Saturday, October 4, 2008

Questions About Sodium

I hear so many misstatements about sodium, including its relationship to weight gain, I'm taking the time to address the facts to clear some of the confusion. One of the first things to understand is the amount of sodium humans need on a daily basis, and then what the recommended limitations are. Once you have an idea of what the numbers mean you can make sensible decisions based on the facts you are reading on the food labels.

First of all, sodium is an essential element in the diet. We have sodium in our body and it must be kept within a specific concentration in our bloodstream for normal body functions. So we definitely need it. In fact, if a person were to try completely eliminating sodium from their diet, the consequences could be quite harmful--even fatal!

That said, the minimum recommended sodium intake is about 500 milligrams. Milligrams are the units found on food labels in regard to sodium so it's easy to find how much sodium is contained in any food with a label. Once you start reading labels you'll find that canned and processed foods do contain quite a bit of sodium. However, foods many people talk about being high in sodium (like soda, for instance, which somehow got a terrible reputation for being high in sodium and terrible for causing fluid retention) are not. Soda averages 25-50 milligrams of sodium--NOT a high source! Bread averages 120 milligrams of sodium. Baked goods will all have at least 100 milligrams of sodium because salt and baking soda (sodium bicarbonate) are used to make them. Again, not a number to worry about. Why?

Because the recommendations for sodium intake are to limit this mineral to 2400 milligrams per day. Two-thousand, four hundred milligrams each day. Now you can see that a food with 100 or 200 milligrams is not very high in sodium, even though we think of 100 as a high number. In this case, it's not!
Anyone with normal and healthy kidneys, normal blood pressure, and a good daily intake of fluid will be able to flush out all the excess sodium ingested during the day. Eating a hot dog one day is not a likely cause of any fluid imbalance or organ damage in a healthy individual--you usually find yourself more thirsty later on and naturally drink more water to help eliminate the extra sodium.

The problem is, the average sodium intake of most Americans is near 4000 milligrams of sodium daily, and some take in amounts near 10,000 milligrams each day. Over time, consuming large amounts of sodium can contribute to elevated blood pressure in some people. This, surprisingly, is rarely from people salting their food. A teaspoon of salt (the main source of sodium) contains 2000 milligrams of sodium. If you were to measure a teaspoon of salt into a shaker and use that to salt your food during the day, the average person probably wouldn't use most of it.

Then where does most of our dietary sodium come from? Start checking the labels on your canned food and frozen foods; start looking up the sodium content from fast food restaurants (frightening!); check out sodium content in processed foods such as lunchmeat (bologna, hot dogs), corned beef, pickles, and olives. Here is where you will find single servings that are providing 500 milligrams of sodium, 1000 milligrams of sodium and even more! One trip to a fast food restaurant can easily put you up to the recommended 2400 milligrams before you include anything else you eat all day! Look at a can of soup, a diet frozen dinner entree, a pizza. This is where Americans are getting their excess amounts of sodium.

It's not a bad idea to watch your sodium intake, and it is certainly a great idea to read labels. But both these efforts are wasted if you don't know what you're looking for or what the numbers mean. Stop worrying about the 40 milligrams of sodium in a diet orange soda when you're having it with a corn dog that contains over 900 milligrams of sodium. Stop worrying about the 240 milligrams of sodium in your high fiber breakfast cereal when you're consuming 800 milligrams in a can of soup for lunch! Don't even think of giving up your morning glass of milk because it contains 120 milligrams of sodium... especially when you pour diet Italian dressing on your salad at dinner to the tune of 470 milligrams of sodium! What about spaghetti sauce you use from a jar? Check it out--one half cup contains over 800 milligrams of sodium!

My point here is not to worry you about the amount of sodium you take in. My point is that a healthy, low calorie food that provides a concentrated source of nutrition should not be avoided because it contains a few hundred milligrams of sodium (like milk or cereal). Especially by someone who is going to have thousands of milligrams of sodium later that day in a sandwich of lunchmeat (which is also high in fat) or a chinese buffet (during which they are likely to consume far more calories than they need as well).

Finally, sodium does not contribute to or cause weight gain. If you eat a high sodium meal you will retain fluid weight until you have consumed enough extra water to flush out the extra sodium (yes, drinking more water will help flush out the sodium faster). So, yes, the scale will reflect a higher body weight for a number of hours. This has nothing to do with how much fat you are carrying, which is presumably what we want to lose when we want to lose weight! Your sodium intake has no effect on your body fat content, or on how difficult it is to lose fat weight.

For now, keep reading those labels, but first know what the numbers mean! Don't ignore the highest sodium foods with a low nutritional content (like a fast food breakfast sandwich with sausage or bacon and 820 milligrams of sodium) and then turn around and avoid a healthy choice (like low fat cheese) because it has 200 milligrams of sodium!

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