Calcium is the most abundant mineral in the human body, with 99% of it stored in our bones and teeth. The remaining 1% plays a crucial role in various cellular functions. Calcium is a critical component of a healthy diet, and our body tightly regulates calcium levels in the blood through hormonal pathways.

Functions of Calcium

  • Bone health: Calcium is a primary component of bones and teeth, providing strength and structural support.
  • Muscle function: Calcium plays a critical role in muscle contraction, including skeletal, smooth, and cardiac muscles.
  • Nerve function: Calcium is essential for nerve impulse transmission, allowing cells to communicate effectively.
  • Blood clotting: Calcium is involved in blood coagulation, helping to prevent excessive bleeding in case of injury.
  • Enzyme activation: Calcium is a cofactor for various enzymes, participating in numerous biochemical reactions.

Good Sources of Calcium

  • Dairy products: Milk, yogurt, and cheese are rich sources of calcium.
  • Leafy green vegetables: Kale, spinach, collard greens, and pak choi (Chinese cabbage) contain substantial amounts of calcium.
  • Fish: Sardines and salmon, especially when eaten with bones, are good sources of calcium.
  • Nuts and seeds: Almonds, sesame seeds, and chia seeds are calcium-rich options.
  • Fortified foods: Calcium-fortified foods such as orange juice, cereals, and plant-based milk are widely available.

How Much Calcium Do We Need? 

 (Based on NIH recommendations): The recommended daily allowance (RDA) for calcium varies depending on age, sex, and life stage. Some general guidelines are:

  • Infants 0-6 months*: 200 mg/day (Milligram)
  • Infants 7-12 months*: 260 mg/day
  • Children 1-3 years: 700 mg/day
  • Children 4-8 years: 1,000 mg/day
  • Children 9-13 years: 1,300 mg/day
  • Adolescents 14-18 years: 1,300 mg/day
  • Adults 19-50 years: 1,000 mg/day
  • Adults 51-70 years (males): 1,000 mg/day
  • Adults 51-70 years (females): 1,200 mg/day
  • Pregnant and breastfeeding women: 1000 mg/day
  • Adults 71 years and older: 1,200 mg/day

(*) Adequate intake (AI)

What Are The Signs of Calcium Deficiency?

 Calcium deficiency, or hypocalcaemia, can manifest in various ways. Some common signs and symptoms include:

  • Muscle cramps and spasms
  • Numbness or tingling in extremities
  • Weak or brittle nails
  • Dental problems, such as tooth decay and gum disease
  • Osteoporosis or osteopenia, characterised by low bone density

What Happens If I Take Too Much Calcium?

Excessive calcium intake, or hypercalcemia, can lead to several health issues, such as:

  • Kidney stones: High calcium levels can lead to the formation of calcium-based kidney stones.
  • Impaired kidney function: Excess calcium can cause calcification in the kidneys, affecting their ability to filter waste.
  • Heart problems: Elevated calcium levels can lead to calcification in blood vessels and heart valves, increasing the risk of cardiovascular diseases.
  • Constipation and gastrointestinal issues: Excess calcium can cause digestive problems such as constipation, bloating, and gas.
  • Interference with nutrient absorption: High calcium levels can interfere with the absorption of other minerals, such as iron, zinc, and magnesium.