Calcium is one of the important for our health. Calcium is needed for our bone development, heart,muscles, and nerves to function properly and for blood to clot. Inadequate calcium significantly contributes to the development of osteoporosis. Many published studies show that low calcium intake throughout life is associated with low bone mass and high fracture rates. National nutrition surveys have shown that most people are not getting the calcium they need to grow and maintain healthy bones.
We can get calcium through calcium rich foods and calcium supplement. But now it becomes a trend for our doctors that any deficiency of calcium they found in a patient, they prescribe high dosages of calcium supplements.
Recommended Calcium For Human
Intake recommendations for calcium and other nutrients are provided in the Dietary Reference Intakes (DRIs) developed by the Food and Nutrition Board (FNB) at the Institute of Medicine of the National Academies (formerly National Academy of Sciences). DRI is the general term for a set of reference values used for planning and assessing the nutrient intakes of healthy people. These values,which vary by age and gender, include:
- Recommended Dietary Allowance (RDA): average daily level of intake sufficient to meet the nutrient requirements of nearly all (97%–98%) healthy individuals.
- Adequate Intake (AI): established when evidence is insufficient to develop an RDA and is set at a level assumed to ensure nutritional adequacy.
- Estimated Average Requirement (EAR): average daily level of intake estimated to meet the requirements of 50% of healthy individuals. It is usually used to assess the adequacy of nutrient intakes in populations but not individuals.
- Tolerable Upper Intake Level (UL): maximum daily intake unlikely to cause adverse health effects.
The FNB established RDAs for the amounts of calcium required for bone health and to maintain adequate rates of calcium retention in healthy people. They are listed in Table 1 in milligrams (mg) per day.
The New Study on Calcium Supplements Intake
People who take calcium supplements may be at increased risk for developing buildups of plaque in their arteries, which is a sign of heart disease, a new study found.
But,people who consume a lot of calcium through the food they eat may actually beat a lower risk of heart disease, the study showed.
The new findings add to a growing body of evidence that some dietary supplements, such as calcium supplements, may have harmful effects.
"When it comes to using vitamin and mineral supplements, particularly calcium supplements being taken for bone health, many Americans think that more is always better," study co-author Dr. Erin Michos, associate director of preventive cardiology at the Johns Hopkins University School of Medicine in Baltimore, said in a statement. "But our study adds to the body of evidence that excess calcium in the form of supplements may harm the heart and vascular system."
For the calcium supplement research, the scientist analyzed information from more than 2,700 people ages 45 to 84, who answered questions about their calcium intake, from both their diets and supplements.
The research participants also underwent two CT scans, one at the beginning of the study and another 10 years later. The scans looked for plaques containing calcium in the arteries of the heart, which are the coronary arteries. The presence of such calcium-containing plaques means that a person is at increased risk of developing heart disease, or having a heart attack. At the start of the study, about 1,500 people did not have any calcium-containing plaques in their arteries.
The participants were then divided into five groups based on the individuals' calcium intake from both their diets and supplements by the researchers.
Those people with the highest intake of calcium (greater than 1,400 milligrams per day) were actually 27 percent less likely to develop calcium-containing plaques in their coronary arteries over the 10-year study, compared with the group with the lowest intake of calcium (less than 400 mg per day). Moreover, the people in the highest-intake group who achieved their high calcium intake without supplements were at an especially low risk of developing plaques, according to the study.
In contrast, people who took calcium supplements were overall 22 percent more likely to develop calcium-containing plaques over the study period, compared with those people who didn't use such supplements. Forty-six percent of people in the study used calcium supplements.
It's possible that large doses of calcium consumed in supplements may temporarily elevate calcium levels in the blood,which leads to calcifications in blood vessels, the researchers said.
"There is clearly something different in how the body uses and responds to supplements versus intake through diet that makes it riskier," said study co-author John Anderson, a professor emeritus of nutrition at the University of North Carolina at Chapel Hill. "It could be from taking a large dose all at once that the body is unable to process."
The researchers noted that they found only an association and cannot prove that taking calcium supplements causes an increase in the risk of developing calcium-containing plaques and heart disease. In addition, the participants self-reported their calcium intake, and it's possible they did not always remember their intake correctly, which could affect the results, the researchers said.
Previous research supports the new study's results, though. A 2012 study from Sweden found that consuming high amounts of calcium was linked with an increased risk of dying from any cause during the study period, including from heart disease.
The researchers said their new results are "hypothesis generating" and should spur more research in this area.
"Based on this evidence, we can tell our patients that there doesn't seem to be any harm in eating a heart-healthy diet that includes calcium-rich foods, and it may even be beneficial for the heart," Michos said. "But patients should really discuss any plan to take calcium supplements with their doctor to sort out a proper dosage or whether they even need" such supplements.
The study was published Oct. 11 in the Journal of the American Heart Association.
Calcium Rich Foods
Calcium is the most abundant mineral in the body,and is found naturally in a wide variety of foods and beverages and added to many others! However, a large percentage of the population does not get enough calcium from the diet
The main foods rich in calcium are dairy products like milk, cheese and yogurt. However, many non-dairy sources are also high in this mineral.
These include seafood, leafy greens,legumes, dried fruit, tofu and various foods that are fortified with calcium.