Calcium Intake and Blood Pressure: An Update

Cappuccio FP Elliott P Allender PS Pryer J Follman DA Cutler JA. Epidemiologic association between dietary calcium intake and blood pressure: a meta-analysis of published data. Am J Epidemiol 1995; 142: 935–945.

Hamet P. The evaluation of the scientific evidence for a relationship between calcium and hypertension. J Nutr 1995; 125 (suppl):311–400.

Bucher HC Cook RJ Guyatt GH Lang JD Cook DJ Hatala R . Effects of dietary calcium supplementation on blood pressure: a meta-analysis of randomized controlled trials. JAMA 1996; 275: 1016–1022.

In total 33 randomized trials of calcium supplementation and blood pressure, published between May 1994 and 1996, were selected for the meta-analysis according to six quality criteria. The pooled findings showed that a significant 1.3 mmHg reduction in systolic blood pressure was caused by supplementation with 1000–2000 mg calcium per day. Reductions in blood pressure for short-term (1–3 months) and long-term (> 6 months) intervention were of the same magnitude. The combined trial data show that only minor effects on the population's level of blood pressure can be achieved by means of calcium supplements.

Bucher HC Guyatt GH Cook RJ Hatala R Cook DJ Lang JD . Effect of calcium supplementation on pregnancy-induced hypertension and preeclampsia: a meta-analysis of randomized controlled trials. JAMA 1996; 275: 1113–1117.

Allender PS Cutler JA Follmann D Cappuccio FP Pryer J Elliott P. Dietary calcium and blood pressure: a meta-analysis of randomized clinical trials. Ann Intern Med 1996; 124: 825–831.

Pryer J Cappuccio FP Elliott P. Dietary calcium and blood pressure: a review of the observational studies. J Hum Hypertens 1995; 9: 597–604.

Birkett NJ. Comments on a meta-analysis of the relation between dietary calcium intake and blood pressure. Am J Epidemiol 1998; 148: 223–228.

The meta-analysis included observational data from 23 populations, published between January 1983 and November 1993. The pooled regression coefficients indicated that there is a 0.4 mmHg reduction in systolic and diastolic blood pressure per 100 mg increase in intake of calcium which is around three times larger than the average reduction in blood pressure found in trials of calcium supplementation.

Stoto MA. Invited commentary on meta-analysis of epidemiologic data: the case of calcium intake and blood pressure. Am J Epidemiol 1998; 148: 229–231.

Geleijnse JM Witteman JC den Breeijen JH Hofman A de Jong PT Pols HA . Dietary electrolyte intake and blood pressure in older subjects: the Rotterdam Study. J Hypertens 1996; 14: 737–741.

Van Leer EM Seidell JC Kromhout D. Dietary calcium, potassium, magnesium and blood pressure in the Netherlands. Int J Epidemiol 1995; 24: 1117–1123.

Tian HG Nan Y Shao RC Dong QN Hu G Petinen P . Associations between blood pressure and dietary intake and urinary excretion of electrolytes in a Chinese population. J Hypertens 1995; 13: 49–56.

Stamler J Elliott P Kesteloot H Nichols R Claeys G Dyer AR . Inverse relation of dietary protein markers with blood pressure: findings for 10,020 men and women in the INTERSALT Study. Circulation 1996; 94: 1629–1634.

Witteman JC Willett WC Stampfer MJ Colditz GA Sacks FM Speizer FE . A prospective study of nutritional factors and hypertension among US women. Circulation 1989; 80: 1320–1327.

Ascherio A Hennekens C Willett WC Sacks F Rosner B Manson J . Prospective study of nutritional factors, blood pressure, and hypertension among US women. Hypertension 1996; 27: 1065–1072.

Dwyer JH Li L Dwyer KM Curtin LR Feinleib M. Dietary calcium, alcohol, and incidence of treated hypertension in the NHANES I epidemiologic follow-up study. Am J Epidemiol 1996; 144: 828–838.

A 1 g increase in daily intake of calcium was associated with a significant reduction in risk of hypertension among 6634 NHANES I participants during 10 years of follow-up (odds ratio 0.84), except for daily drinkers, among whom an increase in risk of hypertension was observed (odds ratio 1.33). There was no interaction with sex and race.

Ascherio A Rimm EB Giovannucci EL Colditz GA Rosner B Willett WC . A prospective study of nutritional factors and hypertension among US men. Circulation 1992; 86: 1475–1484.

Singh RB Rastogi SS Singh NK Ghosh S Gupta S Niaz MA. Can guava fruit intake decrease blood pressure and blood lipids? J Hum Hypertens 1993; 7: 33–38.

Allender PS Cutler JA Follmann D. Dietary calcium and blood pressure [letter]. Ann Intern Med 1997; 126: 492–493.

Whelton PK Kumanyika SK Cook NR Cutler JA Borhani NO Hennekens CH . Efficacy of nonpharmacologic interventions in adults with high-normal blood pressure: results from phase 1 of the Trials of Hypertension Prevention. Am J Clin Nutr 1997; 65 (suppl):652–660.

Calcium supplementation for 6 or 18 months did not lower blood pressure in 2181 middle-aged men and women with high normal diastolic blood pressures. Weight loss and reduction in intake of sodium, however, appeared effective at reducing the risk of hypertension.

Appel U Moore TJ Obarzanek E Vollmer WM Svetkey LP Sacks FM . A clinical trial of the effects of dietary patterns on blood pressure. N Engl J Med 1997; 336: 1117–1124.

The effect of dietary patterns on blood pressure was studied in the randomized DASH trial, involving 459 adults. A diet rich in fruit, vegetables, and low-fat dairy products significantly lowered blood pressure. Low-fat dairy products accounted for a 2–3 mmHg fall in blood pressure. Decreases in blood pressure in hypertensions were three times larger than those in normotensives. Results of this study suggest that calcium as part of a dietary matrix exerts a stronger effect on blood pressure than do calcium supplements.

Yamamoto ME Applegate WB Klag MJ Borhani NO Cohen JD Kirchner KA . Lack of blood pressure effect with calcium and magnesium supplementation in adults with high-normal blood pressure. Results from Phase I of the Trials of Hypertension Prevention (TOHP). Ann Epidemiol 1995; 5: 96–107.

In the randomized Trials of Hypertension Prevention, a very high compliance with daily calcium and magnesium supplementation was achieved by 698 middle-aged adults with high normal diastolic blood pressures. Neither calcium nor magnesium supplementation caused significant changes in blood pressure after 3 and 6 months. Subgroup analyses, however, raised the possibility that calcium supplements exert a beneficial effect on white women with low habitual intakes of calcium.

NIH Consensus Development Panel on Optimal Calcium Intake. Optimal calcium intake. JAMA 1994; 272: 1942–1948.

Hatton DC McCarron DA. Dietary calcium and blood pressure in experimental models of hypertension [review]. Hypertension 1994; 23: 513–530.

Grobbee DE Waal-Manning HJ. The role of calcium supplementation in the treatment of hypertension. Current evidence. Drugs 1990; 39: 7–18.

Sacks FM Willett WC Smith A Brown LE Rosner B Moore TJ. Effect on blood pressure of potassium, calcium, and magnesium in women with low habitual intake. Hypertension 1998; 31: 131–138.

Dwyer JH Dwyer KM Scribner RA Sun P Li L Nicholson LM . Dietary calcium, calcium supplementation, and blood pressure in African American adolescents. Am J Clin Nutr 1998; 68: 648–655.

Gillman MW Hood MY Moore LL Nguyen US Singer MR Andon MB. Effect of calcium supplementation on blood pressure in children. J Pediatr 1995; 127: 186–192.

Simons-Morton DG Obarzanek E. Diet and blood pressure in children and adolescents. Pediatr Nephrol 1997; 11: 244–249.

Gillman MW Oliveria SA Moore LL Ellison RC. Inverse association of dietary calcium with systolic blood pressure in young children. JAMA 1992; 267: 2340–2343.

Liebman M Chopin LF Carter E Clark AJ Disney GW Hegsted M . Factors related to blood pressure in a biracial adolescent female population. Hypertension 1986; 8: 843–850.

Simons-Morton DG Hunsberger SA Van Horn L Barton BA Robson AM McMahon RP . Nutrient intake and blood pressure in the Dietary Intervention Study in Children. Hypertension 1997; 29: 930–936.

Grobbee DE Hofman A. Effect of calcium supplementation on diastolic blood pressure in young people with mild hypertension. Lancet 1986; ii: 703–707.

Calcium supplementation of young adults with mildly elevated blood pressure for 12 weeks caused a 2–3 mmHg decrease in diastolic blood pressure. Reductions in blood pressure were more pronounced for subjects in subgroups with low serum levels of calcium, high plasma levels of parathyroid hormone and high body weight.

McCarron DA Reusser ME. Body weight and blood pressure regulation. Am J Clin Nutr 1996; 63 (suppl 3): 423–425.

Bloomfield RL Young LD Zurek G Felts JH Straw MK. Effects of oral calcium carbonate on blood pressure in subjects with mildly elevated arterial blood pressure. J Hypertens 1986; 4 (suppl 5): 351–354.

Belizan JM Villar J Pineda O Gonzalez AE Sainz E . Reduction of blood pressure with calcium supplementation in young adults. JAMA 1983; 249: 1161–1165.

Moutquin JM Garner PR Burrows RF Rey E Helewa ME Lange IR . Report of the Canadian Hypertension Society Consensus Conference: 2. Nonpharmacologic management and prevention of hypertensive disorders in pregnancy. Can Med Assoc J 1997; 157: 907–919.

van den Elzen HJ Wladimiroff JW Overbeek TE Morris CD Grobbee DE. Calcium metabolism, calcium supplementation and hypertensive disorders of pregnancy. Eur J Obstet Gynecol Reprod Biol 1995; 59: 5–16.

Levine R DerSimonian R. Effects of calcium supplementation on pregnancy-induced hypertension [letter]. JAMA 1996; 276: 1387.

Roberts JM D'Abarno JD. Effects of calcium supplementation on pregnancy-induced hypertension [letter]. JAMA 1996; 276: 1386–1387.

Belizan JM Villar J Bergel E del Pinto A Di Fulvio S Galliano SV . Long-term effect of calcium supplementation during pregnancy on the blood pressure of offspring: follow up of a randomised controlled trial. BMJ 1997; 315: 281–285.

Calcium supplementation during pregnancy could reduce not only the risk of hypertension in the mother but also level of blood pressure in the offspring. Results of this study showed that children aged 7 years whose mothers had been administered calcium supplements had systolic blood pressures 1.4 mmHg lower than did children whose mothers had not. Systolic blood pressure in children with body mass indexes above the median were even reduced by 5.8 mmHg relative to those in children of control mothers.

Bauer UE Mayne ST. Do ethnic differences in dietary cation intake explain differences in hypertension prevalence? Results from a cross-sectional analysis. Ann Epidemiol 1997; 7: 479–485.

Ford ES. Race, education, and dietary cations: findings from the Third National Health and Nutrition Examination Survey. Ethn Dis 1998; 8: 10–20.

Davis IJ Grim C Dwyer K Nicholson L Dwyer J. The effects of calcium supplementation on ambulatory blood pressure in African-American adolescents. J Natl Med Assoc 1996; 88: 774–778.

Lyle RM Melby CL Hyner GC Edmondson JW Miller JZ Weinberger MH. Blood pressure and metabolic effects of calcium supplementation in normotensive white and black men. JAMA 1987; 257: 1772–1776.

Johnson NE Smith EL Freudenheim JL. Effects on blood pressure of calcium supplementation of women. Am J Clin Nutr 1985; 42: 12–17.

Cappuccio FP Markandu ND Singer DR Smith SJ Shore AC MacGregor GA. Does oral calcium supplementation lower high blood pressure? A double blind study. J Hypertens 1987; 5: 67–71.

Narayan KM Venkat Hanson RL Smith CJ Nelson RG Gyenizse SB Pettitt DJ . Dietary calcium and blood pressure in a native American population. J Am Coll Nutr 1998; 17: 59–64.

Reusser ME McCarron DA. Micronutrient effects on blood pressure regulation. Nutr Rev 1994; 52: 367–375.

McCarron DA. Diet and blood pressure-the paradigm shift. Science 1998; 281: 933–934.

The author strongly emphasizes the importance of studying diet as a whole in regard to the development of hypertension, rather than the roles of single nutrients. Within this context, it is argued that elevations of blood pressure that are often attributed to high-sodium diets are more likely the result of an inadequate intake of calcium-rich products, fruit, and vegetables.

Grossman E Vald A Peleg E Sela B Rosenthal T. The effects of a combined low-sodium, high-potassium, high-calcium diet on blood pressure in patients with mild hypertension. J Hum Hypertens 1997; 11: 789–794.

Sacks FM Brown LE Appel L Borhani NO Evans D Whelton P. Combinations of potassium, calcium and magnesium supplements in hypertension. Hypertension 1995; 26: 950–956.

One hundred and twenty-five subjects with mild or borderline hypertension were randomly assigned to combined fixed doses of calcium, potassium, and magnesium. No important effect of either regimen on blood pressure was observed after 6 months of intervention, which indicates these cation supplements do not exert a synergistic effect on blood pressure.

Preuss HG. Diet, genetics and hypertension. J Am Coll Nutr 1997; 16: 296–305.

Matkovic V Ilich JZ Andon MB Hsieh LC Tzagournis MA Lagger BJ . Urinary calcium, sodium, and bone mass of young females. Am J Clin Nutr 1995; 62: 417–425.

Kotchen TA Kotchen JM. Dietary sodium and blood pressure: interactions with other nutrients. Am J Clin Nutr 1997; 65 (suppl):708–711.

Gruchow HW Sobocinski KA Barboriak JJ. Threshold effects of dietary calcium on blood pressure. J Hypertens 1986; 4 (suppl 5): 355–357.

MacGregor GA Cappuccio FP. The kidney and essential hypertension: a link to osteoporosis? J Hypertens 1993; 11: 781–785.

Cappuccio FP Markandu ND Beynon GW Shore AC MacGregor GA. Effect of increasing calcium intake on urinary sodium excretion in normotensive subjects. Clin Sci 1986; 71: 453–456.

Criqui MH Langer RD Reed DM. Dietary alcohol, calcium, and blood pressure: independent and combined effects on blood pressure. Circulation 1989; 80: 609–614.

Wise KJ Bergman EA Sherrard DJ Massey LK. Interactions between dietary calcium and caffeine consumption on calcium metabolism in hypertensive humans. Am J Hypertens 1996; 9: 223–229.