phosphate. The rest is located primarily inside cells.

What are the functions of phosphorus?

Apart from maintaining healthy bones, phosphorus is important for energy utilization in the body.

Phosphorus also forms an important part of the genetic material i.e RNA and DNA. It also helps maintain the pH of blood. Phosphorus is also necessary for the formation of some proteins and lipids.[1]

How does phosphorus act in the body?

Phosphate absorption from the intestines is enhanced by vitamin D. Parathyroid hormone decreases the absorption of phosphorus from the intestine and increases its loss in the urine.

Which foods are rich in phosphorus?

Foods rich in phosphates are all-bran cereal, almonds, cashew nuts, cheese, dried fruit, egg, garlic, legumes, lentils, meat, milk, peanuts, sesame seeds, sunflower seeds, whole wheat bread and yogurt.

What is the daily requirement of phosphorus for a normal individual?

The daily requirement of phosphorus is 100-500 mg/day in children less than 8 years of age and 1250 mg per day for older children.

What happens if phosphorus is deficient in the diet?

Low blood phosphorus can occur with burns, defective absorption from the gut, poor intake, use of aluminum-containing antacids, and long term use of diuretic drugs. Patients present with seizures, muscle weakness, and low hemoglobin. Chronic deficiency can lead to weak bones.

What happens if overdose of phosphorus occurs?

Like calcium, short term high intake of phosphorus does not lead to any side effects. However long term high intake and intake of phosphorus-rich food in patients with chronic kidney disease can lead to seizures and lower blood calcium levels.