Carbohydrates are used as fuel for your brain to function well, as well as the primary source of fuel for the muscles in your body. Carbohydrates are various compounds strung together like beads on a string. Some of those compounds are sugar (glucose, dextrose, fructose), and some are fiber and starches. The more complex the carbohydrate (the more things are strung together) the longer it takes to be broken down and absorbed by your body. One of the simple carbohydrates is table sugar—which is two types of sugar (glucose and fructose) strung together. When you swallow it your body absorbs it quickly, causing a rise in your blood glucose level (glucose is a simple molecule of sugar). Green beans contain “complex” carbohydrates that take longer for your body to digest (break it down).

All carbohydrates are not bad

There is a vast marketing campaign offering low-carbohydrate meals at various restaurants, and “low-carb” food in grocery stores, leaving the impression that the lower the carbohydrate count in the food, the better off the meal. Sometimes those “low-carb” foods have more calories and more fat, making them a poor choice for losing or maintaining weight.

The key to losing weight is eating the right kind of carbohydrates. The right type of carbohydrates will fill you up, and you will maintain that feeling of satiety (feeling full) longer. The right types of carbohydrates will help you burn more body fat and less of the stored carbohydrates that are needed for reserves.

We divide carbohydrates into two types: those with a high-glycemic index (over 50) and those with a lower-glycemic index. High-glycemic index carbohydrates cause an immediate rise in blood sugar, peaking quickly then falling, leaving you hungry faster. Examples of these are breads, potatoes, sugar, and candy. Low-glycemic index carbohydrates cause a much slower rise in blood sugar and give you the sensation of feeling full for hours after eating them. Examples include many fruits, lentils, beans, and most vegetables.

Take a typical “continental” breakfast choice: most restaurants have a wonderful selection of donuts and fruit. An apple contains about 25 grams of carbohydrates, and a donut also contains 25 grams—so, which is better? Okay, the apple is better, but why? If one just counts carbohydrates then 25 grams is 25 grams.

Weight loss surgery patients understand carbohydrates using the Glycemic Index

The answer is the glycemic index. A donut has a glycemic index around 75, which is fairly high. When you eat the donut, your body will be able to digest it quickly, causing a rapid rise in blood sugar, and then the blood sugar will drop rapidly. The result is that you will feel great for a bit, then hungry, as the donut has digested, and a bit shaky as the blood sugar has dropped. An apple has a glycemic index of 34, which is fairly low. Eating the apple will cause a slow rise in blood sugar; it takes your body a while to digest it. You won’t get the quick rise, or quick fall and you will feel full longer. But even more, the apple contains more vitamins, better nutrition, and more fiber than the donut.

Glycemic Index

High-glycemic foods tend to lead to obesity, diabetes, heart disease, and even cancer. Does that mean you must never have that donut, the white bread, or the lasagna? Not at all. The good news is that if you combine a low-glycemic food with a high-glycemic food, you average the glycemic index number. But it is even more practical than that. At one time if you were diagnosed with diabetes you were told you could never have sugar again. The new thinking is that we can combine foods to decrease the glycemic index as much as possible.

How can you tell the high-glycemic foods from the low-glycemic ones? There is no simple answer here; this is all done by testing. People eat the food and we measure the blood sugar levels.

Processed foods are almost universally high-glycemic index carbohydrates. White bread, for example, is a highly processed form of grain that causes rapid rises in blood sugar and leaves you feeling hungry. The more foods have been processed, the more likely they are to lead to obesity.

Think of processing as pre-digesting. Companies process flour, oats, and other items by removing the fibrous coating on grains. This makes them easier for your body to absorb; your digestive system doesn’t have to do any work. The mills are doing the work that your digestive system should do.

What choices did successful weight loss surgery patients make?

Sometimes talking about certain foods to patients who have reached their goal weight is like talking to an alcoholic about vodka. Some patients who have reached their goal all had a simple, single, vision of where they wanted to go, identified those foods that got them in trouble, and avoided them zealously. Most who reach goal avoided highly-processed, high-glycemic index carbohydrates—potatoes, bread, rice, and pasta. They also avoided fast food places, and alcohol. Once they were within sight of their goal they would expand their diet, being wary of certain foods and watching the scale. The scale doesn’t lie. If you have expanded your diet and notice that the scale creeps upward, then something you have added is not working for you. Again—measuring allows you to manage your choices.

There are two approaches to carbohydrates, one is to simply count carbohydrates and not exceed a certain number. This is an over simplistic approach that ignores the simple fact that certain carbohydrates are quite good for you. For example, there is nothing wrong with an apple (25 grams of carbohydrates)—but the donut (which also has 25 grams of carbohydrates) has a lot of disadvantages.

For carbohydrate counters, the total daily amount of high-glycemic index carbohydrates (glycemic index over 50) should not exceed 60 grams. If you go over this amount you will risk regaining weight. Remember, sugars are not your friend. The more sugar you eat, the longer it will take to lose weight. Sugar is in many things that you might not even consider: fruit juices, processed food products, condiments such as ketchup, and also in canned fruits, pastry products, pasta, and breads. Sugar is very well absorbed after any bariatric surgery, which means the more foods you eat with sugars, the longer it will take to lose weight.