Vitamin d helps absorb calcium. Calcium and Vitamin D: Essential Nutrients for Skeletal and Extraskeletal Health
How does vitamin D help absorb calcium. What are the effects of vitamin D deficiency on bone health. Can vitamin D supplementation prevent osteoporotic fractures. What is the prevalence of vitamin D inadequacy in different populations.
The Crucial Role of Vitamin D in Calcium Absorption
Vitamin D plays a pivotal role in calcium absorption, making it an essential nutrient for maintaining strong bones and overall health. But how exactly does vitamin D facilitate calcium absorption?
The process begins in the small intestine, where vitamin D enhances the efficiency of calcium absorption. Specifically, vitamin D promotes the expression of calcium transport proteins in the intestinal cells. These proteins, such as TRPV6, act as channels that allow calcium to move from the intestinal lumen into the bloodstream.
Research by Walters et al. (2006) demonstrated that vitamin D regulates the expression of calcium transport proteins in the human duodenum. This regulation is crucial for maintaining optimal calcium levels in the body, especially as we age.
Age-Related Changes in Calcium Absorption
Interestingly, the relationship between vitamin D and calcium absorption changes as we get older. A study by Pattanaungkul et al. (2000) revealed that elderly women exhibit intestinal resistance to the action of 1,25-dihydroxyvitamin D, the active form of vitamin D. This resistance can lead to decreased calcium absorption in older individuals, highlighting the importance of maintaining adequate vitamin D levels throughout life.
Vitamin D Deficiency: A Global Health Concern
Vitamin D deficiency has become a widespread issue, affecting populations worldwide. But what are the consequences of this deficiency, particularly on bone health?
Insufficient vitamin D levels can lead to various skeletal problems, including:
- Reduced calcium absorption
- Increased bone turnover
- Decreased bone mineral density
- Increased risk of fractures
A comprehensive review by Holick (2007) in the New England Journal of Medicine emphasized the far-reaching effects of vitamin D deficiency on skeletal health. The review highlighted that chronic vitamin D deficiency can result in osteomalacia, a condition characterized by softening of the bones due to impaired mineralization.
Prevalence of Vitamin D Inadequacy
The prevalence of vitamin D inadequacy varies across different populations and geographic regions. A study by van der Wielen et al. (1995) found that serum vitamin D concentrations were particularly low among elderly people in Europe, especially during winter months.
In North America, a study by Holick et al. revealed a high prevalence of vitamin D inadequacy among postmenopausal women receiving osteoporosis treatment. This finding underscores the importance of addressing vitamin D status in individuals at risk for osteoporosis.
The Impact of Vitamin D Supplementation on Fracture Risk
Given the crucial role of vitamin D in bone health, can supplementation help prevent osteoporotic fractures? Several large-scale studies have investigated this question, yielding promising results.
Landmark Studies on Vitamin D Supplementation
The Decalyos study, conducted by Chapuy et al. (1992), demonstrated that vitamin D3 and calcium supplementation significantly reduced hip fracture risk in elderly women. A follow-up study, Decalyos II, confirmed these findings and showed a reversal of secondary hyperparathyroidism in the supplemented group.
Another notable study by Trivedi et al. (2003) found that four-monthly oral vitamin D3 supplementation reduced fracture risk in men and women living in the community. This randomized, double-blind controlled trial provided strong evidence for the benefits of vitamin D supplementation in fracture prevention.
Combined Calcium and Vitamin D Supplementation
Research suggests that combining calcium and vitamin D supplementation may be particularly effective in reducing fracture risk. A study by Dawson-Hughes et al. (1997) showed that calcium and vitamin D supplementation increased bone density in men and women aged 65 years or older.
Similarly, a pragmatic population-based intervention study by Larsen et al. (2004) found that vitamin D and calcium supplementation prevented osteoporotic fractures in elderly community-dwelling residents over a three-year period.
Extraskeletal Effects of Vitamin D
While the role of vitamin D in bone health is well-established, emerging research suggests that this versatile nutrient may have far-reaching effects beyond the skeletal system. What are some of these extraskeletal effects?
Vitamin D and Cancer
Some studies have indicated a potential link between vitamin D and cancer prevention. For instance, research by Tangpricha et al. (2005) found that vitamin D deficiency enhanced the growth of colon cancer xenografts in mice. This suggests that maintaining adequate vitamin D levels may play a role in reducing cancer risk, although more research is needed to confirm these effects in humans.
Vitamin D and Drug Metabolism
Interestingly, vitamin D also interacts with drug metabolism pathways in the body. A study by Zhou et al. (2006) revealed that crosstalk between the vitamin D receptor and the steroid and xenobiotic receptor mediates the expression of CYP24, an enzyme involved in vitamin D metabolism. This interaction can contribute to drug-induced osteomalacia, particularly with certain anticonvulsant medications.
Optimal Vitamin D Levels: Defining the “Normal” Range
Determining the optimal serum vitamin D levels has been a subject of ongoing debate in the scientific community. What constitutes a “normal” vitamin D level, and how does this relate to calcium absorption and overall health?
Serum 25-Hydroxyvitamin D Levels
Serum 25-hydroxyvitamin D is the most commonly used marker of vitamin D status. However, defining a universally accepted “normal” range has proven challenging. A study by Hollis and Wagner (2005) argued for a reevaluation of what constitutes normal serum vitamin D levels, suggesting that higher levels may be beneficial for overall health.
Research by Heaney et al. (2003) demonstrated that calcium absorption varies within the reference range for serum 25-hydroxyvitamin D. This finding suggests that optimal vitamin D levels may be higher than previously thought, particularly for maximizing calcium absorption.
Prevalence of Vitamin D Insufficiency
Even within populations considered “normal,” vitamin D insufficiency may be more common than previously recognized. A study by Chapuy et al. (1997) found a high prevalence of vitamin D insufficiency in an adult normal population, highlighting the need for more widespread vitamin D assessment and supplementation strategies.
Vitamin D and Calcium Homeostasis: Beyond Simple Absorption
While vitamin D is crucial for calcium absorption, its role in calcium homeostasis extends beyond this single function. How does vitamin D interact with other aspects of calcium metabolism and bone health?
Vitamin D Receptor and Bone Phenotype
Research by Amling et al. (1999) provided intriguing insights into the complex relationship between vitamin D and bone health. Their study on vitamin D receptor-ablated mice showed that normal mineral ion homeostasis could rescue the skeletal phenotype associated with vitamin D receptor deficiency. This finding suggests that vitamin D’s effects on bone go beyond its role in calcium absorption and involve direct actions on bone cells.
Vitamin D and Parathyroid Hormone
Vitamin D also plays a crucial role in regulating parathyroid hormone (PTH) levels. Adequate vitamin D status helps suppress excessive PTH secretion, which is important for maintaining bone health. The Decalyos II study by Chapuy et al. (2002) demonstrated that combined calcium and vitamin D supplementation could reverse secondary hyperparathyroidism in elderly women, contributing to a reduction in fracture risk.
Addressing Vitamin D Deficiency in Clinical Settings
Given the high prevalence of vitamin D deficiency and its potential health consequences, how can healthcare providers effectively address this issue in clinical settings?
Screening for Vitamin D Deficiency
A study by Thomas et al. (1998) found a high prevalence of hypovitaminosis D among medical inpatients, highlighting the importance of screening for vitamin D deficiency in hospitalized patients. This finding suggests that routine vitamin D assessment may be beneficial, particularly in high-risk populations.
Tailoring Supplementation Strategies
When addressing vitamin D deficiency, it’s important to consider individual factors that may affect vitamin D status and supplementation needs. These factors include:
- Age
- Skin pigmentation
- Geographic location
- Season
- Body mass index
- Dietary intake
- Sun exposure habits
Healthcare providers should consider these factors when developing vitamin D supplementation strategies for their patients. In some cases, high-dose vitamin D supplementation may be necessary to correct severe deficiency, followed by maintenance doses to sustain optimal levels.
Future Directions in Vitamin D Research
As our understanding of vitamin D’s role in health continues to evolve, what are some promising areas for future research?
Personalized Vitamin D Supplementation
Future studies may focus on developing personalized approaches to vitamin D supplementation based on individual genetic profiles, lifestyle factors, and health status. This could lead to more targeted and effective strategies for optimizing vitamin D levels and overall health outcomes.
Vitamin D and Immune Function
Emerging research suggests that vitamin D may play a role in modulating immune function. Future studies could explore the potential of vitamin D supplementation in preventing or managing autoimmune diseases and improving immune responses to infections.
Long-Term Effects of Vitamin D Supplementation
While many studies have demonstrated the short-term benefits of vitamin D supplementation, more research is needed to understand the long-term effects of maintaining optimal vitamin D levels throughout life. Longitudinal studies could provide valuable insights into the impact of lifelong vitamin D sufficiency on various health outcomes.
In conclusion, the relationship between calcium and vitamin D is complex and multifaceted, extending far beyond simple nutrient absorption. As research in this field continues to advance, it becomes increasingly clear that maintaining optimal vitamin D status is crucial for skeletal health, calcium homeostasis, and potentially a wide range of extraskeletal functions. Healthcare providers and individuals alike should prioritize vitamin D assessment and supplementation as part of a comprehensive approach to health and well-being.
Calcium and Vitamin D: Skeletal and Extraskeletal Health
Papers of particular interest, published recently, have been highlighted as:
• Of importance
•• Of major importance
1••. Holick MF. Vitamin D deficiency. N Engl J Med. 2007;357:266–281. [PubMed] [Google Scholar]N Engl J Med. 2007;357:1980–1981. [Comment in. author reply 1981−1982. [PubMed] [Google Scholar]N Engl J Med. 2007;357:1981. author reply 1981−1982. [Google Scholar]N Engl J Med. 2007;357:1981. author reply 1981−1982. [Google Scholar]N Engl J Med. 2007;357:1981. author reply 1981−1982.]
[Of major importanceThis very comprehensive review of vitamin D deficiency includes 126 references.] [Google Scholar]
2. Tangpricha V, Spina C, Yao M, et al. Vitamin D deficiency enhances the growth of MC-26 colon cancer xenografts in Balb/c mice. J Nutr. 2005;135:2350–2354. [PubMed] [Google Scholar]
3•. Zhou C, Assem M, Tay JC, et al. Steroid and xenobiotic receptor and vitamin D receptor crosstalk mediates CYP24 expression and drug-induced osteomalacia. J Clin Invest. 2006;116:1703–1712. [PMC free article] [PubMed] [Google Scholar]J Clin Invest. 2006;116:2564. Comment in.
[Of importanceThis manuscript was one of the first to describe the mechanism for drug-induced osteomalacia by anticonvulsants.] [PMC free article] [PubMed] [Google Scholar]
4. Walters JR, Balesaria S, Chavele KM, et al. Calcium channel TRPV6 expression in human duodenum: different relationships to the vitamin D system and aging in men and women. J Bone Miner Res. 2006;21:1770–1777. [PubMed] [Google Scholar]
5. Pattanaungkul S, Riggs BL, Yergey AL, et al. Relationship of intestinal calcium absorption to 1,25-dihydroxyvitamin D [1,25(OH)2D] levels in young versus elderly women: evidence for age-related intestinal resistance to 1,25(OH)2D action. J Clin Endocrinol Metab. 2000;85:4023–4027. [PubMed] [Google Scholar]
6. Walters JR, Balesaria S, Khair U, et al. The effects of vitamin D metabolites on expression of genes for calcium transporters in human duodenum. J Steroid Biochem Mol Biol. 2007;103:509–512. [PubMed] [Google Scholar]
7. Amling M, Priemel M, Holzmann T, et al. Rescue of the skeletal phenotype of vitamin D receptor-ablated mice in the setting of normal mineral ion homeostasis: formal histomorphometric and biomechanical analyses. Endocrinology. 1999;140:4982–4987. [PubMed] [Google Scholar]
8. Hollis BW, Wagner CL. Normal serum vitamin D levels. N Engl J Med. 2005;352:515–516. author reply 515−516. [PubMed] [Google Scholar]
9. Chapuy MC, Preziosi P, Maamer M, et al. Prevalence of vitamin D insufficiency in an adult normal population. Osteoporos Int. 1997;7:439–443. [PubMed] [Google Scholar]
10. Heaney RP, Dowell MS, Hale CA, Bendich A. Calcium absorption varies within the reference range for serum 25-hydroxyvitamin D. J Am Coll Nutr. 2003;22:142–146. [PubMed] [Google Scholar]
11. Chapuy MC, Arlot ME, Duboeuf F, et al. Vitamin D3 and calcium to prevent hip fractures in the elderly women. N Engl J Med. 1992;327:1637–1642. [PubMed] [Google Scholar]
12. Chapuy MC, Pamphile R, Paris E, et al. Combined calcium and vitamin D3 supplementation in elderly women: confirmation of reversal of secondary hyperparathyroidism and hip fracture risk: the Decalyos II study. Osteoporos Int. 2002;13:257–264. [PubMed] [Google Scholar]
13. Trivedi DP, Doll R, Khaw KT. Effect of four monthly oral vitamin D3 (cholecalciferol) supplementation on fractures and mortality in men and women living in the community: randomised double blind controlled trial. BMJ. 2003;326:469. [PMC free article] [PubMed] [Google Scholar]
14. Dawson-Hughes B, Harris SS, Krall EA, Dallal GE. Effect of calcium and vitamin D supplementation on bone density in men and women 65 years of age or older. N Engl J Med. 1997;337:670–676. [PubMed] [Google Scholar]ACP J Club. 1998;128:47. Comment in. [Google Scholar]N Engl J Med. 1997;337:701–702. [PubMed] [Google Scholar]
15. Larsen ER, Mosekilde L, Foldspang A. Vitamin D and calcium supplementation prevents osteoporotic fractures in elderly community dwelling residents: a pragmatic population-based 3-year intervention study. J Bone Miner Res. 2004;19:370–378. [PubMed] [Google Scholar]
16. Thomas MK, Lloyd-Jones DM, Thadhani RI, et al. Hypovitaminosis D in medical inpatients. N Engl J Med. 1998;338:777–783. [PubMed] [Google Scholar]N Engl J Med. 1998;339:344–345. Comment in. author reply 345−346. [PubMed] [Google Scholar]N Engl J Med. 1998;339:345–346. [PubMed] [Google Scholar]N Engl J Med. 1998;338:828–829. [PubMed] [Google Scholar]
17. van der Wielen RP, Löwik MR, van den Berg H, et al. Serum vitamin D concentrations among elderly people in Europe. Lancet. 1995;346:207–210. [PubMed] [Google Scholar]
18. Holick MF, Siris ES, Binkley N, et al. Prevalence of Vitamin D inadequacy among postmenopausal North American women receiving osteoporosis therapy. J Clin Endocrinol Metab. 2005;90:3215–3224. [PubMed] [Google Scholar]
19. Tangpricha V, Pearce EN, Chen TC, Holick MF. Vitamin D insufficiency among free-living healthy young adults. Am J Med. 2002;112:659–662. [PMC free article] [PubMed] [Google Scholar]
20. Jackson RD, LaCroix AZ, Gass M, et al.Women’s Health Initiative Investigators Calcium plus vitamin D supplementation and the risk of fractures. N Engl J Med. 2006;354:669–683. [PubMed] [Google Scholar]N Engl J Med. 2006;354:1102. Erratum in. [Google Scholar]ACP J Club. 2006;145:4–5. Comment in. [PubMed] [Google Scholar]Evid Based Nurs. 2006;9:114. [PubMed] [Google Scholar]N Engl J Med. 2006;354:750–752. [PubMed] [Google Scholar]N Engl J Med. 2006;354:2285–2287. author reply 2285−2287. [PubMed] [Google Scholar]N Engl J Med. 2006;354:2285–2287. author reply 2285−2287. [PubMed] [Google Scholar]N Engl J Med. 2006;354:2285–2287. author reply 2285−2287. [PubMed] [Google Scholar]
21. Porthouse J, Cockayne S, King C, et al. Randomised controlled trial of calcium and supplementation with cholecalciferol (vitamin D3) for prevention of fractures in primary care. BMJ. 2005;330:1003. [PMC free article] [PubMed] [Google Scholar]ACP J Club. 2005;143:72–74. Comment in. [PubMed] [Google Scholar]Age Ageing. 2005;34:542–544. [PubMed] [Google Scholar]BMJ. 2005;331:108–109. author reply 109. [Google Scholar]BMJ. 2005;331:108. author reply 109. [Google Scholar]BMJ. 2005;331:108. author reply 109. [Google Scholar]
22. Grant AM, Avenell A, Campbell MK, et al. Oral vitamin D3 and calcium for secondary prevention of low-trauma fractures in elderly people (Randomised Evaluation of Calcium Or vitamin D, RECORD): a randomised placebo-controlled trial. Lancet. 2005;365:1621–1628. [PubMed] [Google Scholar]ACP J Club. 2005;143:72–74. Comment in. [PubMed] [Google Scholar]J Fam Pract. 2005;54:658. [PubMed] [Google Scholar]Lancet. 2005;366:543. author reply 543−544. [Google Scholar]Lancet. 2005;366:543. author reply 543−544. [Google Scholar]Lancet. 2005;366:544. [Google Scholar]Lancet. 2005;365:1599–1600. [PubMed] [Google Scholar]
23. Lips P, Graafmans WC, Ooms ME, et al. Vitamin D supplementation and fracture incidence in elderly persons. A randomized, placebo-controlled clinical trial. Ann Intern Med. 1996;124:400–406. [PubMed] [Google Scholar]ACP J Club. 1996;125:16. Comment in. [Google Scholar]
24. Meyer HE, Smedshaug GB, Kvaavik E, et al. Can vitamin D supplementation reduce the risk of fracture in the elderly? A randomized controlled trial. J Bone Miner Res. 2002;17:709–715. [PubMed] [Google Scholar]
25•. Boonen S, Lips P, Bouillon R, et al. 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;92:1415–1423.
[Of importanceThis meta-analysis demonstrates that vitamin D and calcium together are most effective in preventing hip fractures.] [PubMed] [Google Scholar]
26. Bischoff-Ferrari HA, Dawson-Hughes B. Where do we stand on vitamin D? Bone. 2007;41(1 Suppl 1):S13–19. [PubMed] [Google Scholar]
27. Holick MF. High prevalence of vitamin D inadequacy and implications for health. Mayo Clin Proc. 2006;81:353–373. [PubMed] [Google Scholar]Mayo Clin Proc. 2006;81:297–299. Comment in. [PubMed] [Google Scholar]
28. Bischoff-Ferrari HA, Dietrich T, Orav EJ, et al. Higher 25-hydroxyvitamin D concentrations are associated with better lower-extremity function in both active and inactive persons aged > or = 60 y. Am J Clin Nutr. 2004;80:752–758. [PubMed] [Google Scholar]
29. Bischoff-Ferrari HA, Dawson-Hughes B, Willett WC, et al. Effect of vitamin D on falls: a meta-analysis. JAMA. 2004;291:1999–2006. [PubMed] [Google Scholar]
30. Cantorna MT, Zhu Y, Froicu M, Wittke A. Vitamin D status, 1,25-dihydroxyvitamin D3, and the immune system. Am J Clin Nutr. 2004;80(6 Suppl):1717S–1720S. [PubMed] [Google Scholar]
31. Vaisberg MW, Kaneno R, Franco MF, Mendes NF. Influence of cholecalciferol (vitamin D3) on the course of experimental systemic lupus erythematosus in F1 (NZBxW) mice. J Clin Lab Anal. 2000;14:91–96. [PMC free article] [PubMed] [Google Scholar]
32. Merlino LA, Curtis J, Mikuls TR, et al.Iowa Women’s Health Study Vitamin D intake is inversely associated with rheumatoid arthritis: results from the Iowa Women’s Health Study. Arthritis Rheum. 2004;50:72–77. [PubMed] [Google Scholar]Arthritis Rheum. 2006;54:3719–3720. Comment in. [PubMed] [Google Scholar]
33•. Costenbader KH, Feskanich D, Benito-Garcia E, et al. Vitamin D intake and risks of systemic lupus erythematosus and rheumatoid arthritis in women. Ann Rheum Dis. 2007 [Epub ahead of print].
[Of importanceA prospective cohort study of the Nurses’ Health Study and Nurses’ Health Study II cohorts. After 22 years of follow-up, of 186,389 women, investigators found 190 new cases of confirmed SLE and 722 new cases of RA. No association was found between vitamin D intake (based on food frequency questionnaire) and incidence of SLE or RA.] [PMC free article] [PubMed] [Google Scholar]
34. Munger KL, Levin LI, Hollis BW, et al. Serum 25-hydroxyvitamin D levels and risk of multiple sclerosis. JAMA. 2006;296:2832–2838. [PubMed] [Google Scholar]
35. Liu PT, Stenger S, Li H, et al. Toll-like receptor triggering of a vitamin D-mediated human antimicrobial response. Science. 2006;311:1770–1773. [PubMed] [Google Scholar]
36•. Mathieu C, Gysemans C, Giulietti A, Bouillon R. Vitamin D and diabetes. Diabetologia. 2005;48:1247–1257.
[Of importanceThis is a very well-written review for the evidence of vitamin D in the prevention of type 1 and type 2 diabetes.] [PubMed] [Google Scholar]
37. Scragg R, Sowers M, Bell C. Serum 25-hydroxyvitamin D, ethnicity, and blood pressure in the Third National Health and Nutrition Examination Survey. Am J Hypertens. 2007;20:713–719. [PubMed] [Google Scholar]
38. Ford ES, Ajani UA, McGuire LC, Liu S. Concentrations of serum vitamin D and the metabolic syndrome among U.S. adults. Diabetes Care. 2005;28:1228–1230. [PubMed] [Google Scholar]
39. Judd SE, Nanes MS, Ziegler TR, et al. Optimal vitamin D status attenuates the age-associated increase in systolic blood pressure in white Americans: results from the third National Health and Nutrition Examination Survey. Am J Clin Nutr. 2008;87:136–141. [PubMed] [Google Scholar]
40. Pfeifer M, Begerow B, Minne HW, et al. Effects of a short-term vitamin D(3) and calcium supplementation on blood pressure and parathyroid hormone levels in elderly women. J Clin Endocrinol Metab. 2001;86:1633–1637. [PubMed] [Google Scholar]
41. Hsia J, Heiss G, Ren H, et al.Women’s Health Initiative Investigators Calcium/vitamin D supplementation and cardiovascular events. Circulation. 2007;115:846–854. [PubMed] [Google Scholar]Circulation. 2007;115:e466. Erratum in. [Google Scholar]Circulation. 2007;115:827–828. Comment in. [PubMed] [Google Scholar]Circulation. 2007;116:e85. author reply e87. [PubMed] [Google Scholar]Circulation. 2007;116:e86. author reply e87. [PubMed] [Google Scholar]
42••. Autier P, Gandini S. Vitamin D supplementation and total mortality: a meta-analysis of randomized controlled trials. Arch Intern Med. 2007;167:1730–1737.
[Of major importanceThis very intriguing manuscript reviewed all randomized placebo-controlled trials with vitamin D in which death was collected as an end point. The results show a survival advantage when taking usual over-the-counter doses of vitamin D (∼500 IU daily).] [PubMed] [Google Scholar]
43•. Lappe JM, Travers-Gustafson D, Davies KM, et al. Vitamin D and calcium supplementation reduces cancer risk: results of a randomized trial. Am J Clin Nutr. 2007;85:1586–1591. [PubMed] [Google Scholar]Am J Clin Nutr. 2007;86:1804–1805. [Comment in. author reply 1805−1806. [PubMed] [Google Scholar]Am J Clin Nutr. 2007;86:1549. author reply 1549−1550.]
[Of importanceA double-blind, randomized controlled trial of Nebraska women with primary outcome of fractures and principal secondary outcome of cancer incidence. Subjects (n = 1179) were randomly assigned to calcium (1400−1500 mg) plus vitamin D (1100 IU), calcium alone, or placebo, with a 4-year follow-up. Treatment with vitamin D and levels of 25(OH)D were significantly associated with decreased cancer incidence, with a RR of 0.232 for cancers diagnosed 1 year after study initiation in the vitamin D and calcium group. ] [PubMed] [Google Scholar]
44. Huybers S, Naber TH, Bindels RJ, Hoenderop JG. Predniso-lone-induced Ca2+ malabsorption is caused by diminished expression of the epithelial Ca2+ channel TRPV6. Am J Physiol Gastrointest Liver Physiol. 2007;292:G92–G97. [PubMed] [Google Scholar]
45. Recker RR. Calcium absorption and achlorhydria. N Engl J Med. 1985;313:70–73. [PubMed] [Google Scholar]
46. Sakhaee K, Bhuket T, Adams-Huet B, Rao DS. Meta-analysis of calcium bioavailability: a comparison of calcium citrate with calcium carbonate. Am J Ther. 1999;6:313–321. [PubMed] [Google Scholar]Am J Ther. 2001;8:73–74. Comment in. [PubMed] [Google Scholar]Am J Ther. 2001;8:74–77. [PubMed] [Google Scholar]
47. Heaney RP, Dowell MS, Bierman J, et al. Absorbability and cost effectiveness in calcium supplementation. J Am Coll Nutr. 2001;20:239–246. [PubMed] [Google Scholar]
48. Recker RR, Bammi A, Barger-Lux MJ, Heaney RP. Calcium absorbability from milk products, an imitation milk, and calcium carbonate. Am J Clin Nutr. 1988;47:93–95. [PubMed] [Google Scholar]
49. Armas LA, Hollis BW, Heaney RP. Vitamin D2 is much less effective than vitamin D3 in humans. J Clin Endocrinol Metab. 2004;89:5387–5391. [PubMed] [Google Scholar]
50. Kamen DL, Cooper GS, Bouali H, et al. Vitamin D deficiency in systemic lupus erythematosus. Autoimmun Rev. 2006;5:114–117. [PubMed] [Google Scholar]
51. Harvey JA, Zobitz MM, Pak CY. Dose dependency of calcium absorption: a comparison of calcium carbonate and calcium citrate. J Bone Miner Res. 1988;3:253–258. [PubMed] [Google Scholar]
Calcium/Vitamin D Requirements, Recommended Foods & Supplements
Calcium and vitamin D are essential to building strong, dense bones both when you’re young and as you age. The information included here will help you learn all about calcium and vitamin D – the two most important nutrients for bone health.
It is equally important to continue getting enough calcium and vitamin D to prevent further bone loss if you are prescribed a medication to prevent bone loss or fractures.
What is Calcium and What Does it Do?
A calcium-rich diet (including dairy, nuts, leafy greens and fish) helps to build and protect your bones.
Calcium is a mineral that is necessary for life. In addition to building bones and keeping them healthy, calcium enables our blood to clot, our muscles to contract, and our heart to beat. About 99% of the calcium in our bodies is in our bones and teeth.
Every day, we lose calcium through our skin, nails, hair, sweat, urine and feces. Our bodies cannot produce its own calcium. That’s why it’s important to get enough calcium from the food we eat. When we don’t get the calcium our body needs, it is taken from our bones. This imbalance causes bones get weak and easier to break.
Too many Americans fall short of getting the amount of calcium they need every day and that can lead to bone loss, low bone density and even broken bones.
How Much Calcium Do You Need?
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The amount of calcium you need every day depends on your age and sex.
Women | |
---|---|
Age 50 & younger | 1,000 mg* daily |
Age 51 & older | 1,200 mg* daily |
Men | |
---|---|
Age 70 & younger | 1,000 mg* daily |
Age 71 & older | 1,200 mg* daily |
*This includes the total amount of calcium you get from food and supplements.
How Much Calcium Do You Eat?
Use the International Osteoporosis Foundation’s Calcium Calculator to find out.
Sources of Calcium
Calcium-Rich Food Sources
Food is the best source of calcium. Dairy products, such as milk, yogurt, and cheese are high in calcium. Certain green vegetables and other foods contain calcium in smaller amounts. Some juices, breakfast foods, soymilk, cereals, snacks, breads and bottled water have added calcium in fortified foods. If you consume soymilk, other nut based milks ( i.e.: almond or oat milk) or another liquid that is fortified with calcium, be sure to shake the container well as calcium can settle to the bottom.
A simple way to add calcium to many foods is to add a single tablespoon of nonfat powdered milk, which contains about 50 mg of calcium. It is easy to add a few tablespoons to almost any recipe.
Reading Food Labels – How Much Calcium Am I Getting?
To determine how much calcium is in a particular food, check the nutrition facts panel for the daily value (DV). Food labels list calcium as a percentage of the DV. This amount is based on 1,000 mg of calcium per day. For example:
- 30% DV of calcium equals 300 mg of calcium.
- 20% DV of calcium equals 200 mg of calcium.
- 15% DV of calcium equals 150 mg of calcium.
Calcium Supplements
The amount of calcium you need from a supplement depends on how much you get from food. Try to get the daily amount recommended from food and only supplement as needed to achieve the recommend daily allowance. In general, you shouldn’t take excess supplements that you don’t need. If you get enough calcium from foods, you may not need to take a supplement. There is no added benefit to taking more calcium than you need. Doing so may even carry some risks such as constipation, kidney stones and perhaps excess heart calcification.
Calcium supplements are available without a prescription in a wide range of preparations (including chewable tablets, gummy preparations, powders and liquid) and in varying amounts and sizes. The best supplement is the one that meets your needs for tolerability, convenience, cost, and availability. When choosing a supplement, keep the following in mind:
- Choose brand-name supplements with proven reliability. Look for labels that state “purified” or have the USP (United States Pharmacopeia) symbol. The “USP Verified Mark” on the supplement label means that the USP has tested and found the calcium supplement to meet its standards for purity and quality.
- Read the product label carefully to determine the amount of elemental calcium, which is the actual amount of calcium in the supplement, as well as how many doses or pills you have to take. When reading the label, pay close attention to the “amount per serving” and “serving size.”
- Calcium is absorbed best when taken in amounts of 500 – 600 mg or less. This is the case for both foods and supplements. Try to get your calcium-rich foods and/or supplements in small amounts throughout the day, preferably with a meal. While it’s not recommended, taking your calcium all at once is better than not taking it at all.
- Take (most) calcium supplements with food. Eating food produces stomach acid that helps your body absorb most calcium supplements. The one exception to the rule is calcium citrate, which can absorb well when taken with or without food.
- When starting a new calcium supplement, start with a smaller amount to better tolerate it. When switching supplements, try starting with 200-300 mg every day for a week, and drink an extra 6-8 ounces of water with it. Then gradually add more calcium each week.
- Side effects from calcium supplements, such as gas or constipation may occur or worsen. If increasing fluids in your diet and obtaining enough fiber does not solve the problem, try another type or brand of calcium. It may require trial and error to find the right supplement for you, but fortunately there are many choices.
- Talk with your healthcare provider or pharmacist about possible interactions between prescription or over-the-counter medications and calcium supplements.
What is Vitamin D and What Does it Do?
Vitamin D is a fat soluble vitamin and plays an important role in protecting your bones, both by helping your body absorb calcium and by supporting muscles needed to avoid falls. Children need vitamin D to build strong bones, and adults need it to keep their bones strong and healthy.
How Much Vitamin D Do You Need?
Women and Men | |
---|---|
Under age 50 | 400-800 international units (IU) daily** |
Age 50 and older | 800-1,000 IU daily** |
**According to the National Academy of Medicine and National Institutes of Health the safe upper limit of vitamin D is 4,000 IU per day for most adults. These recommendations are for the general healthy adult population.
Sources of Vitamin D
There are three ways to get vitamin D:
- Sunlight
- Food
- Supplements
Sunlight
Your skin makes vitamin D in reaction to sunlight and stores it in fat for later use. How much vitamin D your skin can produce depends on time of day, season, latitude, skin pigmentation, age, and other factors.
There are many reasons people do not have enough vitamin D. As we age, our skin loses its ability to generate vitamin D. People who live in cities or in institutional settings like nursing homes spend too little time outdoors. Even people who spend time outdoors often use sunscreen to prevent skin cancer. Sunscreen with an SPF as low as 8 reduces vitamin D production by 95 percent.
Vitamin D in Food
Vitamin D is found in very few foods. Sources include fatty fish like wild-caught mackerel, salmon, and tuna. Vitamin D is added to milk and other dairy products, orange juice, soymilk, and fortified cereals.
Check the food label to see if vitamin D has been added to a particular product. One eight-ounce serving of milk usually has 25% of the daily value (DV) of vitamin D. The DV is based on a total daily intake of 400 IU of vitamin D. So, a serving of milk with 25% of the DV of vitamin D contains 100 IU.
It is often difficult to get all the vitamin D you need from sunlight and food alone. Some people with underlying conditions may need to take vitamin D supplements to support bone health.
Vitamin D Supplements
Healthy adults with no vitamin D deficiency should be able to get adequate amounts of vitamin D from sunlight and by consuming a well-balanced diet. People with osteoporosis and low bone mass should discuss their vitamin D levels with their healthcare provider to ensure they are getting an optimal amount.
Before adding a vitamin D supplement, check to see if any of the other supplements, multivitamins, or medications you take contain vitamin D. Many calcium supplements also contain some vitamin D.
There are two types of vitamin D supplements. They are vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). Both types are good for bone health.
Vitamin D supplements can be taken with or without food and the full amount can be taken at one time. While your body needs vitamin D to absorb calcium, you do not need to take vitamin D at the same time as a calcium supplement. If you need help choosing a vitamin D supplement, ask your healthcare provider to recommend one.
Vitamin D Deficiency: Are You at Risk?
Vitamin D deficiency occurs when you are not getting the recommended level of vitamin D over time. Certain people are at higher risk for vitamin D deficiency, including:
- People who spend little time in the sun or those who regularly cover up when outdoors;
- People living in nursing homes or other institutions or who are homebound;
- People with certain medical conditions such as Celiac disease and inflammatory bowel disease;
- People taking medicines that affect vitamin D levels such as certain anti-seizure medicines;
- People with very dark skin;
- Obese or very overweight people; and
- Older adults with certain risk factors.
Talk to your healthcare provider if you have any of these risk factors. If you have osteoporosis, low bone mass or another medical condition that can lead to bone loss and also have a vitamin D deficiency, your healthcare provider may recommend vitamin D supplement to bring you up to a healthy 25-hydroxy vitamin D level which is generally agreed upon by medical societies to be between 30-60 ng/ml.
A Guide to Calcium-Rich Foods
We all know that milk is a great source of calcium, but you may be surprised by all the different foods you can work into your diet to reach your daily recommended amount of calcium. Use the guide below to get ideas of additional calcium-rich foods to add to your weekly shopping list.
Produce | Serving Size | Estimated Calcium* |
Collard greens, frozen | 8 oz | 360 mg |
Broccoli rabe | 8 oz | 200 mg |
Kale, frozen | 8 oz | 180 mg |
Soy Beans, green, boiled | 8 oz | 175 mg |
Bok Choy, cooked, boiled | 8 oz | 160 mg |
Figs, dried | 2 figs | 65 mg |
Broccoli, fresh, cooked | 8 oz | 60 mg |
Oranges | 1 whole | 55 mg |
Seafood | Serving Size | Estimated Calcium* |
Sardines, canned with bones | 3 oz | 325 mg |
Salmon, canned with bones | 3 oz | 180 mg |
Shrimp, canned | 3 oz | 125 mg |
Dairy | Serving Size | Estimated Calcium* |
Ricotta, part-skim | 4 oz | 335 mg |
Yogurt, plain, low-fat | 6 oz | 310 mg |
Milk, skim, low-fat, whole | 8 oz | 300 mg |
Yogurt with fruit, low-fat | 6 oz | 260 mg |
Mozzarella, part-skim | 1 oz | 210 mg |
Cheddar | 1 oz | 205 mg |
Yogurt, Greek | 6 oz | 200 mg |
American Cheese | 1 oz | 195 mg |
Feta Cheese | 4 oz | 140 mg |
Cottage Cheese, 2% | 4 oz | 105 mg |
Frozen yogurt, vanilla | 8 oz | 105 mg |
Ice Cream, vanilla | 8 oz | 85 mg |
Parmesan | 1 tbsp | 55 mg |
Fortified Food | Serving Size | Estimated Calcium* |
Almond milk, rice milk, soy milk, oat milk fortified | 8 oz | 300 mg |
Orange juice and other fruit juices, fortified | 8 oz | 300 mg |
Tofu, prepared with calcium | 4 oz | 205 mg |
Waffle, frozen, fortified | 2 pieces | 200 mg |
Oatmeal, fortified | 1 packet | 140 mg |
English muffin, fortified | 1 muffin | 100 mg |
Cereal, fortified 35 | 8 oz | 100-1,000 mg |
Other | Serving Size | Estimated Calcium* |
Mac & cheese, frozen | 1 package | 325 mg |
Pizza, cheese, frozen | 1 serving | 115 mg |
Pudding, chocolate, prepared with 2% milk | 4 oz | 160 mg |
Beans, baked, canned | 4 oz | 160 mg |
*The calcium content listed for most foods is estimated and can vary due to multiple factors. Check the food label to determine how much calcium is in a particular product.
Resources
–Show More +
- Calcium and Vitamin D Supplement Safety Fact Sheet
- Just the Facts: Latest Evidence-Based Research on Calcium from the National Institutes of Health (NIH) Office of Dietary Supplements (ODS)
Last Reviewed 5/23/2023
How vitamin D and calcium work and why it is better to use them in pairs
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Do not self-medicate! In our articles, we collect the latest scientific data and the opinions of authoritative health experts. But remember: only a doctor can diagnose and prescribe treatment.
Advertisements urge us to buy and drink vitamin D and calcium supplements and assure us that this will solve many health problems. Is this true, or is the general obsession with these elements just the result of successful pharmaceutical marketing? Larisa Gennadievna Bavykina, an endocrinologist and nutritionist, a geneticist at the Atlas Medical Center , answers a controversial question.
What is Vitamin D? Pediatricians at the beginning of the 20th century began to recommend spending at least 15 minutes a day in the sun and consuming cod liver oil regularly.
At the beginning of the 21st century, numerous studies were carried out that contributed to the popularization of vitamin D. Scientists have found that it has an unusual structure for vitamins and affects many processes in the body. In addition, vitamin D is similar to a hormone in that it has receptors in various organs and tissues. For example, in osteoblasts (young bone cells). And vitamin D receptors in the gut help absorb calcium.
The basis of vitamin D is cholesterol, so this vitamin can penetrate into all cells of the body.
Production methods
- Direct sunlight. The arms should be bare to the middle of the shoulder, the face and neck should be open. If these conditions are met for 5-15 minutes 2-3 times a week in the morning or evening, you will provide the body with vitamin D in the summer. But the abuse of sunlight – sunburn – is already harmful to health and increases the risk of skin cancer.
- Vitamin D fortified milk or fish oil. Milk is irradiated on a conveyor belt with an ultraviolet lamp, and a precursor of vitamin D is formed from cholesterol. Fish oil is obtained from cod liver, which is naturally rich in this vitamin.
- Preparations. Aqueous and oil solutions of vitamin D. This is a priority method of obtaining this vitamin in our time in the autumn, winter and spring periods.
Vitamin deficiency
You should not prescribe this vitamin yourself, especially since the symptoms of its deficiency are nonspecific and may indicate other pathologies.
Ask an endocrinologist or general practitioner to prescribe the drug in late summer – early autumn, if possible, take an analysis for vitamin D levels. The doctor will determine what dose of this vitamin to prescribe – preventive or saturating.
In addition, according to recent studies, the absorption of vitamin D is influenced by certain genes, more precisely, the genes “supervise” the work of various enzymes involved in the absorption of vitamin D. Thus, the DHCR7 gene regulates the work of the enzyme 7-dehydrocholesterol reductase, which is necessary for the synthesis vitamin D precursor. The CYP2R1 gene is responsible for liver enzymes involved in vitamin D metabolism. The GC gene regulates the activity of a protein that binds and transports this vitamin and its metabolites in the liver. Because of this complex system, it turns out that people under the same living conditions have different levels of vitamin D, which depends on genetic characteristics.
Vitamin D has a positive effect on the immune system, helps maintain bone density and prevents osteoporosis.
Benefits of calcium
Calcium is involved in a variety of body processes:
- important for bone metabolism;
- supports bone strength;
- helps melatonin formation;
- provides muscle contractions and conduction of nerve impulses.
To prevent calcium deficiency, fermented milk products should be consumed, and products marked “fortified with calcium” are also acceptable. With a lack of calcium, the body “takes” it from the bones, and they become “leaky”, the risk of fractures increases and osteoporosis develops.
Where to look for calcium
Calcium and vitamin D are interconnected: milk and dairy products contain bioavailable calcium, but it is well absorbed only when there is enough vitamin D in the body. Only in commonwealth of these two elements reduce the risk of developing osteoporosis.
Calcium is found not only in dairy products, but also in nuts, nut milk, green vegetables (spinach, broccoli, etc.). The problem is that 100 g of hard cheese contains the same amount of calcium as 1 kg of broccoli and 15 kg of spinach. Therefore, it is easier to get the necessary element from fermented milk products or medicines prescribed by a doctor.
What vitamin ensures the absorption of calcium in the body
THERE ARE CONTRAINDICATIONS. SPECIALIST CONSULTATION IS REQUIREDVitamin DVitamins of group BCalciumMagnesiumZinc
Contents of the article
- What effect does calcium have on the human body?
- What vitamin ensures the absorption of calcium in the body?
- What foods are the best sources of calcium absorption
- What foods flush calcium out of the body
- Sources
Calcium (Ca) is one of the few elements that is necessary for almost every cell. Without it, the full formation of tissues and the normal course of biochemical processes are impossible. The body cannot synthesize Ca on its own. Food and special additives provide its replenishment.
But in order to replenish the reserves, it is not enough to receive the necessary doses of the microelement. You also need to create conditions for its assimilation. A number of useful substances contribute to this process. What vitamin ensures the absorption of calcium and what is the role of this nutrient?
What effect does calcium have on the human body?
The distribution of Ca in the body is uneven – 99% of the element is contained in the teeth and bones, and only 1% is distributed to other organs. The substance comes in from the outside, and its excretion is provided by the kidneys and intestines.
Functions performed by Ca:
- Balances the processes of excitation and inhibition in the cerebral cortex
- Necessary for bone formation and mineralization of teeth
- Affects the heart rhythm and blood clotting
- Participates in the formation of many hormones and enzymes;
- Helps to strengthen the immune system
The substance provides bone strength. At the same time, bone tissue acts as a kind of depot for its storage. With a deficiency of an element, the body begins to use these reserves. Prolonged removal of the mineral from the bones leads to osteoporosis, deterioration of the central nervous system (CNS) and heart, tooth decay, and the development of allergic reactions.
Ca deficiency in children is manifested by metabolic disorders, pathological formation of the musculoskeletal system and teeth, and poor sleep.
The need for the mineral depends on age. In addition, gender, lifestyle, and the presence of diseases matter. Large doses of the nutrient (up to 1500 mg) are necessary for women during pregnancy, breastfeeding, postmenopausal women.
However, an excess of the substance can also lead to health problems. The use of more than 2.5 mg of calcium per day causes a deterioration in appetite, constipation, increased blood pressure (BP), convulsions, and increases the risk of calculus formation. Therefore, the mineral should enter the body only in the required quantities. And for its full assimilation, it is necessary to take preparations additionally enriched with other vitamins and microelements.
What vitamin ensures the absorption of calcium in the body?
Ca absorption is a complex process, for which vitamin D is primarily important. It improves the absorption of the mineral in the small intestine and helps strengthen bones. With a lack of vitamin, calcium can be poorly absorbed even when taken in the right quantities.
In addition, vitamins act as a support group:
- C – accelerates the maturation of collagen, which acts as a natural support for bone tissue, skin, blood vessels. Protects blood vessels and the heart, prevents the development of allergies.
- B6 – improves the absorption of magnesium, necessary for the full functioning of the central nervous system.
- K1 – prevents osteoporosis. Together with vitamin D, it is involved in the synthesis of osteocalcin, which helps to retain calcium. Reduces the risk of fractures.
Minerals are also needed for better absorption of Ca: magnesium (Mg), phosphorus (P), zinc (Zn), iodine (I).
Fully provide the body’s need for calcium and its maximum assimilation of such combined preparations as Calcium D-3 Nikomid-Forte, Calcemin, Osteogenon. But you can take them only as prescribed by a doctor. In the absence of the opportunity to consult with a specialist, stocks can be replenished with food.
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From which foods calcium is best absorbed
Many foods are rich in calcium. To replenish the body with a mineral, you need to include in the diet:
- Sesame seeds – most Ca contains seed coats, so you need to use unpeeled seeds. Peeled sesame seeds practically do not bring benefits.
- Milk and dairy products – the element is best absorbed from pasteurized milk. UHT and sterilized dairy products contain much fewer substances that help good absorption of Ca.
- Greens, vegetables, nuts, berries and fruits – compared to milk, they have less calcium. The element is best absorbed from raw vegetables and fruits.
Combining these products, you can provide the body with the necessary amount of the substance. However, Ca is easily washed out. Therefore, it is necessary not only to saturate the body with a mineral, but also to prevent its leaching.
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contribute to its leaching from the bone tissue. These include:
- Palm oil – prevents the absorption of calcium and many useful substances.
- Coffee – flushes Ca and other minerals from the body. No more than 4 cups of coffee with a capacity of 30 ml are allowed per day.
- Sweets – disturb the intestinal microflora, in which all useful substances are absorbed.
- Sweet water – also disrupts the functioning of the intestines and interferes with the absorption of the trace element. Some drinks contain caffeine, which washes away beneficial elements.
In addition, products with a high salt content, animal fats, and all alcoholic beverages interfere with the absorption of the mineral and contribute to its leaching.