Calcium is a vital mineral for the human body, playing a potential role in various functions, including bone health, nerve transmission, muscle function, and blood.* Calcium supplements have become increasingly popular, particularly among individuals who may not be getting enough calcium from their diets.

This comprehensive article will discuss the sources of calcium, potential health benefits and risks, and some of the different types of calcium supplements in greater detail.

Recommended amounts

Recommended intakes:

The recommended daily allowance (RDA) for calcium varies depending on age, sex, and life stage. The National Institutes of Health (NIH) provides the following RDAs for calcium:

• Children aged 1-3: 700 mg/day

• Children aged 4-8: 1,000 mg/day

• Children aged 9-18: 1,300 mg/day

• Adults aged 19-50: 1,000 mg/day

• Women aged 51-70: 1,200 mg/day

• Men aged 51-70: 1,000 mg/day

• Adults aged 71 and older: 1,200 mg/day

Pregnant and breastfeeding women should follow the RDA for their age group. It is essential to understand that these recommendations are guidelines, and individual requirements may vary based on factors such as genetics, lifestyle, and specific health conditions. Recommendations might tend to change over time as well.

Sources of calcium

Calcium can be obtained from various food sources, such as dairy products, leafy green vegetables, fish with edible bones, nuts, seeds, and calcium-fortified products. The bioavailability of calcium varies among these sources.

Dairy products, for example, have a higher bioavailability than plant sources. In addition, consuming adequate vitamin D is essential for calcium absorption.

Some examples of calcium-rich, fortified foods include:

• Milk, cheese, and yogurt

• Leafy greens, such as kale, spinach, and collard greens

• Broccoli and bok choy

• Almonds and sesame seeds

• Fish with edible bones, such as sardines and canned salmon

• Calcium-fortified products, including orange juice, tofu, and cereals

It is crucial to incorporate a variety of these foods into your diet to ensure adequate calcium intake and support overall health.

Calcium and bone loss in postmenopausal women

Postmenopausal women might experience a decline in estrogen levels, which may lead to bone loss and have a role in osteoporosis.*

Calcium supplements, along with vitamin D and regular exercise, may help support bone density in this population. Several studies have demonstrated the potential of calcium supplementation in postmenopausal women, showing a change in the number of fractures and potential support for bone mineral density.*

However, it may be important to balance calcium supplementation with other essential nutrients for bone health, such as vitamin D, phosphorus, and magnesium.

Additionally, lifestyle factors like weight-bearing exercises, a balanced diet, and avoiding smoking and excessive alcohol consumption play a crucial role in maintaining bone health in this population.

Calcium and health

Calcium intakes and status:

Calcium status is often assessed through bone mineral density measurements or blood tests for serum calcium levels. Adequate calcium intake is deemed important for supporting bone health, but excessive amount of calcium can lead to adverse effects.* It is crucial to monitor calcium intake and consult with a healthcare professional if you suspect calcium deficiency or excess.

Groups at risk of calcium inadequacy

Certain populations are at a higher risk for calcium inadequacy, including:

• Postmenopausal women

• Vegans or those who avoid dairy products

• Individuals with lactose intolerance

• Individuals with certain medical conditions, such as celiac disease or inflammatory bowel disease

For these populations, calcium supplements may be recommended to help adequate intake levels and supporting bone health.* However, it is crucial to consult with a healthcare professional before starting any supplement regimen.

Calcium supplements may help support metabolic markers

Some research indicates that calcium supplementation may support metabolic markers, such as blood pressure and blood sugar levels.* However, these findings are inconsistent, and further research is needed to determine the long-term effects of calcium supplementation on metabolic health.

Moreover, a balanced diet, regular exercise, and maintaining a healthy weight might be essential for supporting metabolic health and reducing the risk of chronic conditions, such as diabetes and hypertension.*

Who needs to take calcium supplements?

Calcium supplements may be recommended for individuals who:

• Are unable to meet their calcium needs through diet alone

• Have a diagnosed calcium deficiency

• Are at an increased risk of osteoporosis or bone fractures

• Have certain medical conditions that affect calcium absorption

It is important to note that calcium supplementation should be tailored to individual needs and should not be taken without consulting a healthcare professional.

More isn't always better: too much calcium has risks

Excessive dietary calcium intake can lead to several health problems, including:

• Kidney stones*

• Hypercalcemia (high levels of calcium in the blood)*

• Impact on kidney function*

• Calcification of soft tissues, such as blood vessels and heart valves*

It is essential to monitor calcium intake and avoid excessive supplementation to prevent these potential health risks.

Calcium and healthful diets

As explained, a balanced diet that includes a variety of calcium-rich foods is deemed important for supporting bone health and overall well-being.* Consuming adequate amounts of vitamin D, phosphorus, and magnesium is important, as these nutrients play a crucial role in calcium absorption and metabolism.

A well-rounded diet, regular exercise, and a healthy lifestyle will help support overall health.

High levels of calcium in your blood

Hypercalcemia is a condition characterized by high levels of calcium in the blood. It might result from excessive calcium intake, certain medical conditions, or the use of specific medications.

Symptoms of hypercalcemia might include fatigue, muscle weakness, nausea, vomiting, constipation, and confusion. If you suspect hypercalcemia, it is essential to consult a healthcare professional for evaluation and appropriate treatment.

What is the best type of calcium supplement?

There are several types of calcium supplements available, including calcium carbonate, calcium citrate, calcium lactate, and calcium gluconate. You can also find other types of calcium supplement such as calcium AKG. The most common types are calcium carbonate and calcium citrate. Calcium carbonate is typically less expensive and has a higher amount of elemental calcium, but it requires an acidic environment for better absorption.

Calcium citrate is believed to be more easily absorbed and can be taken with or without food, making it an option for individuals with low stomach acid or those taking acid-reducing medications.*

When choosing a calcium supplement, consider factors such as cost, absorption, and potential interactions with medications. 

Calcium supplements might be beneficial for individuals who cannot meet their calcium needs through diet alone or who have specific medical conditions.* However, it is essential to be aware of the potential risks and side effects associated with excessive calcium intake.

It is always best to consult with a healthcare professional before starting any supplement regimen. By maintaining a balanced diet, incorporating a variety of calcium and vitamin-rich foods, and engaging in a healthy lifestyle, individuals can support bone health and overall well-being.*

Calcium chemistry

Calcium is a chemical element with the symbol Ca and atomic number 20. It is an alkaline earth metal, which places it in group 2 of the periodic table. Calcium has a silvery-white appearance, and it is the fifth most abundant element in the Earth's crust.

Chemically, calcium is quite reactive, rapidly forming a dull oxide layer when exposed to air. Calcium also reacts with water, albeit more slowly than its group 2 counterparts, to form calcium hydroxide and hydrogen gas.

Calcium compounds are ubiquitous in nature and have a wide range of applications. Calcium carbonate, for example, is a common component of limestone, marble, and chalk, and is used in the production of cement, as a filler in paper, and as an antacid.

Calcium sulfate, another common calcium compound, is the primary component of gypsum, which is utilized in the construction industry for making plaster and drywall. Calcium phosphate is the principal constituent of hydroxyapatite, the mineral that gives bones and teeth their strength and rigidity.

Calcium biology

In biology, calcium might play a vital role in numerous physiological processes. The most well-known function of calcium is in the formation and maintenance of bones and teeth, where it combines with phosphorus to form hydroxyapatite crystals.

Calcium also serves as an essential signaling molecule within cells. For example, it may help regulate muscle contractions, neurotransmitter release at synapses, and the activation of various enzymes.*

Calcium homeostasis in the body is tightly regulated by a complex interplay of hormones, including parathyroid hormone and calcitonin, as well as vitamin D. These hormones act on the bones, kidneys, and intestines to control calcium absorption, excretion, and bone resorption, supporting that blood calcium levels remain within a narrow range.

Disruptions in calcium homeostasis might lead to various health problems.*

Calcium history

The history of calcium can be traced back to ancient civilizations that utilized a mg of calcium in compounds in various applications. For example, the ancient Egyptians used gypsum to create plaster for construction, while the Romans utilized lime (calcium oxide) in the making of cement. The element calcium itself was not isolated until 1808 when English chemist Sir Humphry Davy used electrolysis to separate calcium from a mixture of lime and mercuric oxide.

Throughout history, the importance of calcium for human health has also been recognized. Ancient Greek physician Hippocrates, for instance, recommended the consumption of calcium-rich foods to support bone health. In the 20th century, as the understanding of calcium's role in the body expanded, the importance of maintaining adequate calcium intake became more evident.

This eventually led to the development of calcium supplements and the fortification of various foods with calcium, helping to address the issue of calcium inadequacy in certain populations.

Today, calcium continues to be an important nutrient for supporting health. As our understanding of calcium's role in the body grows, so does our ability to harness its benefits and develop targeted therapies for various health conditions.

For instance, researchers are actively exploring the potential of calcium-based biomaterials for bone tissue engineering and regenerative medicine. These materials have the potential to revolutionize the treatment of bone injuries and diseases, such as osteoporosis and bone fractures.

Moreover, ongoing research is delving into the complex mechanisms of calcium signaling in cells, which could lead to a better understanding of various diseases and the development of new therapies.

Calcium dysregulation might be implicated in a wide range of pathological conditions, including neurodegenerative disorders and cardiovascular diseases. Unraveling the intricate calcium signaling networks in cells may pave the way for novel treatment strategies targeting these conditions.

Calcium has played a significant role in human history, from its use in ancient construction to its essential function in human biology. As we continue to expand our knowledge of calcium's importance in maintaining health and its involvement in various physiological processes, we are better equipped to address calcium-related health issues and harness its potential in the development of innovative medical treatments.

By incorporating more calcium--rich foods into our diets and staying informed about the latest research on calcium supplementation, we can ensure that we provide our bodies with the necessary building blocks for optimal health and well-being.

Calcium as a trace mineral

While calcium is often thought of as a major mineral due to its significant role in bone health and other physiological processes, it is also present in the body in trace amounts. Trace minerals are essential nutrients required in smaller quantities than major minerals. Although the concentrations of these trace minerals are lower, they still play vital roles in maintaining overall health and well-being.

In the context of calcium as a trace mineral, it is involved in several vital processes at the cellular level. For instance, calcium is a key cofactor for various enzymes, helping to facilitate chemical reactions within cells. Additionally, calcium ions might play a role in blood clotting, as they might help to support proteins that form the clotting cascade*. These trace amounts of calcium, while small, are no less critical for potentially supporting the proper functioning of the body's many systems.*

Calcium for adults

For adults, maintaining an adequate intake of calcium seems important for various aspects of health. Bone health is particularly important during adulthood, as it is the time when peak bone mass is achieved. By ensuring an adequate calcium intake, adults might help support their bone density, which can have long-lasting benefits as they age.* As explained above, in addition to bone health, calcium may play a role in nerve transmission, muscle function, and blood clotting, making it an important nutrient for overall well-being.*

Calcium for aging

As individuals age, the importance of maintaining adequate calcium intake may become increasingly important.* The natural aging process can lead to a decrease in bone density, increasing the risk of fractures and conditions such as osteoporosis. Ensuring sufficient calcium intake, along with vitamin D and regular exercise, might help maintain bone strength and play a role on the risk of age-related bone loss.* You may also want to learn more about strontium.

Calcium and sports - performance

Calcium plays a significant role in the world of sports, with athletes requiring certain calcium levels to help support their peak performance.* One of the essential functions of calcium in the context of sports is its involvement in muscle contractions. Calcium ions are responsible for initiating the process of muscle contraction, allowing for the generation of force required for various athletic activities. Inadequate calcium levels might lead to muscle weakness, cramping, and decreased performance.*

Calcium and sports - recovery

In addition to its role in performance, calcium may also be important for the recovery process following intense physical activity.* During exercise, micro-damage may occur within the muscle fibers, necessitating repair and regeneration.

Calcium is involved in the activation of various enzymes responsible for cellular repair, making it a potential nutrient for post-exercise recovery.* Furthermore, calcium may help to support the integrity of the skeletal system, providing a foundation for athletes engaging in high-impact sports that place significant stress on bones and joints.*

Calcium and sports - recommendations

To support optimal performance and recovery, athletes should prioritize calcium-rich foods in their diets. This includes dairy products, leafy green vegetables, fish with edible bones, nuts, seeds, and calcium-fortified products.

Depending on the intensity and duration of their training, athletes may have higher calcium requirements than the general population. In these cases, calcium supplementation might be added to help potentially meet the increased demand.* It is essential for athletes to consult with a sports nutritionist or healthcare professional to determine the appropriate calcium intake based on their specific needs and training regimen.

By maintaining adequate calcium levels, athletes may support their performance, facilitate recovery, and have an impact on the risk of injury, allowing them to compete at higher potential.*

In conclusion, calcium is an essential mineral with a wide range of functions in the human body, playing a critical role in bone health, nerve transmission, muscle function, and blood clotting. As such, ensuring adequate calcium intake is vital for individuals of all ages and activity levels. By consuming a balanced diet rich in calcium-containing foods, individuals can support optimal health and well-being. In cases where dietary intake is insufficient or specific health conditions warrant supplementation, calcium supplements might be a valuable addition to one's nutrition regimen.*

However, it is crucial to be aware of the potential risks and side effects associated with excessive calcium intake and consider factors such as absorption, bioavailability, and medication interactions when choosing a calcium supplement. Consulting with a healthcare professional before starting any supplement regimen is always recommended.

Throughout history, calcium has played a significant role in human civilization, and our understanding of its importance in maintaining health and its involvement in various physiological processes continues to grow. By staying informed about the latest research on calcium supplementation and prioritizing calcium-rich foods, certain individuals might help their bodies with the necessary building blocks for supporting health and well-being, whether they are athletes striving for peak performance, aging individuals focused on maintaining bone health, or anyone seeking to support their overall health.* You may also want to read about magnesium glycinate.

As always, talk to your doctor before taking any supplements. Get professional advice if you think you might need a calcium supplement or are already taking one to ensure you're not exceeding the amounts you may need.