Sodium is one of the largest contributers to hypertension; or high blood pressure. That's because sodium pulls water into the blood vessels (remember osmolality from science class?) and forces the heart to work much harder to pump the blood throughout the body. Just a little bit of hypertension can equal a lot of heart damage over, say, 40 or 50 years. Additionally high blood pressure can cause damage to the blood vessel walls, creating little nicks and pockets that collect residue and form blood clots. Between these two well-studied mechanisms of consuming too much sodium; salt is one of the leading killers and is involved in the etiology of many chronic diseases.
Sodium plays a role in and is a risk factor for stroke, heart attack, congestive heart failure, peripheral vascular disease, among others. Research shows that billions upon billions could be saved for our health care system is Americans cut down on just 1 teaspoon of salt a day. You read that correctly... just a teaspoon.
Leading Sources of Hidden Sodium
That said and health risks advertised, what are some of the big salt contributers to the diet that isn't the obvious (hot dogs, canned soup, frozen dinners)?
Cheese - Most cheeses are very high in sodium, for sandwiches shop for low sodium items and save the specialty cheeses for nice occasions. And yes, I'm sorry this does not preclude pizza.
Tomato sauce - If there is one thing worth learning to make in the kitchen it's a good sauce from tomato paste, water, fresh tomatoes and spices instead of relying on the jarred ones that are packed with sodium.
Ketchup and salad dressing - If you have a family history of heart disease or other risk factors consider buying no salt options. Otherwise just remember to keep condiments in moderation.
Deli meats - Try to pick up no salt or low salt deli items as these are generally packed with sodium. There are so many flavorful options to pack onto your sandwich (my current obsessions are thinly sliced cucumbers and green peppers) there's no need for high sodium deli meats.
Hope this all helps! Happy shopping!