In part one of this blog, I discussed the fact that salt is one of the most critical components of the human body. So how did we end up in a situation where salt suddenly became terrible?
It is hard to be sure but probably because it is possible to overload the system that dumps excess salt.
The kidneys can remove significant amounts of salt from the body for most people. Indeed, anyone eating a healthy natural food diet will not overload themselves; in fact, most of us need to add a little extra to our food. This is absolutely necessary if you exercise and sweat. Indeed in my office, I regularly see fatigued individuals despite the fact that they eat a healthy diet, exercise and have sufficient sleep. A few days of extra salt typically fixes the issue.
But of course, many people do not eat a healthy diet. They survive on easy-to-cook ready-meals, inexpensive restaurant food or straight-up junk food. You would be correct in guessing that these typically contain excessive amounts of salt and sugar coupled with an absence of fibre.
If this is your diet, it can overload your system with salt. The net result is water retention. Remember, water and salt need to be in a one-to-one ratio, so if you keep adding more salt than you can get rid of through the kidneys (and you never sweat because you don't exercise), you will have excess water in the body.
Some of that water will be in your blood vessels or circulation. If you fill up your blood vessels to capacity, your blood pressure can increase.
So the evidence is that if you have normal or near normal blood pressure restricting salt will not lower it and indeed puts you at risk of having low body salt levels, along with altered metabolism of calcium and magnesium. So restricting salt, especially in hot climates or if you exercise, is a very poor plan. Indeed you need to replenish the salts you lost with electrolytes (a big word for salt). How much, half to one teaspoon per day?
If you have high blood pressure and a healthy diet, restricting salt probably won't make any difference. In fact, you can put yourself at risk by doing so. However, if you live on processed foods, aka junk food, ready-meals or restaurant food, you will most likely benefit from restricting your intake by removing any extra added salt from your meals. Better still, try to switch to a healthy diet which may lower your blood pressure by up to ten per cent.
A small number of us appear to have a poor or diminished ability to get rid of, or to use the correct term, excrete even small amounts of excess salt. I suspect that this tiny proportion of people has given rise to the fallacy that salt restriction is the best way to improve blood pressure. Hardly a reason to put the rest of the population at risk.
In summary, eat real food.
If you exercise or live in a hot climate, add salt to your food to replace the salt you lose in sweat. If you have high blood pressure on a healthy real food diet and don't add silly amounts of salt to your food, carry on. If you add lots of salt, try removing the extra for a week and see if it helps. If not, carry on as before. If you have high blood pressure and live on junk, switch your diet. It will help and may well fix the problem.