For many people, excess sodium in the diet can contribute to high blood pressure and other adverse health effects. The daily recommended sodium intake falls between 1500 mg and 3000 mg, depending on how many calories you consume (about 1,000 mg of sodium per 1,000 calories).
Interestingly, according to the Mayo Clinic, only about 11 percent of the sodium in the average US diet comes from adding salt to the food. The majority of sodium, over 77 percent, comes from eating prepared or processed foods that contain salt. Unfortunately, fast foods are some of the worse offenders when it comes to high salt content (just add salt and you can cover up just about anything).
And even the sodium levels present in the public water supply can vary significantly from one area to the next. Yes, salt intake from just the water we drink. The New York city public water supply has one of lowest sodium levels of sodium in the country and Galveston, Texas has one of the higher levels of sodium (from the public records, not an exhaustive and conclusive study).
Here is a list of common food items with their associated sodium content. Some of the sodium levels in our everyday food may surprise you. For example, canned peas have over 100 times the sodium of raw peas.
Source: Sodium Content in Foods