Calcium: Health benefits, foods, and deficiency


Calcium is a nutrient that all living organisms, including humans, need. It is the most abundant mineral in the body and is vital for bone health.

This article will examine what calcium is, why the body needs it, the possible causes of a deficiency, and foods rich in calcium.


What is calcium?

What is calcium

Humans need calcium to build and maintain strong bones, and 99% of our calcium is found in bones and teeth.

This mineral is also necessary to maintain good communication between the brain and other parts of the body.

It also plays a role in muscle movement and cardiovascular function.

Calcium needs vitamin D3 to be fixed in the bones. We find vitamin D in fish oil, whole dairy products and egg yolk. It is synthesized naturally in the body when exposed to the sun.


Why do we need calcium?

For bone health

For bone health

In the human body, about 99% of calcium is found in bones and teeth. Calcium is essential for the development, growth and maintenance of bones.

As children grow older, calcium contributes to the development of their bones.

After growth, calcium continues to strengthen bones and slow down bone density, a natural phenomenon associated with ageing.

Postmenopausal women are more likely to lose bone density than young women and men. They, therefore, have a higher risk of developing osteoporosis and may be recommended for a calcium supplement.


For muscle contraction

Calcium participates in the regulation of muscle contraction. When a nerve stimulates a muscle, the body releases calcium. Calcium helps muscle proteins to perform the work of contraction.

When the body pumps calcium out of the muscle, the muscle relaxes.


For the health of the cardiovascular system

Calcium plays a crucial role in blood clotting. The coagulation process is complex and involves several steps. These involve many reactions where calcium plays a significant role.

The role of calcium in muscle function includes maintaining the action of the heart muscle. Calcium relaxes the smooth muscle that surrounds the blood vessels. There is also a link between high calcium consumption and a drop in blood pressure.


Other roles of calcium

Calcium is a co-factor of many enzymes. Without calcium, some key enzymes cannot function effectively.

A sufficient amount of calcium promotes:

  • Lower risk of developing blood pressure problems during pregnancy.
  • The drop in blood pressure in young people.
  • The drop in blood pressure in women whose mothers have consumed enough calcium during pregnancy.
  • An improvement in cholesterol values
  • Lower risk of colorectal adenomas, a type of non-cancerous tumour.


Calcium deficiency, what causes?

The following living conditions or habits can lead to low levels of calcium or hypocalcemia:

  • Bulimia, anorexia and other eating disorders.
  • Mercury exposure.
  • Overconsumption of magnesium.
  • Prolonged use of laxatives.
  • Prolonged use of certain medications such as chemotherapy or corticosteroids.
  • Chelation is used for exposure to metals.
  • Absence of parathyroid hormone.
  • People who use a lot of Protein or sodium can excrete calcium.
  • Some cancers
  • High consumption of caffeine, soda or alcohol.
  • Certain conditions such as celiac disease, inflammatory bowel disease, Crohn’s disease and other digestive diseases.
  • Some surgical procedures including the removal of the stomach.
  • Renal failure.
  • Pancreatitis.
  • Vitamin D deficiency.
  • Phosphate deficiency.
  • The body removes a little calcium in sweat, urine and faeces. Foods and activities that encourage these functions can reduce calcium levels in the body.


Foods rich in calcium

Foods rich in calcium

Calcium can be obtained from a range of foods and beverages.

Here are some excellent sources:

  • Yoghurt
  • Milk
  • Fortified milk substitutes such as soy milk
  • Sardines and salmon
  • Cheese
  • Tofu
  • Green leafy vegetables such as broccoli, turnip leaves, watercress and kale.
  • Fortified breakfast cereals
  • Enriched fruit juices
  • Nuts and seeds, especially almonds, sesame and chia
  • Legumes and cereals

NB: Some dark green vegetables, such as spinach, contain calcium. However, they also have high levels of oxalic acid. Oxalic acid reduces the body’s ability to absorb calcium, according to some studies.


Chemistry of Calcium (ca):

atomic number20
atomic weight40.078
melting point842 °C (1,548 °F)
boiling point1,484 °C (2,703 °F)
specific gravity1.55 (20 °C, or 68 °F)
oxidation state+2
electron configuration1s22s22p63s23p64s2


To conclude

Calcium is an essential mineral for building and maintaining strong bones and teeth. In addition to its many roles necessary for a healthy body, it can also help lower blood pressure.

It is possible to obtain enough calcium from food sources such as dairy products, green leafy vegetables or tofu. However, supplementation may be helpful in case of proven impairment or regular sports practice.