What is calcium?

Calcium is one of the best known minerals in nutrition, yet many people only have a surface understanding of what it actually is and how it supports the body. Most commonly associated with strong bones and teeth, calcium plays a far wider role in maintaining normal health and bodily function.

In this article, we explain what calcium is, how it works in the body and why maintaining a healthy intake through diet or supplements matters.

Is calcium a mineral?

Yes. Calcium is a mineral, which means it’s an inorganic element that the body cannot produce on its own and must obtain from food or supplements.¹ Minerals are essential for life because they help the body to carry out vital functions such as building tissues, supporting nerve and muscle activity and keeping fluids balanced.¹ 

Most of the calcium in the body is stored in the bones. This storage serves both structural roles and acts as a reserve to support other functions when dietary intake is low. 

Because the body cannot make calcium itself, regular intake is important. Good dietary sources include dairy products, leafy greens, fortified plant milks, almonds and fish such as sardines where the bones are eaten. 

If you don’t get enough calcium, your body will use what’s stored in your bones – and over time, this can affect your bone strength, making fractures and other injuries more likely.

What does calcium do for the body?

Calcium has more roles in the body than many people realise. Beyond supporting healthy bones and teeth, it contributes to a range of normal, everyday physiological processes that many people take for granted.

Regulates blood clotting

Calcium helps your blood to clot normally when you get a cut or injury. This is the process your body uses to stop bleeding. When bleeding starts, your body quickly works to form a clot, and calcium plays an important role in helping this happen properly.² 

Without enough calcium, the efficiency of this response may be affected – which means it might take longer for your blood to clot when you’re injured. Fortunately, most people can get enough calcium through a healthy, balanced diet. 

Supports metabolism and digestion

Calcium contributes to a normal energy-yielding metabolism, meaning it helps the enzymes involved in breaking down your food and releasing energy.³ It also supports digestion by helping to activate digestive enzymes, which are responsible for breaking down carbohydrates, proteins and fats into smaller units that your body can absorb.

By supporting the actions of these enzymes, calcium helps your body to get the most out of the food you eat. In real life, this means your body can better absorb and use important nutrients like vitamins and minerals, which support your energy levels, digestion and overall wellbeing.

Maintains muscle and nerve function

Calcium supports normal muscle function and nerve transmission, essentially helping your body to move and process information effectively. 

Every time a muscle contracts, calcium is involved in initiating the movement.⁴ Whether your heart is beating or you’re lifting a cup, calcium helps to ensure that your muscles respond when they should.

Calcium also contributes to normal neurotransmission – the way nerves communicate with each other and with muscles. It triggers the release of neurotransmitters, which are chemical messengers that allow signals to pass between cells. 

If calcium levels fall too low over a prolonged period, you may experience muscle cramps or abnormal nerve sensations, which is why it’s vital to maintain a healthy intake. 

Contributes to cell specialisation

Calcium also plays a role in cell division and specialisation, which refers to how cells grow and develop specific functions.

Throughout life, your body constantly replaces and repairs tissues, and calcium helps guide these processes. In simple terms, it supports your body in building and maintaining healthy cells.

If calcium levels are too low, these processes may not work as efficiently. Over time, this can affect how well tissues repair themselves and may contribute to issues with overall cell function. While this isn’t something you can easily see day to day, it plays an important role in keeping your organs and tissues working properly.

Forms healthy bones and teeth

Perhaps the most widely recognised role of calcium is in forming and maintaining healthy bones and teeth. Bones are living tissues that are constantly being broken down and rebuilt without you even noticing. Calcium helps to give them strength and structure, so they stay strong and resilient over time.¹

Getting enough calcium during childhood and adolescence supports the development of strong bones early in life. However, calcium remains just as important in adulthood, as it helps to maintain bone density and supports long term skeletal health.

Your teeth also rely on calcium to stay strong. It helps to maintain their hardness and protects them from everyday wear.

If you do not get enough calcium, bones can gradually become weaker and more fragile over time. In everyday terms, this may increase the risk of fractures as you get older. Teeth can also be affected, potentially becoming more sensitive or more prone to issues such as decay.

For those looking for targeted support, a product such as Nutraxin’s Bone Formula Calcium Magnesium Plus Collagen is designed to complement a balanced diet and help to maintain bone health.

Why balanced intake matters

Most people can get enough calcium through a varied diet, but certain groups may need to pay more attention. For example, people who follow a plant-based diet or don’t eat dairy often need to focus more on calcium-rich foods or consider supplementation under professional guidance.

In the United Kingdom, adult calcium intake recommendations are generally around 700 mg per day, though individual needs may vary depending on age and life stage.⁵ Speaking to a healthcare professional before starting any supplement is a sensible step to ensure recommendations match your personal requirements.

Getting the right amount of calcium as part of a healthy lifestyle can help to support not only your bones and teeth, but also everyday processes including muscle function, nerve support and metabolism.

References

1. NHS. (2021). Calcium. https://www.nhs.uk/conditions/vitamins-and-minerals/calcium/
2. European Food Safety Authority (EFSA). (2014). Scientific opinion on dietary reference values for calcium. https://www.efsa.europa.eu/en/efsajournal/pub/1665
3. National Institutes of Health, Office of Dietary Supplements. (2023). Calcium – Fact Sheet for Health Professionals. https://ods.od.nih.gov/factsheets/Calcium-HealthProfessional/
4. Harvard T.H. Chan School of Public Health. (n.d.). Calcium and health. https://www.hsph.harvard.edu/nutritionsource/calcium/
5. British Dietetic Association. (2025). Calcium. https://www.bda.uk.com/resource/calcium.html