Blood Pressure and Salt: What is the Connection?

Digital blood pressure cuffWhen blood pressure begins to rise, the advice always seems to start with reduce salt intake. While this can be good advice, it fails to consider the complexity and possible other causes of elevated blood pressure. Risk factors for high blood pressure, also known as hypertension, includes:

  • Sedentary lifestyle
  • Excessive sodium intake from processed and fatty foods
  • Low potassium intake
  • Being overweight or obese
  • Excessive alcohol intake
  • Smoking
  • Age greater than 60
  • Race – African American adults are at greater risk than Hispanic or Caucasian adults.
  • Certain diseases or medications

If high blood pressure is caused by another disease or condition, it is termed secondary hypertension. If there is no identifiable cause found, it is termed primary hypertension. Primary hypertension is the most common form and can be related to the risk factors above.

To understand the risk for hypertension, we must understand the physiology of blood vessels. The pressure inside the blood vessel is regulated by hormones that control the blood volume and pressure. When the blood volume increases so does the pressure. Coronary artery disease can also increase pressure inside the blood vessel due to constriction. When the diameter of the vessel wall narrows due to hardening of the arteries (loss of elasticity) or plaque build-up, it increases the pressure. Over time this can lead to more damage of the arteries and gradual increase in blood pressure. High blood pressure is a major risk factor for stroke and heart disease. Unfortunately, there are approximately 75 million people in the U.S. living with high blood pressure.

So, how do we treat high blood pressure? Lifestyle factors should be the first consideration unless blood pressure is dangerously high. If this is the case, medications and/or hospitalization may be required. But for slightly elevated blood pressure, making a few lifestyle changes can go a long way. Weight loss will help if you are overweight or obese. Exercise can also improve blood pressure over time. But be cautious about exercising if blood pressure is very elevated as exercise will make it go up. Avoid tobacco and excessive alcohol intake since these will make hypertension worse. Stress reduction can also help. Dietary changes include reducing intake of processed foods that are high in sodium and fat and eating more fruits and vegetables rich in potassium. Potassium seems to be protective against the effects of excess sodium. Diets such as the Mediterranean or DASH diet are known to reduce blood pressure and heart disease risk.  Some studies also found that getting adequate magnesium and calcium can improve blood pressure. Supplements may be beneficial but nutrients from food is always best.

The question remains however, how much sodium is too much? Americans consume 3,400 mg of sodium per day on average. Current guidelines recommend no more than 2,300 mg of sodium per day. The American Heart Association has lowered the guideline to no more than 1,500 mg of sodium per day for those at risk of heart disease. Some researchers argue that recent studies show limiting sodium too much may do more harm than good. According to them, a very low sodium diet increased the risk for heart disease. Several studies confirm reducing sodium intake improves cardiac risk factors, however the question remains how much should sodium be reduced? We know sodium is necessary for the body to work properly. We do not know for certain how much sodium is needed. Until we can determine this for certain, my advice is “sodium in moderation”. And remember, there is no “one-size-fits-all” when it comes to nutrition. You are an individual so listen to your body and stay healthy!