In part four of my series, I hone in on four minerals that can truly influence your blood pressure levels. They are sodium, calcium, magnesium and potassium. Here is why:
In the U.S., the average sodium intake is five grams a day with some part of the country consuming a much higher amount of 15 to 20 grams daily. High blood pressure subjects who keep a low-salt diet can expect an average systolic blood pressure reduction of 4.0-6.0 mmHg and a diastolic blood pressure reduction of 2.0-3.0 mmHg. In a recent meta-analysis of 167 studies, researchers found various ethnic groups could all reduce their levels by lowering salt intake. The conclusion: sodium reduction dropped blood pressure by about 3.5% for those with high blood pressure.
Calcium supplements for high blood pressure yield inconsistent results. However, there is a dramatic effect for pregnant women — it could prevent the hypertensive disorders known as “preeclampsia” and “eclampsia.” In a meta-analysis of 13 studies involving 15,730 women who were given at least one gram of calcium daily during their pregnancy, calcium supplements reduced the risk of pre-eclampsia and preterm birth by 50%.
The blood pressure-lowering effect of magnesium is less consistent than the effects seen with sodium or potassium supplementation. In a meta-analysis of 20 studies involving 1,220 individuals, magnesium supplements led to a 4.3-mmHg reduction of systolic blood pressure and 2.3-mmHg reduction of diastolic blood pressure — for each daily increase in dosage of 10 millimoles (mmol) per liter.
The recommended daily intake of potassium is 4.7 grams a day. However, the average intake of U.S. women and men is 2.3 and 3 grams each. In a Chinese study, 150 individuals with high blood pressure (age 35-64 years) were randomized to receive 60 mmol potassium chloride supplement or placebo daily for 12 weeks.
Potassium supplements led to a fall in systolic blood pressure by 5.0 mmHg (range: 2.13 mmHg to 7.88 mmHg) without any diastolic blood pressure changes. But, in an Italian study on 104 high blood pressure subjects (age 41-65 years) given 30 mmol a day of potassium for four weeks, there was a fall in both systolic and diastolic blood pressure by 12.2 mmHg and 2.2 mmHg, respectively. Experts say that, in high blood pressure individuals, the additional intake of potassium by 600 mg a day would result in a systolic drop of 1.0 mmHg and a diastolic drop of 0.52 mmHg.
Potassium-associated blood pressure reduction significantly lowers the risk of stroke, coronary heart disease, and other cardiovascular events. If you get 4.7 grams a day of potassium, there may be a decrease of up to 15% in your risk of stroke and up to 11% in your risk of heart attack.