Calcium
Calcium, the major mineral for strong bones and teeth
Calcium is the most abundant mineral in the body.
The baby's body contains about 26 to 30 grams of calcium at birth. This amount rises quickly after birth, reaching nearly 1,400 grams in men and 1,200 grams in women by adulthood. These calcium levels remain constant in men. In women, due to the decreased estrogen production at the start of menopause, the calcium levels start to drop because of increases in bone remodeling.
Calcium -the major mineral for strong bones and teeth
Calcium is the most abundant mineral in the human body, making up 1.5%-2% of the body by weight.
Calcium is a mineral the body needs to build and maintain strong bones and teeth and to carry out many essential functions. Almost all calcium in the human body is stored in teeth and bones, giving them structure and strength.
Approximately 99% of the body’s calcium is in bones and teeth; the remaining 1% is in body fluids and cells. In addition, calcium circulates in the blood, maintaining a constant level so that calcium is always available for use.
Calcium helps to send and receive nerve signals, and contract and relax muscles. In addition, calcium is needed for heart and digestive system health. Calcium also helps hormone secretion.
What does calcium in our bodies?
1. Bones and teeth: Calcium builds bones and maintains healthy bones; calcium builds bones by becoming part of bone tissue. Calcium supports the structure and hardness of bones and teeth. Vitamin D helps the body absorb calcium.
2. Muscle: Calcium helps muscle contract and relax. The body needs calcium for muscle function. Calcium allows normal bodily movement by keeping tissue flexible, solid, and rigid.
3. Nerve Transmission: Calcium helps the body in nerve transmission. The body needs calcium for nerves to carry messages between the central nervous system and every body part.
4. Blood circulation: Calcium helps blood vessels move blood throughout the body. Calcium helps mediate blood vessel contraction and dilation, helping blood vessels carry blood throughout the body. Calcium also helps blood clot if bleeding as it is of the 13 blood clotting factors.
5. Hormones and enzymes: Calcium helps release different hormones and enzymes.
Calcium, How do we maintain healthy bones?
Bones are living tissues and are being rebuilt every day. New bone is formed, and old bone is taken apart. Therefore, the calcium in bones is in a state of constant change.
Bone health equals the addition of good nutrition plus physical activities.
The basic strategies for healthy bones:
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Eat various foods to get enough nutrients, including calcium, vitamin D, phosphorus, magnesium, and protein, for strong and healthy bones.
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Participate in regular weight-bearing activities.
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Avoid smoking and excessive amounts of alcoholic beverages, as both interfere with bone health.
Bones are living tissues, which means bones are in a constant state of change! For example, calcium gets deposited on bones and withdrawn daily from the body's skeleton. In addition, bone tissues are in a process called remodeling, in which older bone tissues are replaced with new bone tissues.
Therefore, to keep bones strong and to reduce bone loss, calcium must be deposited into bones regularly to replace the bone losses.
Calcium plays a similar role in teeth. However, the turnover of minerals in teeth is slower than in bones. Fluoride, a trace mineral, hardens and stabilizes the teeth and decreases the turnover of minerals in teeth.
To maintain healthy bones and teeth. First, we need a good nutrition diet.
Calcium works with other nutrients, including magnesium, phosphorus, and vitamin D. Phosphorus and Magnesium help build and maintain bone health. Vitamin D helps absorb, carry, and deposit calcium in bones and teeth.
In addition to good nutrition, physical activities such as regular weight-bearing activities, strength training, and walking are essential to bone health, too. This is because physical activities trigger nerve impulses and activate the body to deposit calcium in bones. Conversely, when there is a lack of physical activities, the body does not signal that it needs calcium, which means that calcium is excreted without absorption.
Food sources of calcium:
Calcium is contained in many foods, including the following.
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Milk and milk products such as yogurt and most cheeses are the best sources of calcium.
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Canned salmon and sardines with bones contain calcium.
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Green leafy vegetables such as kale, cabbage, and broccoli are also good sources of calcium.
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Tofu made with calcium sulfate supplies significant amounts of calcium.
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Soy milk with fortified calcium is a good source of calcium.
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Bread and anything made with fortified flour is a good source of calcium.
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Check the product labels for calcium-fortified foods such as orange juice and cereal.
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Dried beans, peas, and nuts such as almonds contain moderate amounts of calcium that can contribute to calcium intake when eaten in sufficient quantities.
Oxalic acid and phytic acid lower the bio-availability of calcium:
About 30% of the calcium we eat from dairy products and fortified foods is absorbed. Interestingly, calcium from plant-based foods is less bio-available than from dairy foods because the phytochemicals in some plant-based foods hinder calcium absorption by the body.
For example, oxalic acid in spinach and phytic acids in grains bind with some minerals, including calcium, iron, and magnesium, and partially block their absorption by the human body. Therefore, the absorption rate of calcium from spinach is only about 5%. Foods with high levels of oxalic acid include collard greens, sweet potatoes, rhubarb, and beans.
Interestingly, broccoli, kale, and cabbage do not contain the acids to block calcium absorption. Therefore, we need to eat various foods to maintain healthy bones and teeth.
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The top food sources of calcium:
1. Yogurt
2. Cheese
3. Milk
4. Orange juice, calcium-fortified
5. Soy milk, calcium-fortified
6. Tofu, made with calcium sulfate
7. Soybeans
8. Spinach
9. Turnip greens
10. Kale
11. Chia seeds
12. Cabbage
13. Beans and peas
14. Broccoli
15. Apples
16. Breakfast cereals, calcium-fortified
How much Calcium do I need?
The RDAs for calcium are listed in the table.
The RDAs of calcium for adults were the amount needed to promote bone maintenance and neutral calcium balance. For infants aged zero to twelve months, AI of calcium was established as equivalent to the mean calcium intake in healthy breastfed infants. For children and adolescents, the RDAs of calcium are based on intakes associated with bone accumulation and positive calcium balance.
References:
Institute of Medicine. Dietary Reference Intakes for Calcium and Vitamin D. Washington, DC: The National Academies Press; 2011.
https://ods.od.nih.gov/factsheets/Calcium-HealthProfessional/#en1 Updated: October 6, 2022
UL for Calcium:
Do not consume excess amounts of calcium. Calcium can be toxic when large doses of supplements are taken. Do not over-consume calcium. The tolerable upper intake level for calcium for adults 19-50 years is 2500 milligrams daily. The amounts above that cause adverse effects for adults. For example, the development of calcium deposits in the kidneys causes kidney stones.
There are health risks from excessive calcium. The ULs for calcium established are listed in the following table. The daily upper limits for calcium include intakes from all sources, including food, beverages, and supplements.
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The ULs for Calcium are listed in the above table.The daily upper limits for calcium include intakes from all sources—food, beverages, and supplements—and are listed below.
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References:
Institute of Medicine. Dietary Reference Intakes for Calcium and Vitamin D. Washington, DC: The National Academies Press; 2011.
https://ods.od.nih.gov/factsheets/Calcium-HealthProfessional/#en1 Updated: October 6, 2022
Calcium and Healthful Diets:
People should get most of their nutrients from food and beverages. Our nutritional needs should be met primarily through foods because foods provide an array of nutrients ( vitamins, minerals, dietary fibers) and other components that have benefits for health.
In some cases, fortified foods and dietary supplements are helpful when it is impossible to meet needs for one or more nutrients, for example, during specific life stages such as pregnancy.
A healthy eating pattern described by The Dietary Guidelines for Americans is one that:
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Includes a variety of vegetables, fruits, whole grains, milk and milk products, and oils. Many dairy products, such as milk, cheese, and yogurt, are rich sources of calcium. Some vegetables provide significant amounts of calcium, as do some fortified cereals and juices.
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Includes a variety of protein foods, including lean meats and poultry, eggs, seafood, legumes (beans and peas), nuts and seeds, and soy products. As calcium salts are used in making Tofu, Tofu is a good source of calcium ( you need to check the label). Seafoods, such as canned sardines and canned salmon with edible bones, are also good sources of calcium.
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Limits foods and beverages higher in added sugars, saturated fat, and sodium.
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Limits alcoholic beverages.
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Stays within your daily calorie needs.
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Reference:
https://www.dietaryguidelines.gov
https://ods.od.nih.gov/factsheets/Calcium-HealthProfessional/ Updated: October 6, 2022
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