Thanks to my blood pressure medicine being made stronger, I am determined to get it down by diet. I never use a salt shaker but i want to know what foods are high in sodium to avoid them. Yes, I know most boxed items are but I am still wanting the info.
A good place to start is reading all the labels. I’m not sure they’re entirely accurate, but they’ll give you a good general idea. Some of the foods that are shockingly high in sodium are canned baked beans, canned spaghetti, canned stew, canned spaghetti sauce, canned soup (basically everything in a can is suspect), and cottage cheese. There is a low-sodium cottage cheese available in my supermarket; I assume there would be one in yours, too. Cottage cheese was a shocker when I started eating low-sodium; I assumed that a food always associated with healthy eating would be low sodium, too, but it isn’t.
ETA: Second source of extremely high sodium foods is eating out. I’m finding it very difficult to eat low-sodium anywhere except at home.
Just about anything canned that isn’t labeled ‘low sodium’ is high sodium. You’ll get way less salt in your diet by using the low-sodium or sodium-free versions of same, then adding seasonings yourself. Better yet, when it comes to things like canned veggies, use frozen (if you’re using canned for the convenience/cost benefit) and add your own seasonings. This allows you to season with more than salt, like dried herbs, a little pat of butter (it’s amazing how much difference a little fat can make!), fresh herbs, etc.
Also, when it comes to things like vegetables, if you’re used to using canned, try using fresh or frozen then preparing them differently, like stir-frying with a little low-sodium soy sauce and ground ginger.
Best of all, as Cat Whisperer says, read labels!
I thought of another thing; instead of putting soya sauce on my rice (even the low sodium version is still high), I’ve switched to balsamic vinegar. If you like the taste (like I do), great. If you don’t like the taste, oh well - you tried. 
Basic food science uses either salt or sugar in processed foods to lower what is refered to as water activity. The salt or sugar combination ties up the moisture in a way that keeps it unavailable for microbial growth and extends the shelf life.
You can search for the term ‘water activity’ if you want to learn boring stuff about the food you eat, but it will help answer the inevitable questions about “why in the world don’t they just stop adding so much salt?”
You have to be careful when buying ‘low sodium’ processed food because the salt has just been replaced with sugar to lower the water activity. Salt is the first choice because it is much cheaper than sugar.
Reading the labels is good advice but keep in mind that if it is a processed food there is something in it controling the water activity that is probably bad for you.
Making you own food from fresh ingredients is really the only way to know what you are eating for sure.
Balsamic vinegar is a great way to add flavor to many things without adding sodium! And if you are making your own food, from fresh or frozen, remember: salt is a flavor enhancer. That means that a small amount can make the difference between “bland, no-flavor, I-can-only-taste-the-herbs” cooking and “wow, this is great seasoning!” cooking. But if you use the right seasonings, a small amount of salt is all you need!
ghardester raises some really good points about why there’s so much salt/sugar in processed foods. But when you cook for yourself, you don’t need all that. You only need ‘just enough’ to bring out the other flavors!
You may find it easiest to start logging your food using a website such as SparkPeople.com . You can set it up to show your daily intake of any nutrient you want.
Once upon a time, I set it up to track sodium. That lasted about a week… I was scared by how easy it is to eat too much 
another person chiming in with much the same answer…
Cook your own foods (say, tomato soup) instead of buying cans or eating in restaurants. Don’t add salt* until you’re going to eat it.
I was AMAZED at how much salt is in preprepared foods!
I cannot eat canned soups anymore… they taste icky.
*you can’t do this for baked goods, they need salt for their chemistry to work correctly.
Moving from IMHO to Cafe Society.
Rule of thumb: If it comes in a package, it has too much soduium. Just about anything labelled “low sodium” has either extra sugar or extra salt substitute added. Neither of which are much better for you.
Lemon juice, oils, and vinegars are your seasoning friend. Soy sauce is your mortal enemy. As are most pre-fab spice blends. So-and-Sos Cajun or grilling or whatever seasoning is mostly salt.
Start with base incredients and always use non-salt spices;your diet will be fine. And you’ll have no need for math or reading fine print.
Wrong. A small amount of salt during cooking will bring out flavors better and you won’t need to add salt at the table where you will often add more than you would get from pre-seasoning.
Oh, you beat me to it! I was going to post much this very thing.
I season before cooking, and we don’t have a salt shaker on the table. Actually, we don’t have a salt shaker at all. I have a Mediterranean Sea Salt grinder that I use during cooking. I also make good use of pepper (if you’re trying to cut down on salt, definitely use freshly ground pepper, if you don’t already. The difference is amazing), and herbs.
Concur. Adding salt during cooking pulls the seasoning into the food. Adding salt after cooking just salts the surface. Better flavor with less salt results from the former.
But yes, for the most part, avoid anything in a box, can, or restaurant menu.
Frozen dinners are surprisingly high in sodium also.
I agree with the salt during cooking, not after.
IIRC (and I may not), one of the ‘healthy’ frozen dinner lines (Healthy Choice? South Beach? I dunno) offers some selections that are low in sodium. However, as previously noted, if it’s a convenience food that’s low in sodium, it’s either high in something else that’s bad for you, or it’s tasteless, or worst of all, both.
If you need a low-sodium diet and need the convenience of frozen foods, make your own foods, as stated above, and freeze them in those GladWare containers or some such.
When my mom had to start watching her sodium intake, the dietician specifically warned about Chinese and Mexican restaurant food.
Cured and smoked meats (e.g. ham and salami) are usually very high in sodium.
Some cheeses are high in sodium. Blue cheeses (Roquefort, for example) are among the worst. Swiss-type cheeses such as Emmenthal and gruyere are usually fairly low in sodium. Cottage cheese can be surprisingly high in sodium (it doesn’t taste salty, but can have 900 mg per cup).
I’ve noticed lately that every supermarket I go to has both no salt added canned beans and no salt added canned tomatoes. Since I tend to make a lot of soups and stews (bachelor cookin!), this is a real boon. I still add salt on my own upon occasion, but I know it’s not as much as the manufacturer would.
Canned beans and soups are the biggies. If you buy canned vegetables, stop and start buying frozen. Rinse canned beans thoroughly and get or avoid canned soups all together. If you must, get low-sodium soups (which are actually just “regular” sodium, in terms of what’s healthy for you).
Also, if you buy any kind of chicken, veggie, or beef stock in a can or in an aseptic container, be sure it’s low sodium. Trader Joe’s has an extremely low sodium free range chicken stock that’s very good.
Bottled salad dressing is also a likely offender. Penzey’s has a strong line of no-salt spice mixtures; so check out your spice mixtures and adjust accordingly.
If you’re going out to eat, check out Eat This, Not That! to see if your restaurant’s menu has been dissected. If it has been, you can jot down or save in a text message on your phone a list of low sodium dishes.
Reduced sodium cans of soup can be OK. I just had one the other day that had 300 mg of sodium.
Meijer brand condensed chicken noodle, however, is 1100 mg of sodium! Yikes!
See, this is why discussing things is a good idea - my brain neglected to make the leap from using balsamic vinegar in one thing to many other things.
I haven’t seen the canned beans yet, but I use the no salt added tomatoes and tomato sauces all the time. I often dilute a high sodium canned food like spaghetti sauce with no salt tomato sauce to cut the sodium in it.