SALT: Friend or Foe?

As with everything we need, there’s a “goldilocks zone” for salt. Too much causes some problems, and too little causes other problems. We’ve known for a long time that excess salt drives high blood pressure: that’s why salt has got a bad rap. Many people have cut back on it, but we notice that very few of our patients are aware that it’s a problem if you cut back too much. Here’s why.

Table salt is a very simple molecule: It is sodium chloride. One atom of sodium attached to one atom of chlorine: just two elements, making up a tiny, but vital, molecule. Sodium is essential for cellular function and therefore for life, and so from our earliest history humans and other mammals have been drawn to seek salt.

Sodium is needed to regulate the volume of water in your cells: they must contain enough fluid to house all those crucial biochemical reactions that keep you alive, but not so much that the cells swell and burst. The mechanism that does this is the sodium-potassium pump, which is embedded in your cell membranes, and pumps sodium and potassium ions in opposite directions.  

Another effect of this pumping action is to create a minute voltage across your cell membranes: the electrical charge on one side of the membrane is different from the charge on the other side. This sets things up to allow all sorts of other necessary molecules to move in and out of cells, and is so important that in some cells, 75% of their energy is used on this pumping system.

Salt was used historically as a natural preservative: think salt fish, or pickles in brine. It has the ability to draw water out, which reduces the growth of bacteria, and it has other antibacterial properties too. It also has flavour-enhancing properties, which is why so much of it is used in processed foods. 

If your diet is high in processed or ultra-processed foods, you are more than likely getting more salt than you need.

If you eat out, it’s better not to add salt to your food: the chef was paid to get it right, and restaurants are often on the generous side with it. Some people get into the habit of picking up a salt-shaker and shaking it the same number of times over their meal, regardless of whether it is needed or not. Researchers discovered that the biggest difference in the amount of salt people ate in different circumstances was not the flavour of the food, but the size of the holes in the salt-shaker!

Too much salt can contribute to:

• High blood pressure

• Fluid retention

• Kidney stones

• Osteoporosis (due to calcium loss) 

However, there is such a thing as not getting enough salt. If cooking 100% from scratch, you will need to add a pinch of salt, as most natural foods may not contain as much as we need. If your blood pressure is a little low, and you don’t use much salt, adding some salt to your food usually helps. If you are someone who perspires a lot, whether through work or exercise, you will also need a little more.

Too little salt can contribute to:

• Low blood pressure

• Dizziness on standing

• Muscles feeling weak

Table salt often has iodine added - and you may be surprised to hear it sometimes contains added sugar. Himalayan pink and grey Celtic salt as well as other naturally gathered salts have trace minerals in them, and here the clue is in the name: they are minerals we need in trace amounts, and table salt only contains iodine, but none of the rest of them!

We need a minimum of ¼ teaspoonful of salt a day for health. Most people in the western world underestimate how much salt they are eating, and are consuming much more than that.

But do stay attuned to your body’s needs: if you taste something and think “this needs salt!”, it may be because you need salt. Don’t think of salt as the bad guy: like so many things it only causes problems in excess.