Minerals Calcium

It has become recognized relatively recently that changes in maternal calciotropic hormones and calcium metabolism (i.e., increased intestinal absorption and reduced urinary excretion) enable the fetus to be supplied with adequate amounts of this mineral, and that little change in maternal intake is needed. There is no correlation between the number of pregnancies a woman has and her risk of bone fracture, so the maternal skeleton does not serve as the calcium reservoir for the fetus. Thus, for the United States and Canada there is no increase in recommended calcium intakes for pregnancy and the AI recommendation remains at 1300mg/day for women aged 14-18 years and 1000mg/day for the 18- to 51-year-old group. In the United Kingdom, the recommendation is also that no increase in intake is required during pregnancy, although the level of intake for nonpregnant, nonlactating women is considerably lower at 700mg/day.

In a series of 14 randomized, controlled calcium intervention studies in different countries, increasing calcium intake in the range of 3752000 mg/day reduced maternal blood pressure and the risk of pregnancy-induced hypertension and preeclampsia by 30-40%, with a greater effect in populations that consumed diets relatively low in calcium. The multicenter Calcium for Preeclampsia Prevention trial on 4589 pregnant women in the United States found no such benefits of a 2000 mg/day supplement, presumably because of reasonably high usual intakes of the mineral. It is possible that women at higher risk of pregnancy-induced hypertension, such as those with very low calcium intakes or adolescents, may benefit from calcium supplementation.

The UL for calcium in pregnancy is the same as that for the nonpregnant woman, 2500 mg/day. This safe level is set based on documented cases of 'milkalkali syndrome,' in which there is high blood calcium, renal failure, and sometimes metabolic alka-losis as a result of chronic consumption of high calcium intakes.

Blood Pressure Health

Blood Pressure Health

Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...

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