I had another question that someone who is better at chemistry than I can answer. If I remember my high school chemistry correctly when you combine an acid and a base the reaction leaves you with water and a salt. Since baking soda is usually sodium bicarbonate when it mixes with an acid does it release sodium into your dish and if it does is it enough to be significant?
By definition a salt is what you get when you combine an acid with a base and the hydrogen in the acid is replaced by the metal (or cation) in the base. (NaCl is a salt, but there are many other salts.) There can be other by-products when you combine an acid and a base. (For example, combine vinegar and baking soda and you will get lots of carbon dioxide.)
According to the cardiology web sites, I’m supposed to count all forms of sodium, including things like sodium bicarbonate and the small amount of sodium present in flour. That’s why I just bought some low-sodium baking powder to try out.