The NHS recommended salt intake has no bases in science (just like the eat well plate!) some studies show that people live longer when they have about double the recommended salt intake. This is still a lot less then someone eating fast food etc every day gets, so lots of people do have too much salt. If you are cooking all your own food you are very unlikely to be having too much salt.
Lots of people eating low carb find that a stockcube in a mag of hat water two times a day helps them as it provides a little more salt. It seems that the body needs a
little more salt on a low card diet.
LoSalt sounds like a good option for getting potassium but I would still have the stockcubes to get enough sodium. A spoon of Marmite in a mug of hot water will give B12 as well as salt.
Clearly we need to drink enough water, but without salt, our body will not take on the water – hence the recommendation to have 5g of salt 1hr before a long run, with 0.5l of water 30 minutes before the run. (LoSalt would be ideal for this as potassium is lost as well when we sweat.
Sodium results can often look normal even if you are not having enough, as the body chooses dehydration over having to low sodium. If you kidneys are working well, they will remove any excess salt.
I have seen claim that “slow mag”is needed by some people on low carb to stop cramps – details in
The Art and Science of Low Carbohydrate Living on how to get the dose right.