What factors can reduce calcium absorption? How does calcium interact with other nutrients? What are the health benefits of getting enough calcium? Find the answers to these questions and more in our in-depth article.

The Importance of Calcium Absorption

Calcium is the most abundant mineral in the human body, with 99% of it found in the bones and teeth. It plays a crucial role in maintaining strong bones and teeth, as well as the proper functioning of the heart, nerves, muscles, and other bodily systems. Adequate calcium intake is essential, especially for children and older adults, to prevent conditions like osteoporosis and rickets.

Factors That Reduce Calcium Absorption

While calcium is essential for overall health, there are several factors that can impede its absorption in the body. These include:

Age

As we age, our ability to absorb calcium decreases. This is particularly true for older adults, who may need to rely on calcium supplements to meet their daily requirements.

Certain Diseases and Conditions

Conditions like Crohn’s disease, celiac disease, and some intestinal surgeries can affect the body’s ability to absorb calcium properly. People with these conditions may need to take calcium supplements or adjust their diets to ensure they are getting enough of this essential mineral.

Medications

Certain medications, such as corticosteroids, can also interfere with calcium absorption. Individuals taking these medications may need to work closely with their healthcare providers to ensure they are getting the recommended amount of calcium.

Dietary Factors

Consumption of caffeine, alcohol, and carbonated beverages can all impede calcium absorption. Additionally, a diet high in phosphorus or protein may also reduce the body’s ability to absorb calcium effectively.

Enhancing Calcium Absorption

To ensure optimal calcium absorption, it is important to consume a well-balanced diet that includes a variety of calcium-rich foods, such as dairy products, leafy greens, and fortified cereals. Additionally, ensuring adequate intake of other essential nutrients, such as magnesium, phosphorus, and vitamins D and K, can also support the body’s ability to utilize calcium effectively.

Health Benefits of Adequate Calcium Intake

Getting enough calcium has been linked to a range of health benefits, including:

Bone Health

Calcium is essential for the development and maintenance of strong, healthy bones. Adequate calcium intake, particularly in combination with vitamin D, can help prevent osteoporosis and reduce the risk of fractures.

Hypertension and Cardiovascular Health

Some studies suggest that increasing calcium intake may help lower blood pressure slightly, although the evidence is not conclusive. Calcium may also play a role in the prevention of high blood pressure during pregnancy and preeclampsia.

Premenstrual Syndrome (PMS)

Research has shown that women who take calcium supplements may experience a reduction in the severity of their PMS symptoms, including headaches, mood swings, and bloating.

Obesity and Weight Loss

While the relationship between calcium and weight is not fully understood, some studies have found that consuming low-fat dairy products may help with weight loss or maintaining a healthy weight. However, the evidence is mixed, and more research is needed in this area.

Calcium Supplementation

For individuals who are unable to meet their daily calcium requirements through diet alone, calcium supplements may be a useful option. It is important to consult with a healthcare provider to determine the appropriate dosage and type of calcium supplement, as well as to ensure that it does not interact with any other medications or conditions.

Conclusion

Calcium is an essential mineral that plays a crucial role in maintaining overall health, particularly in relation to bone and cardiovascular health. While there are several factors that can impede calcium absorption, understanding these factors and taking steps to enhance calcium intake can help ensure that individuals are meeting their daily calcium requirements and reaping the associated health benefits.

Calcium Information | Mount Sinai

Calcium is the most abundant mineral in your body. It is essential for the development and maintenance of strong bones and teeth, where about 99% of the body’s calcium is found. Calcium also helps the heart, nerves, muscles, and other body systems work properly. It is probably best known for helping prevent osteoporosis.

Your body needs several other nutrients in order for calcium to be absorbed and used properly, including magnesium, phosphorous, and especially vitamins D and K. Many factors, including age, disease states, and medications, can affect calcium absorption. Carbohydrates may enhance calcium absorption while coffee and cigarette smoke may impede it.

The best way to get calcium is through food. Many foods are fortified with calcium. But some people may need to take calcium supplements to get the recommended amount. It is especially important for children to get enough calcium in their diets as they are growing and forming bone, and for older people as they start to lose bone.

Postmenopausal women, people who consume large amounts of caffeine, alcohol, or soda, and those who take corticosteroid medications may need calcium supplements. Calcium deficiency can be found in people who don’t absorb enough calcium, as can happen with Crohn’s disease, celiac disease, and some intestinal surgeries.

Getting enough calcium may help prevent or treat the following conditions:

Osteoporosis

Your body needs calcium to build and maintain healthy bones and strong teeth. People start to lose more bone than their bodies make in their 30s, and the process speeds up as they get older. Studies have shown that calcium, particularly in combination with vitamin D, may help prevent bone loss associated with menopause. It may also help prevent bone loss in older men. If you do not get enough calcium in your diet, your doctor may recommend a supplement.

Hypoparathyroidism

People with this condition have underactive parathyroid glands. These four small glands sit on the four corners of the thyroid in the neck and produce a hormone that regulates calcium, phosphorous, and vitamin D levels in the body. People with this condition should follow a high-calcium, low-phosphorous diet as prescribed by their doctors. Often, they will also need to take calcium supplements.

Premenstrual Syndrome (PMS)

One large, well-designed study showed that women who took 1,200 mg of calcium per day reduced their symptoms of PMS by 50%, including headache, moodiness, food cravings, and bloating. A smaller study suggested that calcium may help reduce menstrual pain.

High Blood Pressure

People who do not get enough calcium may be at higher risk for hypertension or high blood pressure. Some studies suggest that increasing calcium levels may lower blood pressure slightly. However, not all studies have been positive. Researchers aren’t sure whether calcium supplements would have any benefit, or whether it’s the effects of a diet that includes low-fat dairy products (which contain calcium) that is responsible.

If you want to try calcium supplements, do not stop taking your blood pressure medication. Instead, talk to your doctor about the right amount of calcium for you. You may need to take calcium for 6 to 8 weeks before you see any improvement in blood pressure.

Some studies suggest that calcium supplements may play a role in the prevention of high blood pressure during pregnancy and preeclampsia, a combination of high blood pressure, fluid retention, and high levels of protein in the urine that some women develop during the last trimester of pregnancy. However, not all studies show the same benefit. Taking a prenatal vitamin, with magnesium, folic acid, and many other nutrients, and getting enough calcium in food, may lower the risk of developing high blood pressure during pregnancy.

Obesity and Weight Loss

Animal and human studies have found that eating low-fat dairy products may help you lose weight or stay at a healthy weight. However, researchers aren’t sure whether the calcium in the dairy products affects weight, or whether it’s some other nutrient — or even a combination of nutrients. In addition, not all studies have been positive. Plus there’s no sound evidence that taking calcium supplements, as opposed to eating low-fat dairy products, would help with weight loss. More research is needed.

High Cholesterol

Preliminary studies in animals and people suggest that calcium supplements, in the range of 1,500 to 2,000 mg per day, may help lower cholesterol slightly. From these studies, it seems that calcium supplements, along with exercise and a healthy diet, may be better at keeping cholesterol at normal levels than at lowering already high cholesterol. More research is needed.

Rickets

Rickets causes softening and weakening of the bone in children. Although very rare in North America and Western Europe, where children drink a lot of milk, it still happens in many parts of the world. Researchers thought rickets was caused by a vitamin D deficiency. But studies suggest that taking calcium supplements is an effective treatment.

Other Uses

Stroke. In a population-based study, in which large groups of people were followed over time, women who took in more calcium, both through food and supplements, were less likely to have a stroke over a 14-year period. More research is needed.

Colon Cancer. Although not all studies agree, some show that people who have higher amounts of calcium, vitamin D, and milk in their diets are less likely to develop colorectal cancer than those who have low amounts. Researchers are not sure whether calcium supplements would have the same effect, or even whether calcium itself is making the difference.

Dietary Sources

The richest food sources of calcium include:

• Cheeses, such as Parmesan, Romano, gruyere, cheddar, American, mozzarella, and feta
• Low-fat dairy products, such as milk and yogurt
• Tofu
• Blackstrap molasses

Other good sources of calcium include:

• Almonds
• Brewer’s yeast
• Bok choy
• Brazil nuts
• Broccoli
• Cabbage
• Dried figs
• Kelp
• Dark leafy greens (such as dandelion, turnip, collard, mustard, kale, and Swiss chard)
• Hazelnuts
• Oysters
• Sardines
• Canned salmon

Foods that are fortified with calcium — such as juices, soy milk, rice milk, tofu and cereals — are also good sources of this mineral.

Available Forms

There are many forms of calcium available as dietary supplements. They differ in the amount of calcium they contain, how well the body absorbs them, and how much they cost. The two most popular forms are calcium citrate and calcium carbonate.

• Calcium citrate. Easily absorbed and digested by the body. It does not contain as much elemental calcium — the amount your body actually absorbs — as calcium carbonate. It is more expensive than calcium carbonate. Also, calcium citrate should not be used with aluminum-containing antacids.
• Calcium carbonate. Less expensive than calcium citrate and contains more elemental calcium. Requires a certain amount of stomach acid to be absorbed. So it is usually taken with a glass of orange juice. Many antacids contain calcium carbonate.

Avoid calcium supplements that are derived from oyster shells, dolomite, and bone meal as they may contain lead, a toxic metal that can harm the brain and kidneys, cause anemia, and raise blood pressure.

How to Take It

Calcium supplements should be taken in small doses (no more than 500 mg at a time) during the day with 6 to 8 cups of water to avoid constipation.

The following are daily dietary recommendations from the Institute of Medicine.

Pediatric

Talk to your pediatrician before giving a child any nutritional supplement, including calcium.

• Birth to 6 months: 200 mg
• 7 months to 1 year: 260 mg
• 1 to 3 years: 700 mg
• 4 to 8 years: 1000 mg
• 9 to 18 years: 1,300 mg

Adult

• 19 to 50 years: 1,000 mg
• Women 51 years and older: 1,200 mg
• Men 51 to 70 years: 1,000 mg
• Men older than 70: 1,200 mg
• Pregnant and breastfeeding women under 19 years: 1,300 mg
• Pregnant and breastfeeding women 19 years and older: 1,000 mg

For prevention of colon cancer, some researchers recommend 1,800 mg per day. Speak with your doctor to determine the right dose for you.

Precautions

Take dietary supplements only under the supervision of a knowledgeable health care provider since there is a potential for side effects. Total calcium intake, from combined dietary and supplemental sources, should not exceed 2,500 mg per day.

Side effects can include constipation and stomach upset. Very high doses can cause:

• Nausea and vomiting
• Loss of appetite
• Increased urination
• Kidney damage
• Confusion
• Irregular heart rhythm

People with hyperparathyroidism, kidney failure, sarcoidosis, or cancer could be at risk for high levels of calcium and should not take calcium supplements.

People with a history of kidney stones should not take calcium supplements. However, some research suggests that calcium in foods may not increase the risk of kidney stones. If you have or have had kidney stones, talk to your doctor about whether you should limit calcium in your diet.

Some population studies suggest that getting high amounts (more than 2,000 mg per day) of calcium through the diet may increase the risk of prostate cancer. Two of these studies found that low-fat and nonfat milk — but not other dairy foods — was associated with a higher risk of advanced prostate cancer. But these studies don’t prove that drinking low-fat or nonfat milk causes an increased risk of prostate cancer. And some research suggests that the amount of calcium in the diet isn’t associated with prostate cancer risk. If you have prostate cancer, or are concerned about dairy products and prostate cancer risk, talk to your doctor.

The Institute of Medicine sets the tolerable upper level of daily calcium intake at 2,500 mg. Some studies have suggested that getting amounts higher than 1,000 to 1,200 mg/day may be associated with an increased risk of heart attack. More research is needed.

When figuring out how much calcium you need, be sure to take into account the calcium-rich foods you eat — such as cheese, yogurt, milk — along with any supplements.

Possible Interactions

If you are being treated with any of the following medications, you should not use calcium supplements without talking to your doctor first.

Ceftriaxone (Rocephin)

These medications may have potentially fatal interactions with calcium.

Biphosphates

These medications are used to treat osteoporosis and some other bone conditions. Calcium may interfere with how your body absorbs them. Calcium-containing products should be taken at least 2 hours before or after bisphosphonates. Bisphosphonates include:

• Alendronate (Fosamax)
• Etidronate (Didronel)
• Ibandronate (Boniva)
• Risedronate (Actonel)
• Tiludronate (Skelid)
• Zoledronic acid (Reclast)

Antacids that contain aluminum

When calcium citrate is taken with these antacids, the amount of aluminum absorbed into the blood may go up. For people with kidney disease, the aluminum levels could be toxic.

Blood pressure medications

Taking calcium with a beta-blocker may interfere with blood levels of both the calcium and the beta-blocker. Study results aren’t clear, however. It also has been reported that calcium interferes with calcium channel blockers. But these study results are also mixed. If you take a beta-blocker or calcium-channel blocker, do not take calcium supplements without your doctor’s supervision. Beta-blockers include atenolol (Tenormin), metoprolol (Lopressor, Toprol-XL), and propranolol (Inderal, Inderal LA), among others. Calcium-channel blockers include amlodipine (Norvasc), diltiazem (Cardizem), and nifedipine (Procardia).

Cholesterol-lowering medications

A type of medication known as bile acid sequestrants, used to treat high cholesterol, may interfere with calcium absorption and raise the amount of calcium that leaves the body in urine. Your doctor may recommend taking calcium and vitamin D supplements. These drugs include cholestyramine (Questran), colestipol (Colestid), colesevelam (Welchol).

Calcipotriene (Dovenex)

Taking calcium supplements while using calcipotriene, a topical medication for psoriasis, could increase the risk of having calcium levels that are too high (hypercalcemia).

Corticosteroids (prednisone)

If you take corticosteroids on a long-term basis, you may need to take calcium supplements.

Digoxin

High levels of calcium may raise the risk of a toxic reaction to digoxin, a medication used to treat irregular heart rhythms. On the other hand, low levels of calcium keep digoxin from working. If you take digoxin, your doctor should monitor your calcium levels closely.

Diuretics (water pills)

Different types of diuretics interact with calcium in opposite ways:

• Thiazide diuretics can raise calcium levels in the blood. These drugs include chlorothiazide (Diuril), hydrochlorothiazide, ghlorthalidone (Hygroton), indapamide (Lozol), metolozone (Zaroxolyn), and polythiazide (Renese), among others.
• Loop diuretics can decrease calcium levels. These drugs include furosemide (Lasix) and bumetanide (Bumex).
• Amiloride (Midamor) is a type of diuretic called a potassium-sparing diuretic. It may reduce the amount of calcium your body eliminates in urine, and raise calcium levels in the blood, especially in people with kidney stones.

Estrogens

Estrogens may contribute to an overall increase in calcium blood levels. Taking calcium supplements with estrogens improves bone density.

Gentamicin

Taking calcium during treatment with the antibiotic gentamicin may increase the potential for toxic effects on the kidneys.

Sotalol (Betapace)

Sotalol is used to treat an irregular heartbeat. Calcium may decrease how much sotalol is absorbed by the body.

Thyroid hormone

Calcium can decrease the amount of thyroid hormone medication that your body absorbs.

Antibiotics

Different types of antibiotics interact with calcium:

• Quinolones. Calcium can interfere with the body’s ability to absorb quinolone antibiotics. These drugs include ciprofloxacin (Cipro), levofloxacin (Levaquin), norfloxacin (Noroxin), and ofloxacin (Floxin). Take calcium supplements 2 to 4 hours before or after taking quinolone antibiotics.
• Tetracyclines. Calcium can interfere with the body’s ability to absorb tetracycline antibiotics, including doxycycline, minocycline, and tetracycline. Take calcium supplements 2 to 4 hours before or after taking tetracycline antibiotics.

Anti seizure medications

Some seizure medications, such as phenytoin (Dilantin), carbamazepine (Tegretol), phenobarbitol, and primidone (Mysoline), may lower levels of calcium in the body. Some doctors recommend taking vitamin D along with anti seizure drugs to keep calcium levels up. Take doses of calcium and anti seizure medications at least 2 hours apart because each interferes with the absorption of the other.

Supporting Research

Aloia JF, Dhaliwal R, Shieh A, Mikhail M, Islam S, Yeh JK. Calcium and vitamin d supplementation in postmenopausal women. J Clin Endocrinol Metab. 2013;98(11):E1702-E1709.

Avgerinos DV, Leitman IM, Martinez RE, Liao EP. Evaluation of markers for calcium homeostasis in a population of obese adults undergoing gastric bypass operations. J Am Coll Surg. 2007;205(2):294-297.

Barrett-Connor E, Wade SW, Downss RW, et al. Self-reported calcium use in a cohort of postmenopausal women receiving osteoporosis therapy: results from POSSIBLE US. Osteoporosis Int. 2015;26(8):2175-2184.

Bauman WA, Shaw S, Jayatilleke E, Spungen AM, Herbert V. Increased intake of calcium reverses vitamin B12 malabsorption induced by metformin. Diabetes Care. 2000;23(9):1227-1231.

Bendich A. The potential for dietary supplements to reduce premenstrual syndrome (PMS) symptoms [review]. J Am Coll Nutr. 2000;19(1):3-12.

Bonithon-Kopp C, Kronborg O, Giacosa A, Rath U, Faivre J. Calcium and fibre supplementation in prevention of colorectal adenoma recurrence: a randomised intervention trial. European Cancer Prevention Organisation Study Group. Lancet. 2000;356(9238):1300-1306.

Boonen S, Lips P, Bouillon R, Bischoff-Ferrari HA, Vanderschueren D, Haentjens P. Need for additional calcium to reduce the risk of hip fracture with vitamin d supplementation: evidence from a comparative metaanalysis of randomized controlled trials. J Clin Endocrinol Metab. 2007;92(4):1415-1423.

Borghi L, Schianchi T, Meschi T, et al. Comparison of two diets for the prevention of recurrent stones in idiopathic hypercalciuria. N Engl J Med. 2002;346(2):77-84.

Bostick RM, Fosdick L, Grandits GA, Grambsch P, Gross M, Louis TA. Effect of calcium supplementation on serum cholesterol and blood pressure. Arch Fam Med. 2000;9(1):31-38.

Caan B, Neuhouser M, Aragaki A, Lewis CB, Jackson R, LeBoff MS, et al. Calcium plus vitamin D supplementation and the risk of postmenopausal weight gain. Arch Intern Med. 2007;167(9):893-902.

Chan JM, Stampfer MJ, Ma J, Gann PH, Gaziano JM, Giovannucci EL. Dairy products, calcium, and prostate cancer risk in the Physicians’ Health Study. Am J Clin Nutr. 2001;74(4):549-554.

Chen Y, Strasser S, Cao Y, Wang KS, Zheng S. Calcium intake and hypertension among obese adults in United States: associations and implications explored. J Hum Hypertens. 2015;29(9):541-547.

Consensus Opinion. The role of calcium in peri- and postmenopausal women: consensus opinion of the North American Menopause Society. Menopause. 2001;8(2):84-95.

Dagnelie PC, Schuurman AG, Goldbohm RA, Van den Brandt PA. Diet, anthropometric measures and prostate cancer risk: a review of prospective cohort and intervention studies. BJU Int. 2004;93(8):1139-1150.

Davies KM, Heaney RP, Recker RR, et al. Calcium intake and body weight. J Clin Endocrinol Metab. 2000;85(12):4635-4638.

Emkey R, Emkey G. Calcium metabolism and correcting calcium deficiencies. Endocrinology and Metabolism Clinics. 2012;41(3):527-556.

Giovannucci E, Liu Y, Stampfer MJ, Willett WC. A prospective study of calcium intake and incident and fatal prostate cancer. Cancer Epidemiol Biomarkers Prev. 2006;15(2):203-210.

Gonnelli S, Campagna MS, Montagnani A, et al. Calcium bioavailability from a new calcium-fortified orange beverage, compared with milk in healthy volunteers. Int J Vitam Nutr Res. 2007;77(4):249-254.

Grau MV, Baron JA, Sandler RS, et al. Prolonged effect of calcium supplementation on risk of colorectal adenomas in a randomized trial. J Natl Cancer Inst. 2007;99(2):129-136.

Gulson BL, Mizon KJ, Palmer Jm, Korsch MJ, Taylor AJ. Contribution of lead from calcium supplements to blood lead. Environ Health Perspect. 2001;109(3):283-288.

Heaney RP, Dowell SD, Bierman J, Hale CA, Bendich A. Absorbability and cost effectiveness in calcium supplementation. J Am Coll Nutr. 2001;20(3):239-246.

Hermensen K. Diet, blood pressure and hypertension. Br J Nutr. 2000;83(Suppl 1):S113-S119.

Hiller JE, Crowther CA, Moore VA, Willson K, Robinson JS. Calcium supplementation in pregnancy and its impact on blood pressure in children and women: follow up of a randomised controlled trial. Aust N Z J Obstet Gynaecol. 2007;47(2):115-121.

Hofmeyr G, Duley L, Atallah A. Dietary calcium supplementation for prevention of pre-eclampsia and related problems: a systematic review and commentary. BJOG. 2007;114(8):933-943.

Jänne PA, Mayer RJ. Chemoprevention of colorectal cancer. N Engl J Med. 2000;342(26):1960-1968.

Kampman E, Slattery ML, Caan B, Potter JD. Calcium, vitamin D, sunshine exposure, dairy products and colon cancer risk (United States). Cancer Causes Control. 2000:11(5):459-466.

Krall EA, Wehler C, Garcia RI, et al. Calcium and vitamin D supplements reduce tooth loss in the elderly. Am J Med. 2001;111(6):452-456.

Krauss RM, Eckel RH, Howard B, et al. AHA dietary guidelines. Revision 2000: A statement for healthcare professionals from the Nutrition Committee of the American Heart Association. Circulation. 2000;102(18):2284-2299.

Lappe JM, Travers-Gustafson D, Davies KM, Recker RR, Heaney RP. Vitamin D and calcium supplementation reduces cancer risk: results of a randomized trial. Am J Clin Nutr. 2007;85(6):1586-1591.

Larsson SC, Orsini N, Wolk A. Dietary calcium intake and risk of stroke: a dose-response meta-analysis. Am J Clin Nutr. 2013;97(5):951-957.

Lin Y-C, Lyle RM, McCabe LD, et al. Dairy calcium is related to changes in body composition during a two-year exercise intervention in young women. J Am Coll Nutr. 2000;19(6):754-760.

Martin BR, Davis S, Campbell WW, Weaver CM. Exercise and calcium supplementation: effects on calcium homeostasis in sportswomen. Med Sci Sports Exerc. 2007;39(9):1481-1486.

Myers VH, Champagne CM. Nutritional effects on blood pressure. Curr Opin Lipidol. 2007;18(1):20-24.

Nakamura K, Saito T, Kobayashi R, et al. Effect of low-dose calcium supplements on bone loss in perimenopausal and postmenopausal Asian women: a reandomized controlled trial. J Bone Miner Res. 2012;27(11):2264-2270.

NAMS Consensus. Consensus Opinion: the role of calcium in peri-and postmenopausal women: consensus opinion of The North American Menopause Society. Menopause. 2001;8(20):84-95.

Napoli N, Thompson J, Civitelli R, Armamento-Villareal RC. Effects of dietary calcium compared with calcium supplements on estrogen metabolism and bone mineral density. Am J Clin Nutr. 2007;85(5):1428-1433.

NIH Consensus Development Panel. Osteoporosis prevention, diagnosis, and therapy. JAMA. 2001;285(6):785-795.

Ochner CN, Lowe MR. Self-reported changes in dietary calcium and energy intake predict weight regain following a weight loss diet in obese women. J Nutr. 2007;137(10):2324-2328.

Palacios C, Benedetti P, Fonseca S. Impact of calcium intake on body mass index in Venezuelan adolescents. P R Health Sci J. 2007;26(3):199-204.

Park SY, Murphy SP, Wilkens LR, Stram DO, Henderson BE, Kolonel LN. Calcium,vitamin D, and dairy product intake and prostate cancer risk: the Multiethnic Cohort Study. Am J Epidemiol. 2007;166(11):1259-1269.

Park Y, Leitzmann MF, Subar AF, Hollenbeck A, Schatzkin A. Dairy food, calcium, and risk of cancer in the NIH-AARP Diet and Health Study. Arch Intern Med. 2009;169(4):391-401.

Park Y, Mitrou PN, Kipnis V, Hollenbeck A, Schatzkin A, Leitzmann MF. Calcium, dairy foods, and risk of incident and fatal prostate cancer: the NIH-AARP Diet and Health Study. Am J Epidemiol. 2007;166(11):1270-1279.

Peacock M, Liu G, Carey M, et al. Effect of calcium or 25OH vitamin D3 supplementation on bone loss at the hip in men and women over the age of 60. J Clin Endocrinol Metabol. 2000;85(9):3011-3019.

Petti S, Cairella G, Tarsitani G. Nutritional variables related to gingival health in adolescent girls. Community Dent Oral Epidemiol. 2000;28(6):407-413.

Ross EA, Szabo NJ, Tebbett IR. Lead content of calcium supplements. JAMA. 2000;284(11):1425-1429.

Sacks FM, Svetkey LP, Volmer WM, et al. Effects on blood pressure of reduced dietary sodium and the Dietary Approaches to Stop Hypertension (DASH) Diet. N Engl J Med. 2001;344(1):3-10.

Shahar DR, Schwarzfuchs D, Fraser D, et al. Dairy calcium intake, serum vitamin D, and successful weight loss. Am J Clin Nutr. 2010;92(5):1017-1022.

Shin CS, Kim KM. Calcium, Is It Better to Have Less? J Cell Biochem. 2015;116(8):1513-1521.

Straub DA. Calcium supplementation in clinical practice: a review of forms, doses, and indications. Nutr Clin Pract. 2007;22(3):286-296.

Tang BM, Eslick GD, Nowson C, Smith C, Bensoussan A. Use of calcium or calcium in combination with vitamin D supplementation to prevent fractures and bone loss in people aged 50 years and older: a meta-analysis. Lancet. 2007;370(9588):657-666.

Tavani A, Bertuccio P, Bosetti C, et al. Dietary intake of calcium, vitamin D, phosphorus and the risk of prostate cancer. Eur Urol. 2005;48(1):27-33.

Thys-Jacobs S. Micronutrients and the premenstrual syndrome: the case for calcium. J Am Coll Nutr. 2000;19(2):220-227.

Torkos S. Drug-nutrient interactions: a focus on cholesterol-lowering agents. Int J Integrative Med. 2000;2(3):9-13.

Varenna M, Binelli L, Casari S, Zucchi F, Sinigaglia L. Effects of dietary calcium intake on body weight and prevalence of osteoporosis in early postmenopausal women. Am J Clin Nutr. 2007;86(3):639-644.

Wagner G, Kindrick S, Hertzler S, DiSilvestro RA. Effects of various forms of calcium on body weight and bone turnover markers in women participating in a weight loss program. J Am Coll Nutr. 2007;26(5):456-461.

Zemel MB, Shi H, Greer B, Dirienzo D, Zemel PC. Regulation of adiposity by dietary calcium. FASEB. 2000;14(9):1132-1138.

Did you know that certain foods block calcium absorption?

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You try to eat a healthy, calcium-rich diet. You watch your weight. You exercise. You do everything in your power to maintain strong bones because you want to be active well into your 70s and 80s.

You even make sure you have a nutritious breakfast of natural whole wheat squares topped cold, vitamin-D-fortified milk.

It sounds like a nutritious way to your day. But eating whole-wheat cereal and milk together may not be the best menu choice if you are trying to increase your bone mass. There are certain foods, like wheat, that block calcium absorption.

Phytates bind calcium.

High-fiber foods contain phytates, which prevent the body from absorbing calcium in other foods. Eating a high-fiber, whole-wheat cereal with milk, macaroni and cheese, or drinking a tall, cold glass of milk with Boston baked beans and hot dogs may be great-tasting combinations, but they do not boost bone-building nutrition.

Phytates found in whole-grains, legumes (dried beans), nuts and soy products bind the calcium of other foods eaten when they are eaten at the same time. When calcium is bound, the body cannot use it.

Oxalic acid hinders calcium absorption.

Foods high in oxalic acid also impede the absorption of calcium by binding the mineral.

Spinach is naturally high in calcium, but it is also high in oxalic acid. The body is unable to process the calcium it provides. Other foods that contain oxalic acid include beet greens, rhubarb and sweet potatoes.

Though these foods should not be considered for their calcium value, they do provide other nutrients and minerals that help the body stay healthy.

Does protein interfere with calcium absorption?

Historically, nutritionists have warned that eating large amounts of protein causes the kidneys to flush calcium out of the body. But recent studies show protein also may increase intestinal calcium absorption.

More study is needed to determine protein’s effect on the body’s ability to process calcium. To make the most of your calcium intake, don’t drink milk with your beef stew, chili or steak dinner. Eat your meal and then drink your milk later.

Beer, cheese and snacks are a trifecta for calcium loss.

Alcohol and salty foods are catalysts for calcium flushing. As calcium levels in the blood decrease, the body extracts (resorbing) calcium from the bones to obtain the calcium it needs to function properly. Calcium flushing can make the bones porous, which can lead to the development of osteoporosis.

To minimize calcium flushing:

• Avoid eating foods that have a sodium content higher than 20 percent of the daily recommended value.
• Don’t drink more than two or three alcoholic drinks a day.

You can eat your spinach and build your calcium, too.

Wheat and other “bad-to-the-bone” foods provide many other vitamins and minerals vital to your health. You should still eat these types of foods, just not at the same time that you drink milk or eat calcium-rich foods.

The best way to maximize the nutrition from foods that bind or flush calcium and continue to boost your calcium levels is just a matter of scheduling. Eat calcium-binding foods at least two hours before or after you eat calcium-rich foods. This timing allows your body to maximize the vitamins and minerals of all food types. By making this timely adjustment to your meals, you gain all the nutritional benefits without interfering with your body’s ability to absorb the calcium it needs every day.

Source:
The National Institutes of Health Office of Dietary Supplements

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Calcium in daily urine

General information about the study

Every day we lose part of the calcium after it is filtered by the kidneys and excreted in the urine. This analysis allows you to determine such daily loss of calcium through the kidneys.

Calcium is a cation that is absorbed into the general circulation from food. It is involved in bone formation, nerve impulse transmission, muscle contraction and blood clotting. Calcium is found in the bones, circulates in the blood, is filtered by the kidneys, and is mostly reabsorbed at normal levels in the blood. With an increase in the concentration of serum calcium, the kidneys slow down the processes of reverse reabsorption, due to this, the level of calcium in the urine increases.

The balance of calcium excretion and absorption is closely related to phosphate (phosphates are salts of phosphoric acid). With an increase in the concentration of calcium in the blood, the level of phosphate decreases, when the content of phosphate increases, the proportion of calcium decreases.

Mechanisms of phosphorus-calcium metabolism:

• parathyroid glands at high phosphate levels (at low calcium levels) secrete parathormone, which stimulates osteoclasts, which destroy bone tissue, thereby increasing the concentration of calcium in the blood;
• When calcium levels in the blood are high, the thyroid gland secretes calcitonin, which causes calcium to move from the blood to the bones;
• The parathyroid glands also activate vitamin D, increasing calcium absorption in the gastrointestinal tract and cation reabsorption in the kidneys.

Urinary calcium is needed to assess calcium intake and/or the balance between calcium absorption, bone resorption and calcium excretion through the kidneys.

What is research used for?

• To determine the amount of calcium consumed and its absorption in the intestine.
• To find the cause of bone calcium loss (osteoporosis).
• For the diagnosis of kidney disease.
• To assess the functions of the parathyroid glands.

When is the test ordered?

• Calcium in the urine, unlike all other indicators of the composition of urine, is rarely studied.
• In the diagnosis of diseases of the parathyroid glands and familial hypocalciuric hypercalcemia (insufficient excretion of calcium in the urine due to a violation of the intrarenal mechanism).
• With symptoms of urolithiasis: sharp and acute pain in the right or left lumbar region, the spread of this pain below and somewhat to the lateral areas of the abdomen, impaired urination, and the appearance of blood in the urine (this symptom alone is enough).
• In the diagnosis of digestive disorders that may affect the small intestine, where the absorption of essential nutrients occurs (together with other tests).

Description of article

General information about the study
What is research used for?
When is the study scheduled?

Daily urine calcium

Calcium is one of the main intracellular cations found mainly in bone tissue. Physiologically, it is active only in the ionized form, in which it is present in large quantities in the blood plasma.

Russian synonyms

Calcium ions.

Synonyms English

Urine Calcium (Ca), Quantitative (24-Hour), Urinary Ca ²⁺ .

Test method

Colorimetric photometric method.

Units

mmol/day (millimoles per day).

What biomaterial can be used for research?

Daily urine.

How to properly prepare for the study?

1. Eliminate alcohol from the diet 24 hours before the test.
2. Do not take diuretics within 48 hours prior to urine collection (on agreement with the doctor).

General information about the study

Every day we lose some calcium after it is filtered by the kidneys and excreted in the urine. This analysis allows you to determine such daily loss of calcium through the kidneys.

Calcium is a cation that is absorbed into the general circulation from food. It is involved in bone formation, nerve impulse transmission, muscle contraction and blood clotting. Calcium is found in the bones, circulates in the blood, is filtered by the kidneys, and is mostly reabsorbed at normal levels in the blood. With an increase in the concentration of serum calcium, the kidneys slow down the processes of reverse reabsorption, due to this, the level of calcium in the urine increases.

The balance of excretion and absorption of calcium is closely related to phosphate (phosphates are salts of phosphoric acid). With an increase in the concentration of calcium in the blood, the level of phosphate decreases, when the content of phosphate increases, the proportion of calcium decreases.

Mechanisms of phosphorus-calcium metabolism:

• parathyroid glands at high phosphate levels (at low calcium levels) secrete parathormone, which stimulates osteoclasts, which destroy bone tissue, thereby increasing the concentration of calcium in the blood;
• When calcium levels in the blood are high, the thyroid gland secretes calcitonin, which causes calcium to move from the blood to the bones;
• The parathyroid glands also activate vitamin D, increasing calcium absorption in the gastrointestinal tract and cation reabsorption in the kidneys.

Urinary calcium is needed to assess calcium intake and/or the balance between calcium absorption, bone resorption and calcium excretion through the kidneys.

What is research used for?

• To determine the amount of calcium consumed and its absorption in the intestine.
• To find the cause of bone calcium loss (osteoporosis).
• For the diagnosis of kidney disease.
• To assess the functions of the parathyroid glands.

When is the test ordered?

• Calcium in the urine, unlike all other indicators of the composition of urine, is rarely studied.
• In the diagnosis of diseases of the parathyroid glands and familial hypocalciuric hypercalcemia (insufficient excretion of calcium in the urine due to a violation of the intrarenal mechanism).
• With symptoms of urolithiasis: sharp and acute pain in the right or left lumbar region, the spread of this pain below and somewhat to the lateral areas of the abdomen, impaired urination, and the appearance of blood in the urine (this symptom alone is enough).
• In the diagnosis of digestive disorders that may affect the small intestine, where the absorption of essential nutrients occurs (together with other tests).

What do the results mean?

Reference values ​​

Causes of elevated daily urine calcium levels:

• metastases of many neoplasms (in combination with elevated blood calcium levels),
• nephrolithiasis or nephrocalcinosis, especially with hyperproteinemia,
• urolithiasis,
• hyperparathyroidism,
• malignant neoplasms with metastases, multiple myeloma (some tumors secrete a substance similar in effect to parathormone),
• Paget’s disease,
• vitamin D excess,
• idiopathic hypercalciuria (decreased calcium reabsorption in the kidneys),
• Fanconi syndrome (decreased tubular calcium reabsorption due to a defect in tubular development),
• Sarcoidosis.

Causes of low daily urine calcium levels:

• hypoparathyroidism, pseudohypoparathyroidism,
• pre-eclampsia (a disease of pregnancy accompanied by high blood pressure, edema and increased excretion of protein in the urine),
• kidney diseases (filtering disorders),
• vitamin D deficiency,
• familial hypocalciuric hypercalcemia,
• digestive disorders (celiac disease, sprue – malabsorption of food due to diseases of the small intestine, – pancreatitis, alcoholism).

What can influence the result?

• Factors that can distort the result of this analysis:
  • calcium or vitamin D in any form before passing urine (preparations of these substances, milk),
  • single urine sample (must be sampled from all urine collected within 24 hours to avoid false low results),
  • long-term immobilization (immobilization of limbs after fractures), long bed rest,
  • high urinary phosphorus (may underestimate results),
  • insolation (exposure to solar radiation).
• Antacids, antiepileptics, carbonic anhydrase inhibitors, loop diuretics, amiloride, asparaginase, cholestyramine, ergocalciferol, spironolactone increase urinary calcium concentration.
• Reduce the level of calcium in the urine glucocorticoids, thiazide diuretics, oral contraceptives, estrogens, acetylsalicylic acid, indomethacin, anabolic steroids, calcitriol, cholestyramine, vitamins A, K, C, lithium salts, neomycin.

Important notes

• Urinary calcium levels are often quite high in patients with stones in any organ.
• Calcium concentration decreases in the II-III trimester of pregnancy.
• Although urinary calcium levels are elevated in 30% to 80% of patients with primary hyperparathyroidism, this is still not a diagnostic finding.

Also recommended

• Serum calcium
• Calcium, ionized
• Sulkovich test
• Albumin in urine (microalbuminuria)
• Serum magnesium
• Serum albumin
• Total protein in whey
• Vitamin D, 25-hydroxy (calciferol)
• Serum calcitonin
• Thyroid Stimulating Hormone (TSH)
• Thyroxine free (T4 free)
• General thyroxine (T4)
• Triiodothyronine total (T3)
• Triiodothyronine free (T3 free)
• Parathyroid hormone, intact

Who orders the examination?

Therapist, nephrologist, endocrinologist, gastroenterologist, nutritionist, traumatologist.