Since graduating from medical school in 1989, I have come to the conclusion that much of what I was taught was wrong. In fact, at my medical school graduation, the dean said, “Fifty percent of what we just taught you were wrong, your job is to figure out which part was correct and which was incorrect.” When medical students come to my office, I always encourage them to question everything I tell them and, furthermore, to question what they have been taught.
I was taught in medical school that a lowered salt diet was a healthy diet—for everyone. Furthermore, it was drilled into my head that anyone with heart disease, particularly heart failure, should limit salt in his/her diet. In fact, it is still standard-of-care for a cardiologist to tell his/her heart patient to limit salt in their diet. This is especially true when the patient is suffering from heart failure.
So, does limiting salt in the diet of a patient with heart failure result in a better outcome?
A recent study (Journal of the American College of Cardiology: Heart Failure. Vol. 4, No. 1, January, 2016) sought to evaluate the impact of sodium restriction on heart failure outcomes. The authors enrolled 902 patients with heart failure and followed them for 36 months. Based on the sodium intake, the subjects were classified into sodium restricted (<2,500 mg/d) and unrestricted (>2,500 mg/d) groups. The primary outcome was death or hospitalization from heart failure.
Most Americans consume about 3,300 mg/day of sodium.
Results: Sodium restriction was associated with a significantly higher risk of death or heart failure hospitalization of 85%. According to this study, as compared to those who do not restrict their salt intake, for every six subjects that restrict their salt intake, there will be one increased death or hospitalization for heart failure. The authors concluded, “In symptomatic patients with chronic heart failure, sodium restriction may have a detrimental impact on outcome.”
Comment: Salt is the second major constituent in the human body, next to water. If doctors are going to suggest limiting the second major constituent in the body they should have good, solid data available to back up that recommendation. I have tested thousands of patients for their salt levels and I have found that the vast majority–over 90%–are salt deficient.
Folks, there has never been good, solid data that limiting salt in the diet of heart patients is beneficial. Yes, there have been some studies showing a benefit. However, there have been many other studies that have found the opposite conclusion.