If you have ever had an elevated blood pressure reading, your doctor likely has suggested that you lose weight, exercise, and reduce salt intake. The first two suggestions should be heeded without further thought, but the matter of dietary salt is a bit more complicated. We wouldn’t recommend that you ignore your doctor’s advice, but instead that you take a moment to learn a little more about what is a complicated question: how much salt do we really need?
What do experts say about sodium intake?
You probably already know that table salt is sodium chloride, NaCl, and that 40% of its mass is sodium. You might be surprised to learn that there is less than complete agreement regarding optimum daily sodium consumption:
- The American Heart Association has set a strict upper limit of 1,500 mg.
- The American Diabetes Association and the Academy of Nutrition and Dietetics both recommend consuming between 1,500 and 2,300 mg daily, depending on total caloric consumption.
- The United States Department of Agriculture suggests 2,300 mg of sodium daily.
What is perhaps even more surprising is that the science behind limiting dietary sodium is ambiguous, at best. After all, sodium, in tandem with potassium, plays a crucial role in balancing extracellular fluids. Too much sodium increases fluid retention, which drives blood pressure up, whereas too little can spawn a host of serious metabolic disorders:
- Low sodium drives up triglycerides and LDL cholesterol, both of which are risk factors in heart disease.
- Sodium-restricted diets seem to foster insulin resistance and metabolic syndrome, which in turn is related to obesity and type 2 diabetes.
- For type 2 diabetics, sharp restrictions of dietary sodium are inversely correlated with mortality: less salt, greater death rates.
What's the big picture?
What is missing here is the big picture, the one that embodies balance as a first principle and holds sodium in proper proportion with all other factors. Hypertension is a symptom, not in itself a disease, but it does have long-term consequences. Even at that, sodium restriction has no measurable effect on either incidence of cardiovascular disease or mortality.
Furthermore, a massive and especially well-designed study has shown that restricting sodium has very little effect, on average, in reducing either systolic (-5.39 mm Hg) or diastolic (-2.82 mm hg) pressure readings, even in the hypertensive patient. In normotensive individuals, reductions are all but nonexistent. Instead, a new paradigm for managing blood pressure has emerged, one that emphasizes carbohydrate reduction coupled with lots of natural plant and animal foods rich in potassium and magnesium. Refined carbs should be avoided altogether.
So, what should I do about sodium in my diet?
Moderation is key in sodium consumption. Avoid processed foods entirely, and you will be able to make the focus exclusively added table salt. Do not measure or weigh salt. Instead, add it sparingly for flavor and eat a broad spectrum of natural foods. Lose excess weight: a reduced carbohydrate diet is your best choice.
As always, talk to your doctor about this first, especially if you are currently under treatment for hypertension. Salt is essential; it is not the enemy. Lack of knowledge and unwillingness to implement a sensible, balanced plan are the enemies, and you alone have full control over these factors.