All You Need To Know About Calcium Deficiency

Did you know that 1 to 2% of our body weight is calcium? Calcium is considered the 5th major essential element in the human body, and it is also the 5th common element in the earth. What makes calcium important is that 99% of it is located in bone and teeth. Calcium is responsible for maintaining healthy bone and teeth, but not just that. It’s also responsible for neurotransmissions in the nervous system, muscle contraction and to stimulate secretions from glands.

So, what will happen if calcium levels drop? Obviously, symptoms of calcium deficiency will be centered on bone and teeth, as 99% of it is distributed in them. Also, deficient levels of calcium in the body give rise to a life-threatening condition called tetany. Tetany is a disease characterized by muscle spasms which may affect any muscle group in the body. The affected muscle groups differ according to how low is the calcium levels in the blood. Muscle spasms may affect the breathing muscles, including the diaphragm, which may lead to death.

Why calcium and what’s its benefits?

• Bone and teeth health

40% of the bone composition is made up of calcium. Calcium is the mineral that gives the bone its hard consistency. Without calcium, the bone would become weak and fragile; this condition is called osteoporosis in adults and rickets in children. In the case of teeth, calcium promotes dental health. Some calcium is stored in teeth to strengthen and protect them from tooth decay.

• Muscle contraction and nerve signal transmission

Muscle fibers need nerve impulses to take action. Calcium is important for muscles and nerves as it works on the contraction and relaxation of muscle fibers, and delivers the chemical transmitters from the nerve endings to the muscles.

• Helps with weight loss

Studies show that people who increase calcium intake in their diet lose fat quickly, especially from their belly region.

• Protect against cancer

It is considered anticarcinogenic, and calcium is also responsible for cell grow, maturation, proliferation and to regulate both cell differentiation and programmed cell death (Apoptosis).

• Lowers blood pressure

As calcium helps in muscle contraction, it helps to dilate the blood vessels. Blood vessel dilatation is one of the body mechanisms to decrease blood pressure. Calcium controls contraction and relaxation of the heart muscle, which reduces the heart rate and the blood pressure.

• Decreases premenstrual syndrome (PMS)

Research shows that calcium helps relieve premenstrual symptoms such as bloating, mood swings, cramps and headaches as it controls muscle contractions and nerve functions.

• Protects against bleeding disorders

Calcium helps with blood clotting during injuries and prevents excessive bleeding. It is essential to stimulate clotting enzymes as they work after binding to the calcium.

• Improves digestion

Calcium is used as an antacid to help with acid reflux and heartburn. It also improves digestion, as it stimulates the muscles of the digestive system.

Where can I get calcium from?

Calcium can be found in a lot of food, especially animal sources such as dairy milk, yogurt, cheeses, egg whites, canned salmon and sardines, trout and clams. You can also find this mineral in plant sources like soy milk, tofu, spinach, black-eyed peas, okra, acorn squash, bak choy, dried figs, apricots, almonds, sesame seeds, and tahini.

Here are some of the highest calcium sources and the amount of calcium in 100 grams of each source:

  • Cheese: 1184 mg, 91% of daily calcium intake
  • Tofu: 683 mg, 53% of daily calcium intake
  • Yogurt: 199 mg, 15% of daily calcium intake
  • Milk: 122 mg, 9% of daily calcium intake
  • Spinach: 136 mg, 10% of daily calcium intake
  • Clams: 92 mg, 7% of daily calcium intake
  • Trout: 86 mg, 7% of daily calcium intake

How do our bodies absorb calcium?

Our bodies absorb calcium differently according to age, sex, and body needs. 60% of calcium intake is absorbed in infants and children as they need more calcium to build their bodies. In adults, the body only absorbs 20% of calcium intake as their body doesn’t grow as much as children, and this percentage decreases with age.

Multiple factors affect calcium absorption as:

Vitamin D

It plays a significant role in calcium absorption, as it encourages intestinal cells to absorb more calcium. Vitamin D affects calcium deposition in bones. Thus, the levels of the vitamin should be normal to protect against or treat calcium deficiency. Sun is a natural source of vitamin D, especially midday, and that will help with elevating vitamin D levels, which will increase calcium absorption.

○ Magnesium

Magnesium also helps in calcium absorption and deposition in bone. The body needs 310 mg daily from magnesium.

○ Coffee and tea

Avoid drinking coffee and tea after meals as they contain tannic acid. Tannic acid combines with calcium, forming a complex which interfere with calcium absorption.

○ Plant-based food

Calcium intake can be found in plants, as in beans, nuts, and seeds. They contain phytic acid and oxalic acid, which interfere with calcium absorption.


Supplements and food rich in iron should be taken separately from food rich in calcium because they are absorbed from the same cells. Thus, consuming them together will create competition between iron and calcium, which decreases both of their absorptions.

○ Digestive system

The digestive system is responsible for nutrient absorption. Gut health should be monitored so the body can benefit from the ingested food. Any GIT diseases may affect the absorption of calcium.

○ Parathyroid gland

It secretes a hormone called parathyroid hormone (PTH) with a similar action than vitamin D on the absorption of calcium. The parathyroid hormone decreases the excretion of calcium in the urine and its absorption in the intestine, and increases calcium mobilization in bone tissue. If levels of parathyroid hormone increase, this will lead to calcium deficiency.

How much calcium do I need daily?

Daily recommendations of calcium differ according to age, sex, daily activity, the individual’s health, metabolic and medical conditions. But, the recommended calcium amount according to the World Health Organization (WHO) is:

  • From birth to 6 months: 1000 mg
  • Infants from 7 to 12 months: 1500 mg
  • Children from 1 to 3 years: 500 mg
  • Children from 4 to 8 years: 700 mg
  • Children from 9 to 13 years: 1000 mg
  • Teens from 14 to 18 years: 1300 mg
  • Male adult from 19 to 70 years: 1000 mg
  • Female adult from 19 to 50 years: 1000 mg
  • Pregnant teens and women: 1100 mg
  • Breastfeeding teens and women: 1300 mg
  • Seniors from 50 years and older: 1300 mg

Calcium should be combined with vitamin D as the calcium can’t deposit in bone or absorbed from the gut with vitamin D.

People at risk of calcium deficiency may need more than the daily calcium recommendation.

Who is at risk of calcium deficiency?


Pregnancy and breastfeeding women are at risk because the nutritional demand of the infant increases calcium requirement, and may cause calcium deficiency when this is not being prevented with supplements or by increasing calcium intake in food.

◘ Women

5% of bone mass decreases after the 1st year of menopause. This happens because of reduced estrogen levels. This will increase calcium loss in urine and reduce its absorption.

◘ Vegan and vegetarians

Plant-based diets are structured around plants that contain low levels of calcium. Leafy greens and vegetable as beans, nuts, and seeds contain oxalic acid and phytic acid which bind to calcium and prevent its absorption.

◘ Infant and children

Infants and children experience a growth surge, so the body requirements for all the elements and minerals increase. This growth surge put infant and children under the risk of developing calcium deficiency.

◘ High coffee and tea in diet

Coffee and tea contain a tannic acid that combined with calcium forming a complex which interfere with calcium absorption.

What are the causes of calcium deficiency?

• Low calcium intake

A low calcium diet or a plant-based diet, because plant products have less calcium and oxalic and more phytic acids that combine with calcium and decrease its absorption.

• Poor calcium absorption

Digestive system diseases that decrease calcium absorption as in Crohn’s and celiac diseases.

• Para-follicular cell cancer

The thyroid gland contains cells called parafollicular cells responsible for the secretion of calcitonin hormone. Calcitonin increases calcium excretion in the urine. In cases of cancer, calcitonin levels exceed their normal levels, leading to calcium deficiency.

• Vitamin D and parathyroid hormone deficiency

Decrease vitamin D and parathyroid hormone levels lead to decreased calcium absorption from the intestine and affect bone health.

• Medications

Some medications as cortisone interfere with calcium absorption or increase its secretion in urine.

When do you consider calcium deficiency?

Calcium is one of the body minerals with a narrow range of normal levels. A subtle increase or decrease affects the body massively. Calcium blood tests measure both ionized calcium (free calcium) and non-ionized calcium (bound to protein). Normal calcium levels range from 8.5 to 10.5 mg/dl.

Low calcium levels show two types of tetany:

  • Latent tetany: 7.5 to 8.5 mg/dl
  • Manifested tetany: below 7.5 mg/dl.

How do you know that you have calcium deficiency and when you need to seek professional advice?

♦ Getting sick or infected easily and often

Calcium is responsible for a healthy and robust immune system to fight against bacteria and viruses. So, if you are getting sick easily, you may need to check your calcium level in the blood.

♦ Excessive fatigue and tiredness

Low calcium levels affect muscle contraction and transmission of nerve impulses, leading to tiredness and chronic fatigue.

♦ Bone, back pain and frequent bone fractures

Calcium deficiency
Osteoporosis, Calcium deficiency

Calcium maintains a healthy bone, as it is the main mineral in bone composition. So, bone ache and back pain may be considered a sign that you have a calcium deficiency. Calcium deficiency decreases bone density, which leads to thinning, brittle bone, or osteoporosis in adults, and all of them are considered risk factors for bone fracture. Calcium deficiency in children causes a condition called rickets, which is a bone disease characterized by weak and soft bone, delayed growth and bone deformities.

♦ Brittle nails, frizzy and damaged hair

Calcium is a part of hair and nail composition. Any decrease in calcium level will affect both of them, leading to nails that are easily broken and damaged hair.

♦ A numbing sensation in hands and fingers

This happens because calcium is responsible for nerve signal transmission. Fewer signals and delayed transmission leads to this numbing sensation.

♦ Depression, low concentration

They may happen with very low calcium levels, as this mineral is responsible for signal transmission in the brain.

♦ Bleeding disorders

Calcium helps with blood clotting as it is a part of the clotting system that activated after injuries which prevent excessive bleeding, it also stimulating clotting enzymes. In calcium deficiency, it will increase the clotting and bleeding time leading to bleeding disorders.

♦ Tetany

It is a symptom caused by calcium deficiency, which is characterized by muscle spasms. It’s a life-threatening condition if not appropriately treated.

How do we maintain healthy levels of calcium and prevent calcium deficiency?

– Eat food that rich in calcium such as dairy milk, yogurt, cheeses, egg whites, canned salmon and sardines, trout and clams, soy milk, tofu, spinach, black-eyed peas, okra, acorn squash, bak choy, dried figs, apricots, almonds, sesame seeds, and tahini.

– Treat and prevent vitamin D deficiency by daily exposure to the sun, especially during midday for 10 to 30 mins, maintain healthy body weight with outdoor walk or jogging to get your daily exercise and sun exposure.

– Treat your medical condition that affects calcium metabolism.

– Use calcium supplements, especially with people how are at risk of calcium deficiency as pregnant and breastfeeding women.

– Talk to your doctor if you have a family history of osteoporosis.

– Avoid drinking coffee and tea after meals.

How can you treat a calcium deficiency?

– You should elevate calcium levels in the blood by working on the same points as in the prevention of calcium deficiency. You can ask your doctor, as he may recommend calcium supplements to increase its levels. Calcium supplements are available over the counter, and for most adults the recommended daily allowance is 1000 mg. You should ask your doctor beforehand.

– In the case of manifested tetany, the patient should be taken to the hospital as it a life-threatening condition and should not be treated at home.

Calcium supplements may cause bloating, which can be treated by drinking a lot of water.

osteoporosis, Calcium deficiency