Calcium: benefits, dosage, contraindications
Other name(s)
Ca
Family or group:
Minerals and trace elements
Indications
Scoring methodology
EFSA approval.
Digestive disorders ✪✪✪✪✪
A dose of 750 mg four times a day of an antacid containing only calcium carbonate appears to be largely sufficient.nn
Posologie
By mouth
750 - 3000 mg
Adults
calcium carbonate
Hypocalcemia ✪✪✪✪✪
In cases of mild hypocalcemia, it is sufficient to consume more calcium-rich foods. However, when the calcium level falls below 1.9 mmol/L, in the event of symptomatic acute hypocalcemia, emergency hospitalization is strongly recommended to receive slowly administered intravenous calcium.nnThe recommended daily intake for individuals aged 25 years and over is estimated at 950 mg/day and at 1000 mg/day for young adults (18-24 years), who are still accumulating calcium in their bones.nnFurthermore, for children aged 1 to 3 years, 4 to 10 years and 11 to 17 years, the recommended intakes are respectively 450, 800 and 1150 mg/day. nn
Posologie
By mouth
450 - 1150 mg
Children, Adults, Seniors, Infants
calcium carbonate
Renal insufficiency ✪✪✪✪✪
Oral administration of calcium carbonate or calcium acetate is effective as a phosphate binder, preventing its absorption and thereby reducing hyperphosphatemia associated with renal insufficiency. Calcium citrate is not recommended for this purpose because it increases aluminum absorption and does not bind phosphate as effectively as calcium acetate or calcium carbonate. Calcium acetate or calcium carbonate, 1 to 6.5 g/day in divided doses, usually for 2 to 52 weeks, have been used.
Posologie
Oral
1 - 6.5 g
Adults
calcium carbonate
Benefits and harms of phosphate binders in CKD: a systematic review of randomized controlled trials.
Renal phosphate handling and calcium nephrolithiasis: role of dietary phosphate and phosphate leak.
A comparison of clinically useful phosphorus binders for patients with chronic kidney failure.
Bone health ✪✪✪✪✪
Peak bone growth occurs during adolescence, then bone density in women remains relatively constant until around age 30 to 40. After age 40, bone loss generally occurs at rates of 0.5% to 1% per year. In men, this occurs several decades later. Bone loss is more pronounced if dietary calcium intake is lower than the recommended daily intake. Calcium supplements are widely prescribed to promote bone health, including the treatment and prevention of osteoporosis, a major cause of morbidity and mortality in older adults. Several studies have shown that calcium may be considered a low-potency antiresorptive agent that should be taken in combination with an adequate amount of vitamin D.
Posologie
Oral administration
1000 - 2500 mg
Adults
Calcium carbonate
Synergies
Child development ✪✪✪✪✪
European health authorities (EFSA, European Food Safety Authority and the European Commission) have determined that products containing calcium may claim to contribute to the maintenance of bones and teeth and to the growth and bone development of children only if those products contain at least 120 mg of calcium per 100 g, per 100 ml, or per package if the product contains only one serving. Calcium supplementation in pregnant women who have a low dietary calcium intake (less than 562 mg of elemental calcium per day) increases fetal bone mineralization and bone density. However, in women with an adequate dietary intake, calcium supplementation provides no additional benefit.
Posologie
Oral use
450 - 1150 mg
Children
calcium carbonate
Osteoporosis ✪✪✪✪✪
The most appropriate dose of calcium to reduce the risk of bone fracture is a matter of debate. A population study showed that intake of elemental calcium at 750 mg/day reduced the risk of fractures, but higher doses provided no additional benefit. Furthermore, recommendations published by the U.S. Preventive Services Task Force suggest that taking calcium at daily doses of 1000 mg or less, together with vitamin D at 400 mg or less, is insufficient for the primary prevention of fractures in postmenopausal women. Most experts recommend taking 1000 to 1200 mg per day for the prevention of osteoporosis and/or fractures. It is preferable to split the dose into two, since calcium is better absorbed when taken in doses of 500 mg or less (elemental calcium). Attention should also be paid to the amount of elemental calcium present in each tablet. For example, a 1250 mg tablet of calcium carbonate may contain only 500 mg of elemental calcium. Calcium citrate and calcium carbonate are the two most common forms of calcium supplements. European health authorities (EFSA, the European Food Safety Authority and the European Commission) consider that foods and food supplements providing at least 400 mg of calcium per serving (and ideally at least 15 micrograms of vitamin D) can claim to contribute to reducing the loss of bone mineral density in postmenopausal women aged 50 and over.
Posologie
Oral
1000 - 1200 mg
Seniors
Calcium carbonate, calcium citrate
Synergies
Clinician's Guide to Prevention and Treatment of Osteoporosis.
Dietary calcium intake and risk of fracture and osteoporosis: prospective longitudinal cohort study.
Postmenopausal osteoporosis. Strategies for preventing bone loss, avoiding fracture.
Pregnancy ✪✪✪✪✪
Clinical research shows that a daily oral intake of 1 to 2 g of calcium reduces pregnancy-related hypertension and pre-eclampsia. Calcium appears to reduce the risk of pre-eclampsia by about 50% compared with placebo. An analysis of 19 controlled trials involving more than 29,000 pregnant women found that for every 19 women treated with calcium, one episode of pre-eclampsia would be prevented. The World Health Organization (WHO) recommends prescribing oral calcium supplementation of 1.5 to 2 g per day from the second trimester to high-risk women with low dietary calcium intake to prevent pre-eclampsia.
Posologie
Oral
1 - 2 g
Pregnant women
calcium carbonate
Supplementary calcium in prevention of pre-eclampsia.
WHO recommendations on antenatal care for a positive pregnancy experience
Nutritional interventions for the prevention of maternal morbidity.
Effect of calcium supplementation on pregnancy-induced hypertension and preeclampsia: a meta-analysis of randomized controlled trials.
Calcium supplementation and prevention of pregnancy induced hypertension.
Calcium supplementation in nulliparous women for the prevention of pregnancy-induced hypertension, preeclampsia and preterm birth: an Australian randomized trial. FRACOG and the ACT Study Group.
Premenstrual syndrome ✪✪✪✪✪
In women, calcium levels may be lower during the premenstrual period due to the effects of fluctuations in estrogen levels on the absorption and metabolism of calcium. This can contribute to mood changes and other symptoms associated with premenstrual syndrome (PMS). Calcium has been used at a dose of 1000 to 1336 mg/day for three menstrual cycles. A specific supplement containing 400 mg of calcium and 400 IU of vitamin D taken daily for 3 months has also been used.
Posologie
Oral
1000 - 1336 mg
Adults
calcium carbonate
Synergies
Colorectal cancer ✪✪✪✪✪
Clinical and epidemiological studies have shown that increasing dietary calcium intake or using dietary supplements reduces the risk of colorectal cancer and colonic adenoma. Indeed, a meta-analysis of 10 cohort studies showed a reduced risk of colorectal cancer among people with higher calcium intake. Other clinical trials show that taking calcium supplements of 1.2 to 2 grams per day for 4 years can reduce the risk of recurrent colorectal adenoma by up to 29%. A meta-analysis suggests that daily intake of 1200 mg of calcium reduces the risk of colorectal adenomas in people with a normal BMI (body mass index), but not in those who are overweight or obese. However, results from clinical research regarding the protective effect of calcium against colorectal cancer and adenoma remain contradictory. Vitamin D may be an important factor explaining this contradiction. People with below-average vitamin D levels do not appear to benefit from calcium supplements.
Posologie
Oral
1200 - 2000 mg
Adults
calcium carbonate
Colorectal cancer risk and dietary intake of calcium, vitamin D, and dairy products: a meta-analysis of 26,335 cases from 60 observational studies
Effects of calcium on the incidence of recurrent colorectal adenomas: A systematic review with meta-analysis and trial sequential analysis of randomized controlled trials
Role of supplemental calcium in the recurrence of colorectal adenomas: a metaanalysis of randomized controlled trials
Dietary calcium and vitamin D intake and risk of colorectal cancer: a prospective cohort study in women
Calcium intake and colorectal cancer risk: dose-response meta-analysis of prospective observational studies
Dietary calcium supplementation for preventing colorectal cancer and adenomatous polyps
Calcium supplements for the prevention of colorectal adenomas. Calcium Polyp Prevention Study Group
Dairy foods, calcium, and colorectal cancer: a pooled analysis of 10 cohort studies
Calcium intake and colorectal adenoma risk: dose-response meta-analysis of prospective observational studies
Supplemental calcium in the chemoprevention of colorectal cancer: a systematic review and meta-analysis
Chemoprevention of colorectal cancer: systematic review and economic evaluation
Vitamin D, calcium supplementation, and colorectal adenomas: results of a randomized trial
High blood pressure ✪✪✪✪✪
A study conducted in women over 45 years of age suggests that a higher calcium intake, from both dietary sources and supplements, is associated with a lower risk of developing hypertension compared with women who have a lower calcium intake. Other research carried out in patients with or without hypertension shows that increased dietary calcium intake or calcium supplementation can slightly lower blood pressure. This effect is more pronounced in people whose baseline dietary calcium intake is low.
Posologie
Orally
1000 - 2000 mg
Adults
calcium carbonate
Dietary calcium and blood pressure: a meta-analysis of randomized clinical trials
Effects of dietary calcium supplementation on blood pressure. A meta-analysis of randomized controlled trials
Calcium supplementation for the management of primary hypertension in adults
Calcium from dairy products, vitamin D intake, and blood pressure: the Tromso Study
Blood pressure response to calcium supplementation: a meta-analysis of randomized controlled trials
Effects of calcium supplementation on body weight and blood pressure in normal older women: a randomized controlled trial
The influence of dietary and nondietary calcium supplementation on blood pressure: an updated meta-analysis of randomized controlled trials
Calcium supplementation in patients with essential hypertension: assessment by office, home, and ambulatory blood pressure
Properties
Essential
Bones and teeth contain more than 99% of the calcium in the human body. Calcium is also present in the blood, extracellular fluid, muscles and other tissues. It is essential for nerve transmission, muscle contraction, vascular contraction, vasodilation, glandular secretion, membrane and capillary permeability, enzymatic reactions, respiration, kidney function and blood clotting. It also plays a role in the release and storage of hormones and neurotransmitters, the absorption and binding of amino acids, the absorption of cyanocobalamin (vitamin B12), and the secretion of gastrin (a hormone secreted by G cells of the pyloric mucosa of the stomach). Calcium in bones serves as a reserve pool that can be mobilized to maintain extracellular calcium concentrations.
Usages associés
Digestive effect
Calcium carbonate is an inorganic salt used as an antacid. It is a basic compound that works by neutralizing hydrochloric acid in gastric secretions. Its alkalinizing effect can inhibit the action of pepsin. In addition, calcium is sometimes used in patients with renal insufficiency because it can bind to phosphate in the intestine, preventing its absorption and reducing the hyperphosphatemia associated with renal failure.
Usages associés
Cardiovascular
Evidence suggests that an insufficient dietary intake of calcium may induce the development of hypertension, strokes, and cardiovascular disease. Calcium may lower blood pressure by increasing renal sodium excretion. Animal studies suggest that it may also prevent salt (sodium chloride)-induced hypertension. Furthermore, calcium is a very effective membrane stabilizer in the treatment of rhythm disorders associated with hyperkalemia (elevated potassium levels). However, it has no preventive efficacy and therefore should only be administered when arrhythmia is present. More recently, some population studies suggest that a higher intake of calcium, alone or in combination with vitamin D, is associated with a lower risk of developing type 2 diabetes. The mechanism of action is not fully elucidated. A meta-analysis of clinical research shows that calcium supplementation of 1000 mg or more per day, combined with vitamin D supplementation of 2000 IU or more per day, can reduce fasting blood glucose and insulin resistance in non-diabetic patients.
Usages associés
Bone density
The role of calcium as a treatment remains unclear due to the lack of data in non-deficient individuals. However, this mineral appears likely to suppress biochemical markers of bone resorption only in active, non-sedentary individuals.
Usages associés
Anticancer
A relationship between dairy product consumption and cancer incidence has been established, with evidence of calcium's protective effects that depend on both the type of cancer and the timing of exposure.nnStudies suggest that calcium may have an antiproliferative effect on colorectal cancer cells. Taking calcium alone does not appear to significantly reduce cancer risk. However, the role of calcium in cancer prevention when taken with vitamin D is controversial, as the results remain contradictory. nn
Usages associés
Safe dosage
Adult aged 25 years and older: 950 mg - 2500 mg
Breastfeeding woman aged 25 years and older: 950 mg - 2500 mg
Pregnant woman aged 25 years and older: 950 mg - 2500 mg
Adult aged 18 to 24 years: 1000 mg - 2500 mg
Breastfeeding woman aged 18 to 24 years: 1000 mg - 2500 mg
Child aged 1 to 3 years: 450 mg
Child aged 4 to 10 years: 800 mg
Child aged 11 to 17 years: 1150 mg
Pregnant woman aged 18 to 24 years: 1000 mg - 2500 mg
Interactions
Médicaments
Integrase inhibitors: strong interaction
Calcium appears to decrease levels of integrase inhibitors (dolutegravir, elvitegravir, raltegravir), used for HIV infection, via a chelation mechanism.
Bisphosphonates: moderate interaction
Calcium supplements decrease the absorption of bisphosphonates.
Aluminum: moderate interaction
Calcium citrate can increase aluminum absorption when taken with aluminum hydroxide. Increased aluminum levels can become toxic, particularly in people with kidney disease. However, the effect of calcium citrate on aluminum absorption is due to the citrate anion rather than the calcium cation. Calcium acetate does not appear to increase aluminum absorption.
Levothyroxine: moderate interaction
Calcium reduces the absorption of levothyroxine, probably by forming insoluble complexes. Calcium carbonate supplements reduce the effectiveness of levothyroxine in patients with hypothyroidism.
Lithium: moderate interaction
Clinical evidence suggests that long-term lithium use can cause hypercalcemia in 10% to 60% of patients. Theoretically, concomitant use of lithium and calcium may increase the risk of hypercalcemia.
Quinolones: moderate interaction
When taken orally, calcium can bind to quinolones in the intestine and reduce their absorption.
Sotalol: moderate interaction
Calcium appears to reduce the absorption of sotalol (an antiarrhythmic treatment), probably by forming insoluble complexes.
Calcipotriol: moderate interaction
Calcipotriol, a structural analogue of vitamin D used topically for psoriasis, can be absorbed in sufficient amounts to cause systemic effects, including hypercalcemia. Theoretically, combining calcipotriol with calcium supplements may increase the risk of hypercalcemia.
Anticonvulsants: strong interaction
Phenytoin (Dilantin), fosphenytoin (Cerebyx), phenobarbital, and carbamazepine (Tegretol) reduce calcium absorption by increasing the metabolism of vitamin D, which is necessary for calcium absorption. Calcium and vitamin D supplementation may be necessary, particularly if treatment is prolonged.
Precautions
Hypothyroidism: use with caution
Calcium carbonate reduces the absorption of levothyroxine and decreases its effectiveness in hypothyroid patients receiving treatment.
Hypophosphatemia: use with caution
Calcium supplements should be used with caution in patients with low serum phosphate levels. If calcium intake increases without a simultaneous increase in phosphorus intake, phosphorus absorption may decrease, thereby worsening phosphate deficiency.
