How much sodium (mg) is a non high blood pressure person allowed a day and if Diabetic ?

My boyfriend is 58 years old and weighs 250 lbs and is oonly 5'10" and has a large belly that  looks like a beer belly, but he doesn't drink. Almost everything he eats has a lot of sodium-pickles,olives,muchrooms,chips. I thought since he eats a lot of salads and is not loosing weighjt, the sodium makes him retain liquids, so I started reading labels and I am confused as how much is too much per day????  He is  a borderline Diabetic and controlling the sugar by diet only. Everything I pick up (cans) and look at the label, and the quanity per the serving size seems high and I would like to know what we should consider in our diets?

Thank you for any advice,

Carole Yasman