Calcium Overview, Health Benefits, Source Food, Deficiency, Side effects

Calcium Overview, Health Benefits, Source Food, Deficiency, Side effects

Calcium Overview

Calcium is a mineral important for strong bones and teeth. Too little calcium can lead to the bone conditions rickets and osteoporosis.

The human body utilizes the mineral calcium as one of the main structural building compound to form various hard organic systems. Calcium imparts hardness and strength to the skeletal system and the teeth and almost ninety nine percent of the human body's total three pounds of calcium is in the skeleton and the dentition - calcium also functions in synapse communication in the neurons of the brain. The bones and the teeth can be said to be reservoirs of the mineral calcium, and the mineral in the bones and teeth is not permanently entrenched - it can be transported to other areas or lost in the urine during a disorder or with increasing age. Calcium is almost constantly being exchanged between the bones and the body fluids or even the soft tissues - where the remaining calcium is stored and utilized in various biochemical processes. As a relatively constant blood level of calcium is maintained and regulated by homeostatic processes in the body, there is a distinct danger in the event of insufficient dietary intake of calcium, the amount lost through excretion and loss from the bones may not be replenished - this will inevitably give rise to a deficiency in the mineral.

Calcium also has a role in blood clotting and the regulation of muscle contractions including the heartbeat.

There is some evidence calcium has a role in managing blood pressure and preventing breast and colon cancer.

Due to its great importance both in forming organic structures and its role in physiological reactions calcium is naturally of vital importance for the growth and development of an individual. The importance of calcium is underlined by the fact that during the final trimester of pregnancy, about 200 and 300 mg of calcium is deposited daily in the skeleton of a developing human fetus - all of this calcium is sourced from the mother. As a child is nursed, calcium is again sourced from the mother via the breast milk - which has a calcium content from about 250 to 500 mg of calcium - the growing child receives about this much calcium from his or her mother though breast feeding. Pregnant or lactating women will suffer from a loss of calcium if the amount of calcium lost in the milk or in supplying the fetus is not equaled by the amount supplied through the diet - most of the calcium going to the milk of to the developing child will then be coming out of her bones, the health of both the mother and child will be affected and skeletal system of both mother and child will be weakened. Therefore, it is vitally essential that pregnant or lactating women consume sufficient calcium in the daily diet.

Most people should get enough calcium from a balanced healthy diet, but calcium supplements may be recommended for some people. Calcium forms 2% of total body weight in a human adult. Calcium is found in the human body as deposits in the bones and teeth in high volumes. Traces of calcium are also present in the circulatory system, which prevent life threatening hemorrhages.

Why do people take calcium?

Calcium is crucial in growing new bone and maintaining bone strength. Calcium supplements are standard for treating and preventing osteoporosis -- weak and easily broken bones -- and its precursor, osteopenia.

Calcium is used for many other conditions. It's an ingredient in many antacids. Doctors also use calcium to control high levels of magnesium, phosphorus, and potassium in the blood. There's good evidence that calcium can help prevent or control high blood pressure. It also may reduce PMS symptoms as well as play a role in preventing certain cancers. Calcium with vitamin D, for instance, may help protect against breast cancer in premenopausal women. The data, though, are still inconclusive as to whether it might do the same for postmenopausal women. Calcium also has been looked at for other uses, for example, aiding weight loss. But so far, these studies have been inconclusive.

The people at highest risk of a calcium deficiency are postmenopausal women. Since dairy products are one of the most common sources of calcium, people who are lactose intolerant or vegan are also at increased risk of calcium deficiency.

Health benefits of Calcium

Calcium is crucial in growing new bone and maintaining bone strength. Calcium supplements are standard for treating and preventing osteoporosis -- weak and easily broken bones -- and its precursor, osteopenia.

Strengthens Bones

Calcium strengthens the backbone and ensures the right shape to the body, as well as helping to alleviate the presence of back pain. Calcium helps to keep the bones in their proper shape and prevents many skeletal complaints like arthritis and osteoporosis, which could hamper your freedom of movement, as well as being extremely painful.

Protects Cardiac Muscles

Calcium protects your heart muscles. Sufficient amounts of calcium can help cardiac muscles to contract and relaxat properly. Calcium also helps the nervous system maintain the proper pressure in your arteries. If there is a calcium drop, a hormone called calcitrol is released, which contracts the smooth muscles of the arteries, thereby increasing the blood pressure. Cardiac muscles need extracellular calcium ions for contraction. When the intracellular concentration of calcium increases, the calcium ions gather together on the protein troponin. This stimulates the secretion of extracellular fluid and the intracellular stores, including that of the skeletal muscle, which is only activated by calcium stored in the sarcoplasmic reticulum.

Prevents Colon Cancer

Adequate calcium prevents overall risk of colon cancer and suppresses the growth of polyps that can lead to cancer. Calcium supplementation reduces the risk of adenomas, as well as nonmalignant tumors in the colon. This is actually a precursor to colon cancer, but it’s still not known if calcium intake minimizes the cancer risk completely. The excess calcium is left in your intestines after your body absorbs what it needs. On its way through the colon, this unabsorbed calcium is believed to bind with cancer promoters so they’re excreted together from the body. Studies have shown that both food sources of calcium and calcium supplements provide this protective effect. Calcium supplements should be taken in liquid form because liquid vitamins absorb 5 times better than the pills.

Prevents Obesity

Calcium efficiently helps in maintaining optimal body weight in both males and females. If there is any deficiency in calcium in your diet, the body will tend to release parathyroid hormone, which in turn stimulates the bones to release calcium into your blood stream. This maintains the balance. On the other side, parathyroid hormone also stimulates the production of fat and prevents its break down, which can subsequently make you obese. Basically, make sure that you are taking the right amount of calcium, but not too much, so that obesity does not creep in, alone with other related health hazards.

Prevents Premenstrual Depression

Adequate amounts of calcium lessen the symptoms of premenstrual syndrome like dizziness, mood swings, hypertension and many others. Low levels of calcium might trigger the release of the hormones that are responsible for premenstrual mood swings including irritability and depression.

Prevents Kidney Stones

Kidney Stones are actually crystallized deposits of calcium and other minerals in the human urinary tract. The most common form of kidney stones is oxalate stones. Previously, it was thought that high calcium intake or high calcium absorption develops kidney stones, but the latest studies show that high dietary calcium intake decreases the risk of kidney stones considerably. In short, dietary calcium does not cause kidney stones, but the excess calcium present in water results in kidney stones. Other factors like high oxalate consumption from leafy vegetables like kale and spinach, as well as reduced fluid consumption can prove to be a big cause for kidney stones.

Maintains Healthy Teeth and Gums

Calcium protects your teeth by keeping the jaw bone strong and sturdy throughout your life, which in turn ensures tight fitting teeth where bacteria cannot thrive. Thus, before your teeth and gums start giving you any trouble, be sure to maintain a calcium rich diet. Calcium intake should be high, especially at young ages, so that your children naturally grows up with strong teeth.

Ensures a Healthy Alkaline pH Level

Junk foods, excess sugars, and preserved food items contribute in forming acidity in the body, which in turn could give rise to various disease conditions like cancer, kidney stones and hypertension. Calcium helps to maintain a healthy pH level, thereby improving your vitality and overall health.

Controls Blood Pressure

Some research has stated that a vegetarian diet with high amount of calcium, magnesium, potassium, and fiber will result in reduced blood pressure. While other researchers concluded with different opinions and said that increased calcium intake results in hypertension. Later, it was seen that the reason for such assorted results was because these studies tested the effect of single nutrients rather than the food sources having that nutritional content. The National Institutes of Health conducted a research study called “Dietary Approaches to Stop Hypertension (DASH)“. The “typical American” diet was compared with two altered diets that were rich in fruits-and-vegetables and a combo “DASH” diet stuffed with fruits, vegetables, and calcium. The results showed that increased calcium intake results in decreased blood pressure.

To help test the combined effect of nutrients including calcium from food on blood pressure, a study was conducted to investigate the impact of various eating patterns on blood pressure. This study examined the effects of three different diets on high blood pressure and found that the combined effects with various foods still showed calcium to be beneficial in terms of blood pressure.

Overall, it appears that consuming an adequate intake of fruits and vegetables as well as calcium plays a significant role in controlling blood pressure.

Helps in Transportation of Nutrients

Calcium helps in the easy movement of nutrients across cell membranes.

Good food sources of Boron

Mother's milk is the best source of calcium for a new born baby; human milk has calcium to phosphorus ratio of about 2.4:1 and is the ultimate source of nutrition for a growing child. A good natural source of calcium for everyone else is of course, cow's milk, this has a calcium to phosphorous ratio of 1.2:1, it is not necessary the best or the only natural source of the mineral calcium - many other animals posses milk far more nutritious in mineral content, we just do not use them. Calcium is also abundant in egg yolk and fish when consumed whole, vegetable sources such as soybeans, green leafy vegetables like turnip greens and mustard greens, broccoli and kale, various roots and tubers and all plant seeds are rich in calcium content. Significant amounts of calcium can also be obtained by consuming all types of stews and soups made from bones. The absorption of calcium in the body is also positively affected by the presence of lactose - the sugar found in milk and all dairy products.

Calcium is found in a variety of foods, but the amount that your body absorbs varies. Oxalic acid and phytic acid both interfere with the absorption of calcium. Foods rich in oxalic acid are spinach, rhubarb, sweet potatoes, and beans. Foods rich in phytic acid are unleavened bread, nuts, seeds, and raw beans. You will absorb some of the calcium in these foods, but not as much as you would from foods that do not contain oxalic acid or phytic acid. For example, calcium absorption from dried beans is about half of what you absorb from milk, and calcium absorption from spinach is about one-tenth of that absorbed from milk. There is no need to omit these foods from your diet. Instead, consume a variety of calcium-rich foods throughout the day.

Many other compounds containing calcium can be used as supplements - thus calcium can be consumed in the form of calcium carbonate, in the form of calcium gluconate, calcium lactate and many other compounds of calcium. There is no “best” supplement as scientist have not been able to come up with a general agreement on the best supplemental form of calcium. Using more than one supplemental form of calcium at the same time is probably wise in treating any deficiency. Supplements of the vitamin D also need to be taken along with the supplemental calcium as this vitamin is essential for the proper absorption and utilization of calcium in the body. A wide array of dosage levels are intended with supplemental use of calcium, supplemental tablet at less than 100 mg to several hundred milligrams each are available in the market.

Dairy products of all kinds and milk are the main source of most dietary calcium. Scientific research has not conclusively proved the belief that calcium sourced from dairy products is absorbed optimally in the body. Good natural sources for the mineral calcium include also foods like sardines and canned salmon, as well as tofu from soybeans.

Since there are so many supplemental forms of calcium, it can be difficult to make a choice about the best form of calcium supplement to use during the process of supplementation. The absorption rate of supplemental calcium carbonate is not as good as the other supplemental forms of calcium, however, less pills of this form are needed during the period of supplementation - therefore, and this form of calcium is considered ideal as a supplement. The result of the majority of scientific studies but by no means all clinical studies, suggests that absorption rate of calcium citrate is better than the absorption of the calcium carbonate supplemental form. At the same time, almost all the comparative studies done on the absorption rate of calcium citrate-malate - CCM - supplements suggests that it is absorbed a lot better than the supplemental calcium carbonate in human beings. Nutritionally oriented doctors tend to recommend the supplements of CCM and increasingly prefer this form of supplement to all other supplemental forms of calcium. Bone mass in humans is also improved by the microcrystalline hydroxyapatite - MCHC -  form of supplemental calcium, this is a chemical variation of the bone meal form of the mineral calcium. However, the absorption rate of MCHC appears to be poor compared to other forms of calcium normally used in supplemental regimes. Conclusions cannot be drawn at this present time as far as the use of amino acid chelates of calcium as supplements is concerned - this is because only preliminary research exists as far as their use in humans is concerned. Further studies need to be conducted before these compounds can be considered safe for use in supplements.

Symptoms of Calcium Deficiency

When both calcium and vitamin D deficiency exists in the body, the physical symptoms exhibited by the person are called rickets when it affects children and osteomalacia when it affects adults. A deficiency of the vitamin D is much more likely to affect vegans - pure vegetarians who avoid dairy products and eggs, people with dark skin, and populations of the far northern climates, as well as people staying indoors most of the time. When compared to other people, vegans typically consume far lesser calcium and vitamin D in the diet - since, their diet is so restricted to plant matter. At any rate, the majority of people are provided with calcium at levels far below the recommended amounts in the diet. The greater risk of osteoporosis that many white and Asian women face is believed to be this lack of dietary calcium in the normal diets of such women.

The people at highest risk of a calcium deficiency are postmenopausal women. Since dairy products are one of the most common sources of calcium, people who are lactose intolerant or vegan are also at increased risk of calcium deficiency.

Recognizing calcium deficiency in the body is quite easy. It occurs when your muscles ache and twitch, or if you get sudden cramps and spasms. Also, if you suffer from palpitations, high blood pressure, osteoporosis, loose teeth and gum diseases, insomnia, premenstrual cramps, tetany, hypertension and arthritis, that may also indicate calcium deficiency. Often, many children suffer from rickets, where the bones become weak and flexible, they have bowed legs, sunken chests and beaded ribs. These children have not been nourished with calcium since birth.  Thus, a regular calcium supply is very important in growing children and teenagers as it can substantially reduce the risks of osteoporosis in old age. This bone ailment is common in one out of every three women and in one man in every 12, above 50 years of age.

The onset of disorders like rickets in children, osteomalacia and osteoporosis in adults is directly attributable to the lack of the mineral calcium in the diet.

Calcium deficiencies have also other serious effects besides their well known effects on bone mineralization and faulty nerve and muscle irritability. Lack of calcium in the body could also play a role in the inhibited rising blood and tissue levels of two well known poisonous metals - lead and cadmium. The human body tends to retain more lead whenever the levels of dietary calcium are low. These connections between the mineral calcium and related bio-chemical events in the body have been directly demonstrated in many experiments conducted on humans and animal test subjects. It is now known that very low levels of calcium in the diet can induce high blood and tissue levels of the metal lead.

When levels of calcium are low in the body, the metal cadmium, a toxic pollutant, also tends to be retained by the body at higher concentrations - this can have drastic implications for the health of the concerned person.

Other factors can put you at risk for low calcium levels.


Research has shown that young women who do not get their period due to anorexia nervosa have reduced net calcium absorption, higher urinary calcium excretion, and a lower rate of bone formation in comparison to those who menstruate regularly. Reduced calcium retention and lower bone mass have also been seen in exercise-induced amenorrhea.

Lactose intolerance

Many people find that consuming dairy products causes bloating, gas, cramping, and/or diarrhea. This is often from your body's inability to break down the lactose found in dairy foods. Lactose is the sugar that naturally occurs in these foods. Avoiding dairy foods can put you at risk for calcium deficiency. Fortunately, there are things that you can do to help with these symptoms. The first thing is to try to consume smaller amounts of dairy foods. Studies have shown that people with lactose intolerance can often tolerate 8 oz of milk at once. When this doesn't work, you can purchase dairy products that have the lactose broken down for you. Lactaid products have taken the lactose and broken it up so that your body does not have to.

Calcium Side effects and cautions

Supplemental use of calcium has been linked to specific physical symptoms such as persistent constipation, abdominal bloating and excessive gas. The consumption of calcium carbonate supplements along with large amounts of calcium received by consuming large amounts of dairy products was the cause of a condition formerly known as "milk alkali syndrome" - a toxic effect of accumulated calcium in the body. Medical doctors used to recommend people affected by ulcers to take this supplemental combination as a treatment, but they no longer do so these days and hence, such toxic symptoms are no longer common in the general population.

Supplements of calcium must not be used by individuals affected by disorders like hyperparathyroidism or diseases like chronic kidney disease as it can worsen things. Such patients must always consult with a nutritionally oriented physician on the possibility of supplementing with calcium before they go ahead. Supplementation using calcium for those individuals with kidney stones must also be done only after consulting with a doctor - they should supplement only after receiving an okay from the doctor. As far as supplemental use of calcium for healthy adults is concerned, the best may be the highest amount normally recommended by nutritionally oriented doctors, this is a dose of 1,200 mg daily. Such dosages are quite safe and are not linked to any adverse side effects.