Sorry I'm late to the party on this one...
The issue of salt is very near and dear to my heart (literally).. I spent years as a salt junkie, putting WAY too much on just about everything. On the surface, Laura, you're right.. Salt is low calorie and no fat, so really the only way we lose or gain through salt is by water retention.. However, as the article below plainly shows, salt is a killer (also literally) when it comes to the foods we put in our body.. Lower your salt intake by eating healthier foods and you'll not only lose weight but also improve your general health..
There's no way to eliminate salt from our diets completely, nor should we.. Our bodies need what it gives, but as a society we consume many times the needed amounts on a daily basis..
Laura, eliminating canned foods is much easier than you think it will be. The only canned food my family now regularly ingests are "kitchen cut" green beans because for some reason, that's the only way my son will tolerate them. The trick is to flush the can out with fresh water several times to reduce the salt content. Add to that the fact that most canned veggies also have frozen counterparts that include much less salt. When it comes to soup, try making your own. There are some new very low-to-no sodium stocks and broths out there, which will make soup making lot easier.
Try making your own spaghetti sauce using low (50 mg or less) canned tomatoes. It may seem like a pain at first, but if you add in your own spices, it can be really tasty. It's a trial and error thing, honestly. If you REALLY need more salt, use a few dashes of Morton's lite or "NoSalt".. But be careful with the "NoSalt".. It's basically pure potassium and has a VERY strong taste.. A little goes a LOOOONG way...
Ok.. back to the basic question of how salt affects weight loss... Reading between the lines here is the dirty secret that even "healthy" processed foods are a killer... You CAN remove a lot of the processed foods from your diet, from cheeses and lunch meats to the frozen diet stuff, our bodies don't need all the extra crap these foods provide us.
This article comes from www.caloriesperhour.com
How Salt Affects Your Weight
Diet and Weight Loss Tutorial
Salt does not cause your body to gain or lose fat. In fact, salt has no calories. High consumption of salt only results in temporary weight gain as it causes your body to retain water. Conversely, low consumption of salt can result in temporary weight loss as it causes your body to expel water.
It is interesting to note that many crash diets which boast quick weight loss rely on foods with little or no salt content. The weight loss is mostly water, and as soon as you eat foods containing salt again you regain the weight.
A Word of Caution
Our opening paragraphs would lead you to believe that salt is of little concern in regards to long-term weight loss. In fact, a diet high in salt content can not only affect your blood pressure (see below), but is typically associated with weight gain.
The reason is that high levels of salt in our diets usually come from calorie dense, fiber poor, processed foods, like those found in fast food and restaurant meals, as well as on supermarket shelves. If you adhere to a low salt diet, it will likely consist of the lower calorie, healthier foods associated with weight loss.
Salt versus Sodium
We add table salt (sodium chloride) during cooking and at the dinner table to enhance the flavor of our food. Manufactures add it, often in great quantities, to return flavor to processed foods and help preserve them. But when we look at nutrition content, we look at sodium.
Though the terms are often used interchangeably, salt and sodium are not the same thing. Sodium, which is found naturally in most foods, accounts for approximately 40% of table salt. Therefore when salt is added to food, the sodium content increases by approximately 40% of the amount of salt added.
Why Salt Causes Water Retention
Our bodies rely on electrolytes, most significantly sodium and potassium, to carry the electrical impulses that control our bodily functions. In order for our bodies to function properly, it is important that the concentration of electrolytes in our bodies remain constant.
A high concentration of electrolytes in our blood triggers our thirst mechanism, causing us to consume adequate amounts of water to return to the proper concentration of electrolytes. This is one of the reasons bars provide free salty snacks like pretzels and peanuts. The salt causes us to become thirsty and purchase more drinks.
When we consume an adequate amount of water, our kidneys are able to keep the concentration of electrolytes in our blood constant by increasing or decreasing the amount of water we retain. The result of our retaining more or less water in our bloodstream can also affect our blood pressure.
The water moves beyond our bloodstream, too. Through the process of osmosis, water flows from a lower salinity environment to a higher one in an attempt to balance the levels of salinity. After we consume large amounts of salt, it is the water moving from our bloodstream into our skin that gives us that "puffy" look and makes it hard to get our rings off. Then, when we consume lesser amounts of salt, the same process works in reverse to remove the excess water from our bodies.
Salt and High Blood Pressure
Some people are "salt sensitive," which means that consumption of salt can increase their blood pressure. High blood pressure, or hypertension, is an important risk factor for both heart attack and stroke.
For information on high blood pressure, including methods of lowering it and recommended levels of sodium consumption, please visit the American Stroke Association and American Heart Association websites.