What is the purpose of eating an adequate level of sodium?
All words below in italic are quoted from the source [SALT] unless otherwise stated.
Man cannot survive without [...] sodium. Before salt became a trading commodity early man got all the sodium he needed through eating fish, shellfish and meat (p26)
What is a reasonable daily intake of sodium?
2.5 grams of sodium a day (p81) as the recommended intake of a sedentary adult.
Such level needs to be increased when perspiration increases as perspiring translates into a loss of sodium which has to be replaced.
Where is sodium naturally found?
Typically sodium is ingested when we eat salt. Some foods however do contain sodium in various amounts.
For example, fish and seaweed contain more sodium than other food types. Example: On a tin of tuna chunks in springwater sodium per 100g is listed as: 178mg
In our experience...
Based on a diet where nearly no processed food is eaten, I do not have to consider the salt added to processed foods.
I use a container as a guide with a measure corresponding to a quantity of 6g of iodised rock salt. This would be my maximum quantity for a normal day.
When on our 70kms to 100 kms bike ride, I take extra rock salt which I suck on demand.
How much salt is too much for me? I rely on my body to let me know: whether weakness in the legs when bike riding, or feeling a bit off,
my tongue if pale is a good indication that I need salt.
This seems to work for me: I used to dehydrate a lot as a toddler, as a tennis competitor as a teenager, and up until the beginning of this new diet around 2013.
Since then 40+ degrees temperature on a bike ride are no longer a dehydration risk (although not necessarily a pleasant temperature to ride in either :)
Try and find out what works for you given your activity level, and the type of processed food ie hidden salt/sodium you already eat.