What is Calcium?
Calcium is a mineral that is essential for living organisms. It is a structural element in bones and shells and it serves as a necessary messenger in cell physiology. For example, calcium is involved in muscle contraction, the electrical conduction of the heart, and neurotransmitter release. Calcium combines with phosphate to form hydroxylapatite, which is what is found in bones and teeth.
Where is Calcium found?
Calcium can be found in dairy products, such as milk, cheese, and yogurt. Other good sources are seaweeds (kelp, wakame, hijiki), almonds, hazelnuts, sesame, pistachio, blackstrap molasses, beans, figs, quinoa, okra, rutabaga, broccoli, dandelion leaves, kale, fish with soft bones (canned salmon and sardines), and fortified products like certain brands of orange juice.
Calcium is also sold in supplements. When taking calcium pills, no more than 600mg should be taken at a time for ideal absorption, and therefore the pills should be taken throughout the day. Some of the different forms of calcium supplements are: calcium carbonate (most common and least expensive), calcium citrate, calcium phosphate (microcrystalline hydroxyapatite), coral calcium, calcium lactate and calcium chelates.
What are the benefits of Calcium?
Calcium is used to prevent and treat hypocalcemia, osteoporosis, and rickets. It is also effective in treating hyperkalemia (high potassium levels), renal failure, and dyspepsia (calcium carbonate is used as an antacid). Calcium is also used to treat hyperparathyroidism and to decrease PMS symptoms. For some, it reduces the risk of colorectal cancer, fluorosis, hypercholesterolemia, hypertension, stroke, pre-eclampsia, and weight loss.
Are there interactions between Calcium and other food, herbs or supplements?
Vitamin D increases the absorption of calcium, whereas many fibers decrease calcium absorption. Calcium supplements may decrease the absorption of dietary iron, zinc and magnesium. High levels of caffeine and high levels of sodium increase calcium excretion and may be linked to bone loss.