There is evidence that calcium helps lower your blood pressure, but there is also evidence that it doesn't. According to the National Institutes of Health, this may be due to differences between the study methods used to analyze the connection between calcium and blood pressure, as well as poorly designed studies. Calcium is definitely an essential mineral. Your body uses it to build strong bones and teeth and also to contract your muscles, widen your arteries and transmit nerve signals. Researchers are still learning about just how it affects your blood pressure. Do not take supplements without first consulting your physician.
Dairy
Consuming low-fat dairy products may protect you against high blood pressure, although it is unclear if calcium is the protective agent. In a January 2009 article published in "The British Journal of Nutrition," a group of Spanish researchers write that in a study analyzing the diets of 2,290 participant, the consumption of low-fat dairy products appeared to protect against the development of hypertension. The study population consisted of men and women ages 55 to 80. Study participants also consumed less alcohol, fewer calories and less protein.
Vegetarians
Vegetarians have lower rates of hypertension than the general population. They also have lower rates of diabetes and obesity, both risk factors for developing hypertension. In a July 2009 position paper, the American Dietetic Association writes that lacto-ovo-vegetarians consume as much or even more calcium than non-vegetarians. Lacto-ovo-vegetarians consume egg and dairy products.
Older Women
Older women may benefit more from calcium than other groups. In a study of nearly 30,000 women ages 45 and older, higher intakes of calcium and vitamin D decreased their risk for hypertension. The study results were published in the February 2008 issue of "Hypertension." The researchers concluded that dietary calcium may improve the balance between sodium and potassium in your body, may prevent your arteries from contracting, help with weight loss and may improve your sensitivity to insulin.
Concerns
It is possible to take too much calcium. Calcium supplements may interact with certain types of blood pressure medication, such as thiazide diuretics and calcium channel blockers. This interaction normally occurs if you are taking 1,500 mg or more of calcium. For adults ages 19 to 50, the highest tolerable calcium intake is 2,500 mg per day and 2,000 mg for adults age 51 and older. In higher doses, calcium can interfere with your body's absorption of iron or zinc, can cause constipation and can increase your risk of developing kidney stones.
References
- National Institutes of Health Office of Dietary Supplements: Calcium
- "The British Journal of Nutrition"; Low-fat Dairy Products and Blood Pressure: Follow-up of 2,290 Older Persons at High Cardiovascular Risk Participating in the PREDIMED Study; Estefania Toledo, M.D., Ph.D., et al.; January 2009
- "Journal of the American Dietetic Association"; Position of the American Dietetic Association: Vegetarian Diets; July 2009
- "Hypertension"; Dietary Intake of Dairy Products, Calcium, and Vitamin D and the Risk of Hypertension in Middle-Aged and Older Women; Lu Wang, M.D., Ph.D., et al.; February 2008
- MayoClinic.com; High Blood Pressure (Hypertension); Sheldon G. Sheps, M.D.; June 10, 2010
