Introduction:
Calcium is one of the essential minerals in the body that can be obtained through various dietary sources. Calcium is highly essential for keeping bones and teeth healthy. The major part of body calcium is stored in bones, and a small portion is circulated in the blood. When the blood calcium levels drop down, the body will respond by releasing bone calcium by stimulating the bone resorption process. This is done to maintain the blood calcium levels. Calcium levels are regulated in the body by parathyroid hormone (PTH) that is produced by the parathyroid glands.
It regulates the calcium levels in the body in the following ways:
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By releasing bone calcium into the bloodstream.
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By increasing calcium absorption in the intestine via Vitamin D synthesis.
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By calcium reabsorption from urine by the kidneys.
The other two hormones that help in calcium level regulation in the blood include calcitonin and calcitriol (1, 25 dihydroxy vitamin D). The various functions of calcium in the body include,
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Maintaining healthy bones and teeth and increasing their strength.
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Helps in blood clotting by activating the blood clotting factors.
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Stimulating muscle contraction and relaxation.
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Facilitating nerve-to-nerve communication.
A high intake of calcium may decrease the risk of one or more types of cancer. Adequate intake of calcium helps in reducing the risk of getting colorectal cancer as compared to individuals who intake less calcium. However high intake of calcium may increase the risk of getting prostate cancer. Calcium can help in preventing the bone weakness that occurs with certain chemotherapy medications.
How Much of Calcium Intake Is Required Daily?
An optimum intake of calcium every day is highly essential for a healthy life. The daily requirement of calcium intake differs according to age. A high intake of calcium is required between the ages of 9 to 18 as bone growth is rapid during this time. An adult requires an average of 1000 mg of calcium per day, whereas the requirement rises to 1200 mg for women above 50 years of age and men above 71 years of age.
A study was conducted by the American cancer society to analyze the relationship between diet and lifestyle factors with the risk of cancer causation, mortality, and survival. The study found that men and women who took high intakes of calcium through their diet and supplements showed a reduced risk of colorectal cancer development as compared to individuals who had low calcium intake. The study revealed that a calcium intake of 1200 mg per day is beneficial in reducing the risk of colorectal cancer development.
Although a high intake of calcium can prevent certain cancers, it can also lead to an increased risk of getting cancers like prostate cancer. Too much calcium intake than the daily required levels may cause unwanted side effects.
How Does Calcium Reduce the Risk of Colorectal Cancer?
A high intake of calcium shows a reduced risk of colorectal cancer development in individuals. Calcium intake is inversely related to reduced risk of colorectal cancer development. The exact mechanism behind calcium reducing the risk of colorectal cancer development is unclear. However, certain studies revealed the different ways through which calcium prevents colorectal cancer; these include:
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Binding of calcium to bile and fatty acids in the gastrointestinal tract form insoluble complexes. These insoluble complexes are known as calcium soaps. It reduces the potential of acids to cause cell damage in the lining of the colon and also helps in repairing the damage by stimulating cell proliferation.
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On the other hand, calcium may act directly to reduce cell proliferation in the colon lining or cause differentiation of proliferating colon cells to reduce cell proliferation.
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Calcium can also prevent cancer by improving signaling within cells that cause either differentiation of cancer cells or death of cancer cells.
Men and women who had adequate calcium intake per day showed a reduced risk of colorectal cancer. A study revealed that men and women who had more than 700 mg/day of calcium intake showed up to 45% reduced risk of cancer development at the lower (distal) part of the colon as compared to those who had a calcium intake of 500 mg/day or less than that. However, the scientific evidence of calcium supplementation protecting against colorectal cancer is limited and inconsistent.
Does Calcium Help in Breast Cancer Prevention?
In 2010, at the American Association for Cancer Research, a study was presented which showed that people taking vitamin and calcium supplements or calcium alone help in breast cancer prevention by 30 to 40 %. It especially helps in preventing breast cancer in pre-menopausal women. Calcium intake of more than 800 mg/day from sources like low-fat milk, cheese, and yogurt may help in breast cancer prevention compared to a low calcium intake of less than 200 mg/day.
Are There Any Other Cancers That May Be Prevented by High Calcium Intake?
Studies have revealed that a high calcium intake may reduce the risk of one or more cancer types, whereas, on the other hand, some studies suggest that high calcium intake may increase the risk of cancer. A high intake of calcium is known to increase the risk of prostate cancer. There is not much scientific evidence regarding calcium preventing cancers other than colorectal and breast cancer. Many scientific studies and research are still going on to find the role of calcium in cancer prevention.
How Are Calcium Carbonate Nanoparticles Used for Cancer Drug Delivery System?
The extracellular pH of the tumor microenvironment is highly acidic. This acidic environment is very important for metastatic growth, which causes cancer to kill people. In order to alter the acidic microenvironment of the tumor and decrease its progression, nanoparticles made from calcium carbonate are used. Calcium carbonate nanoparticles as a cancer drug delivery systemare initially injected into an animal model to treat tumors. This results in raising the pH of the tumor microenvironment to be alkaline which prevents cancer growth further. Calcium carbonate nanoparticles can raise the pH of the tumor microenvironment to 7.4 (normal pH of the body).
Is Excess Calcium Harmful to Health?
A high intake of calcium, in certain instances, can cause damage to health. It can lead to complications like kidney stones, cardiovascular diseases, and hypertension and is also associated with an increased risk of cancer. Excess calcium intake may increase the risk of prostate cancer. Adequate intake of calcium can be easily obtained through daily dietary sources, and usually, no additional calcium supplementation is required. If you are thinking of adding calcium supplementation along with your diet, then it is advisable to consult your doctor.
Conclusion:
An adequate calcium intake daily may prevent the risk of certain cancers like colorectal cancer and breast cancer. Calcium intake is inversely related to a reduced risk of cancer. However, there is not much conclusive evidence regarding calcium reducing the risk of cancer development. People who are affected by colorectal and breast cancer may require cancer supplementation. You need to consult a doctor before adding any calcium supplementation to your daily life to know whether it is appropriate for you or not.
