Canned foods often contain a tremendous amount of salt because bacteria are much less likely to thrive in high salt environments. This allows foods to have a long shelf life but, unfortunately, exposes people to very high sodium levels in their foods. Try to avoid canned foods as much as possible, particularly if you have high blood pressure and are trying to limit your salt intake. Do not eat food that comes from a damaged can. Cans that have bulges in them are generally full of gas-producing bacteria that has caused the can to get ‘bent out of shape.’ Throw out any can that looks suspicious.
If you choose to can your own food, take seriously the admonition that the jars and tops must be boiled in advance of beginning the canning process. This eliminates bacteria from the jars and makes it less likely your product will end up making you sick. Use approved old-school Bell jars, and make sure they seal properly.