Low carb diets are popular. How good are they? How healthy are they? It all depends on what you know about the difference between different types of carbohydrates.

Common table sugar represents 20 to 25 percent of the daily caloric intake of Americans who live on the typical "All American" processed food diet. In the early 1800s average sugar consumption was about 12 pounds per person a year. In 1997, it was 152 pounds per person. Is that too much? You bet it is. It's making us old before we need to be.

Do we need carbohydrates? No, we don't. They are non-essential to the human diet. We do need water, fat, and protein. It is possible to survive for long periods without carbohydrates providing fat and protein needs are met. Fat and protein are broken down to make building blocks of carbohydrates as food and energy. This is something the carb-rich processed foods industry doesn't tell us.

Regardless of what is known about carbohydrate needs, we continue to consume massive quantities of carbohydrates. Therefore, it's important to know which carbs are better than others. It's simple: All carbs are broken down into sugar in the body. The key is the rate and the amount that determines the level of sugar in the blood.

Complex carbs such as green leafy veggies, brown rice, potato, whole grain products, and fruits break down slowly. The result is a gradual rise and fall in blood sugar. It is generally understood that most complex carbs are good for you.

Refined, simple carbs such as cake, ice cream, cookies, breakfast bars, so-called cereals, and refined grains break down quickly in the body. This causes rapid elevation of blood sugar levels. These are not good for your health.

It should be understood that while refined carbs should be avoided because they are harmful, some complex carbs such as potatoes are not good because of their relatively fast breakdown.

How do you determine which carbs are really good, and what to avoid? Simple. Become familiar with something called the "Glycemic Index" of foods. When you look at a glycemic index for foods, bear in mind that the lower the rating, or number, the slower the digestion and absorption process and the better it is for your health.

As useful as the glycemic index is, you will need to learn which foods are good for you.. For example, a cup of low fat ice cream has a glycemic index of 50, which is lower than the glycemic index of a baked potato. That's because the glycemic index rating of a refined sugar product is lower than that of a starchy food! So, learn to discern the difference between refined sugars and everything else. Just assume that if it's made in a factory, it's suspect!

Here are some glycemic index numbers for some popular food choices: Baked Potato: 85; Cheerios: 74; Fanta soft drink: 68; Cheese pizza: 60; Banana: 54; Sweet potato: 54, Low fat ice cream: 50; Carrots: 49; Grapefruit juice: 48; All-bran: 42; Spaghetti: 41; Apple: 38; M&Ms (peanut): 32; Peanuts: 15; Yogurt, lot fat, artificially sweetened:14.

You can see from the above how misleading, yet useful the glycemic index can be.

The bottom is this: Do your homework. Don't rely on advertising or uninformed advice of well meaning friends to give you guidance about healthy eating. Making educated choices about what you put into your body puts you in the drivers seat and allows you to be in charge of how healthy you are, and how quickly or slowly you age.