Calcium and High Blood Pressure
According to studies conducted by researchers at the University of CT, low calcium intake has been linked to higher blood pressure and the development of hypertension whereas high dietary calcium intake or calcium supplementation lowered the BP.
Many scientists have found significant and independent associations between high dairy products and dietary calcium intakes and lower blood pressure among middle-aged men. Dietary calcium is an important factor for blood pressure via its effect on calcium metabolism.
Calcium is the most abundant mineral present in the human body.
Calcium has many functions. It is needed
- to support the body structure
- for muscle contraction
- blood vessel contraction
- blood vessel expansion
- hormonal secretions
- secretions of enzymes
- sending messages through the Central Nervous System
Sources of Calcium
All dairy products including milk, cheese and yogurt contain high amounts of easily absorbable calcium. Leafy vegetables, nuts and oilseeds, and sardines are also rich sources of calcium. Although most grains are not high in calcium they do contribute significant calcium to the diet due to their frequent consumption. Many foods including fruit juices are also fortified with calcium.
Action of Calcium
High levels of intracellular calcium increase vascular smooth muscle tone, peripheral vascular resistance, and responsiveness to the sympathetic and RAS systems, actions that elevate blood pressure. Paradoxically it is low not high calcium intake that stimulates an increase in parathyroid hormone. This leads to calcium mobilization from the bone, increased intestinal calcium absorption, decreased renal calcium excretion, increased intracellular calcium concentration and subsequently high blood pressure.
Some studies including those on the DASH eating plan have reinforced the importance of a diet high in calcium together with other minerals as having a beneficial effect on blood pressure. Hence a diet rich in fruits and vegetables with optimum amounts of whole grains, dairy products and nuts and oilseeds with its high content of dietary minerals has a beneficial effect on blood pressure.
