Calcium is a nutrient required by all living organisms, including humans. It is the most plentiful mineral in the body and is essential for bone health.

Humans require calcium to build and maintain strong bones, and the bones and teeth are the body’s 99% Trusted Source of calcium. It is also required for the brain and other parts of the body to communicate properly. It helps with muscle movement and cardiovascular function.

Calcium occurs naturally in many foods and is added to some products by food manufacturers. There are also supplements available.

People require vitamin D in addition to calcium because it aids the body’s absorption of calcium. Vitamin D is obtained from fish oil, fortified dairy products, and sun exposure.

This article discusses why the body requires calcium, which foods contain calcium, what happens if the body does not have enough, and the benefits and drawbacks of taking supplements.

Calcium serves several functions in the body. These are some examples:

Health of the bones

The bones and teeth contain approximately 99% of the calcium in the human body. Calcium is required for bone development, growth, and maintenance.

Calcium aids in the development of children’s bones as they grow. Calcium continues to help maintain bones and slow bone density loss after a person stops growing, which is a natural part of the ageing process.

Females who have already gone through menopause are more likely to lose bone density than men or younger people. They are more likely to develop osteoporosis, and a doctor may advise them to take calcium supplements.

Learn more about osteoporosis here.

Muscle tenseness

Calcium aids in the regulation of muscle contraction. The body releases calcium when a nerve stimulates a muscle. Calcium aids the proteins in muscle in their contraction work.

When the body removes calcium from the muscle, the muscle relaxes.

The circulatory system

Calcium is essential for blood clotting. Clotting is a complicated process with several steps. These contain a variety of chemicals, including calcium.

The role of calcium in muscle function includes maintaining the action of the heart muscle. The smooth muscle that surrounds blood vessels is relaxed by calcium. Several studies have suggested a link between high calcium consumption and lower blood pressure.

Vitamin D is also necessary for bone health and aids in calcium absorption. Learn more about vitamin D and why we require it.

Other responsibilities

Many enzymes require calcium as a cofactor. Some key enzymes cannot function properly without calcium.

According to research, getting enough calcium can lead to:

a lower risk of developing high blood pressure conditions during pregnancy

lower blood pressure in adolescents

lower blood pressure in those whose mothers ate enough calcium while pregnant

increased cholesterol levels

colorectal adenomas, a type of non-cancerous tumour, are less likely
Learn more about the consequences of low calcium levels.

Visit our dedicated hub for more in-depth resources on vitamins, minerals, and supplements.

Foods high in calcium

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

The following are excellent resources:

Reliable Source:



dairy alternatives fortified with vitamins, such as soy milk

salmon and sardines



Many fortified breakfast cereals contain green leafy vegetables such as broccoli, turnip leaves, watercress, and kale.

fruit juices fortified

nuts and seeds, particularly almonds, sesame seeds, and chia seeds

grains and legumes

cornmeal, as well as corn tortillas

Calcium is found in some dark green vegetables, such as spinach. They do, however, have high levels of oxalic acid. According to studies, oxalic acid reduces the body’s ability to absorb calcium.

Find out how to get enough calcium on a plant-based diet by clicking here.

How much money do I require?

People require the following amounts of calcium, according to the Office of Dietary SupplementsTrusted Source (ODS):

200 milligrammes for ages 0-6 months (mg)

260 mg for 7-12 months

700 mg for ages 1-3 years

ages 4 to 8: 1,000 mg

9–18 years old: 1,300 mg

1,000 mg: 19-50 years

Males 51-70 years: 1,000 mg, females 1,200 mg.

1,200 mg for people aged 71 and up

Women who are pregnant or breastfeeding require 1,000-1,300 mg per day, depending on their age.

A doctor may advise you to take extra calcium if you:

have begun menopause

Menstruation may be stopped due to anorexia nervosa or excessive exercise.

are lactose intolerant or allergic to cow’s milk

adopt a vegan diet

a lack of calcium

Low calcium levels, also known as hypocalcemia, can be caused by the following conditions or lifestyle habits:

Bulimia, anorexia, and a variety of other eating disorders

mercury poisoning

Magnesium overconsumption

Laxative use on a long-term basis

Prolonged use of certain medications, such as chemotherapy or corticosteroid chelation therapy, used to treat metal toxicity

parathyroid hormone deficiency

Calcium may be excreted by people who consume a lot of protein or sodium.
a few cancers

excessive caffeine, soda, or alcohol consumption

Celiac disease, inflammatory bowel disease, Crohn’s disease, and other digestive diseases are examples of such conditions.

some surgical procedures, such as stomach removal

kidney disease


a lack of vitamin D

a lack of phosphate

Some calcium is excreted by the body through sweat, urine, and faeces. Foods and activities that promote these functions may lower calcium levels in the body.

Calcium supplementation

Calcium supplements may be recommended by a doctor for people who are calcium deficient.

Calcium supplement users should do the following:

Check with their doctor first to see if they require supplements.

follow the doctor’s advice on dosage

Take the supplement with food for maximum absorption and to reduce the risk of side effects.

Take the supplements at regular intervals, usually two or three times per day.
According to the ODS, approximately 43% of all adults in the United States, including 70% of older females, take calcium supplements. Taking calcium supplements can increase daily calcium intake by about 300 mg per day on average.

Many calcium supplements contain vitamin D as well. Vitamin D promotes protein synthesis in the body and aids in calcium absorption. Magnesium also helps to strengthen bones, and calcium supplements may contain magnesium as well.

Supplement Types

There are various types of supplements. A doctor can advise you on the best course of action. This will be determined by the individual’s needs and preferences, as well as any medical conditions and medications they are taking.

Although elemental calcium is the pure mineral, calcium in its natural state exists in conjunction with other compounds.

Calcium compounds and elemental calcium may be present in varying proportions in supplements. As an example:

Calcium carbonate is made up of 40% elemental calcium. This type is widely available, as well as reasonably priced and convenient. It should be taken with food because stomach acid aids in absorption.

This calcium lactate contains 13% elemental calcium.

Calcium gluconate has a calcium content of 9%.

Calcium citrate has a 21% elemental calcium content. It can be taken with or without food. It can help with inflammatory bowel disease, achlorhydria, and some absorption issues.

Supplemental dangers

According to research, there is conflicting evidence regarding the benefits and drawbacks of supplement use.

The majority of experts

Trusted Source agree that it is preferable to obtain nutrients from natural food sources, though this is not always possible.

However, some studies have suggested that calcium supplementation may be harmful.

Adverse effects

When taking calcium supplements, some people experience gastrointestinal symptoms such as bloating, constipation, gas, or a combination of all three.

Calcium citrate typically has fewer and milder side effects than calcium carbonate. Taking the supplements with food or spreading them out throughout the day may help reduce the frequency or severity of side effects.


Calcium levels that are extremely high can result in:

kidney issues

soft tissue and blood vessel calcification

stones in the kidneys


Although high calcium levels from taking too many supplements may cause these severe side effects, the ODS believes they are more likely the result of cancer and thyroid issues.

Complications that could occur

Previous research has raised concerns that taking calcium supplements may increase the risk of osteoporosis.

dependable source of:

stones in the kidneys

a decrease in iron absorption

a greater risk of having a heart attack

Recent research, however, suggests that these fears may be unfounded.

Some drugs may interact with calcium. The following recommendations are made by experts:

Calcium supplements should be taken separately from some antibiotics.
When taking calcium channel blockers, a common type of blood pressure medication, avoid taking supplements.
Calcium is required for the formation and maintenance of healthy bones and teeth. It may also help manage blood pressure, among other things.

Calcium is best obtained through dietary sources such as dairy products, green leafy vegetables, and tofu. However, for some people, a doctor may advise supplementation.

Calcium supplementation is not recommended for everyone due to individual differences in requirements. Anyone thinking about taking supplements should consult with their doctor first.

Calcium supplements can be purchased online.

The last medical review was on January 28, 2020.

Orthopedics / BonesNutrition / DietCat 1minerals 4 sources