Calcium
Requirements:
- RDA:
1,200 mg. for young adults
- Daily Optimal Intake:
1,200 mg. for young adult
Supplement Forms:
- Bone meal - highly absorbable but also contains
phosphorus
- Calcium carbonate - contains greatest amount of elemental
calcium (40%)
- Calcium citrate - most absorbable especially in elderly, but
most expensive
- Calcium chelates - calcium bound to amino acid, good
absorption
- Calcium chloride - good absorption
- Calcium gluconate - good absorption but low in amount of
elemental calcium
- Calcium lactate - good absorption but low in amount of
elemental calcium
- Dolomite - contains both calcium and magnesium but is the
least absorbable
Labs:
- Hair analysis inaccurate
- Total blood levels are very inaccurate for assessing
calcium
Food Sources:
- Almonds: 1/2 cup (186 mg.)
- Blackstrap molasses 1 Tbl. (171 mg.)
- Buttermilk 8 oz. (290 mg.)
- Cheddar cheese 3.5 oz. (721 mg.)
- Clove of garlic large (167 mg.)
- Cow's milk 8 oz. (517 mg.)
- Filberts 1/2 cup (132 mg.)
- Goat's milk 8 oz. (335 mg.)
- Sardines, salmon 1/2 pound (1050 mg.)
- Sesame seeds 1/2 cup (683 mg.)
- Shrimp 1/2 pound (290 mg.)
- Tofu 3.5 oz. (128 mg.)
- Trout 1/2 pound (545 mg.)
- Yogurt 8 oz. (302 mg.)
Signs and Symptoms of Deficiency:
- Muscle cramps
- Osteomalacia
- Osteoporosis
- Rickets
- Tetany
Causes of Deficiency:
- Arthritis
- Blood loss
- Decreased absorption
- Decreased intake especially if eating SAD (Standard American
Diet)
- High intake of sodium
- High intake of sugar
- High phosphorus
- Hypercalcuria
- Inflammatory bowel disease
- Lead toxicity
- Multiple sclerosis
- Senility
Adverse Reactions and Toxicity:
- Constipation
- Contraindicated in:
Asthma
Dialysis patients
Idiopathic stone formers with hypercalciuria
Sarcoidosis
- Usually well tolerated
Drug/Nutrient Interaction:
- Calcium and magnesium compete for GI absorption
- Excessive thyroid hormone may cause excessive excretion of
calcium from bone loss
- High calcium (2,000 mg. per day) can decrease iron
absorption
- High calcium (2,000 mg. per day) can decrease manganese
absorption
- High zinc (150 mg. per day) leads to decrease in calcium
absorption
- If no magnesium is used, calcium may exacerbate digoxin
toxicity
- Increase in sodium intake can lead to an increase in calcium
in the urine
- Increased phosphorus leads to a decrease in active vitamin D
and therefore decrease in calcium
- Supraphysiologic doses of corticosteroids cause calcium
depletion
- Tetracyclines inhibit calcium absorption and vice versa
Biochemical Functions:
- Adds hardness to bone formation
- Aids transport across cell membranes
- Decreases cholesterol and triglycerides
- Decreases plaques (in animal studies)
- Helps regulate membrane stability
- Influences excitability of smooth muscle
- Involved in teeth structure
- Regulates neurotransmitters at synaptic junctions
- Stimulates the release of thromboplastin from platelets
Clinical Indications:
Copyright 1998 - 2008 by L. Vicky Crouse, ND and James S. Reiley, ND. All rights reserved (ISSN 1527-0661).