I think that is so individual and dependent on people's senstivities.
If I eat sugar, it will be a 3 pound gain on the scale without fail the next day.
If I eat homemade salsa - I will gain a pound or two.
If I eat sauerkraut, I will gaine a pound.
And I do not eat a low sodium meal. I don't eat processed foods, so my sodium isn't sky high from that, but I do add salt to my foods when cooking, but tend to undersalt and will then salt my food at the table. So, these are things taht get me even though I already eat salt.