One of the unfortunate realities of cooking is that once you add salt, there is no way to get it back out. Even so, all is not lost if you over-salt a meal. If this has happened to you, do not panic. There are options for saving the meal.
Dilution is your friend
Under normal circumstances, the last thing you want for many dishes is to water them down. In a situation where you have added too much salt, that is exactly what you want to do. Note: This method works best for soups and sauces.
Fix your over-salted soup or sauce by adding water. Do not add a lot all at once. Instead, add the water in increments and taste after each addition until you reach the desired level of saltiness. You can then add other ingredients to increase the other flavors and get the dish back to the right consistency. This solution does involve you cooking more food, but at least you will not have to throw out the whole dish.
If you are cooking meat and added too much salt, the solution may be as simple as rinsing it under running water. Simply pat the meat dry once you are done rinsing it, add your desired spices and finish cooking.
The use of starch is a well-known way to counteract excess salt. Adding potato to a dish works in two ways: the potato absorbs some of the salt and can be removed before serving, or you can leave it in to dilute the salt thus lowering the salt level. Keep in mind that this works best for dishes that are a little too salty; a potato may not do much if you have added a large amount of extra salt.
Add a creamy component
Adding a creamy element cannot only dilute the salt, it can provide a distraction from it and make the dish seem less salty. Sour cream can work with many Latin American dishes and heavy cream can work in some soups. Making a dish creamier does not necessarily involve the addition of dairy as certain dishes can benefit from the addition of coconut milk or even avocado.
Increase the acidity
One of the most popular solutions for over-salted food is to add acidity. This can be tricky as salt and acid can actually enhance each other in some dishes. There are some cases where increased acid can and does help, but exercise caution when using this method.
Sweetness and saltiness can counteract each other in some dishes, so sugar or honey can be an option. Be careful with the amount of sugar that you add lest you affect the overall flavor profile of your dish.
Note: As with the potato solution above, adding sweetness only works if your dish is just a little too salty. If it is way too salty, you will have to add a large amount of sugar to balance it out. Too much sugar will ruin most dishes.