Beans, green vegetables, seeds, and some fruits are high in soluble fiber. Soluble fiber supplies a gelatinous-like material in the bowel. It is not absorbed and does not give us calories. Soluble fiber is very important, as it slows the absorption of glucose and helps lower cholesterol. Beans are especially high in soluble fiber.
Insoluble fiber—roughage—is important too. It provides bulk to our stool and keeps us regular. And guess what: seeds, nuts, vegetables, and, yes, beans have plenty of insoluble fiber too.
For years, nutritionists and scientists thought there were only two kinds of fiber—soluble and insoluble. Now we know there is a carbohydrate that acts like a fiber too. It is called resistant starch. It supplies few calories, and most of the calories do not raise glucose levels. It is called resistant starch because it is resistant to stomach acid and digestive enzymes. It is not digested in the small intestine but passes to the large intestine, where it undergoes fermentation. Fermentation means that the bacteria decompose and degrade this starch into simpler compounds. When the bacteria in the bowel degrade the resistant starch, it forms new compounds that have health benefits. Resistant starch is important for good health and has beneficial effects for diabetics.
Legumes such as beans, lentils, peas, and chickpeas fall far below grains on the list of foods Americans eat. However, legumes are richer in nutrients, protein, and fiber, and they contain much higher levels of resistant starch. Considering their favorable effects on blood sugar and weight loss, they are the preferred carbohydrate source for people who have diabetes or are at risk for diabetes.
Most starchy foods have a small amount of resistant starch in them. At the beginning of human history, fruits contained more resistant starch and fiber and less sugar than fruits that are commonly available now. Wild foods, the same as those early human foods, are more fibrous compared to what is bred, cultivated, and processed today. If you were to taste a wild pineapple, wild lychee, or wild plantain in the tropical jungle, you would find that any of them are hardly sweet, much chewier, and fibrous—and filling from all the fiber—but they are certainly not calorically dense. It is certain that in a primitive tropical habitat that provided a diet of just wild food and greens and maybe some fish, there would be no overweight or diabetic people. If you were ever shipwrecked on a deserted island, it would be almost impossible to become or remain overweight.
Proponents of high-protein, low-carbohydrate diets argue that intake of carbohydrates—especially starch—should be restricted or eliminated and substituted with animal products instead. This might seem logical on a superficial level, but when you look deeper into the science, you find that fiber-less animal products contribute to diabetes-related health risks, while beans—even though they are largely carbohydrates— directly lessen these risks and promote the reversal of diabetes.
Dietary starch is most often converted to glucose. When not burned as energy for immediate use, it is stored as glycogen, a high molecular- weight polymer of glucose. The body is capable of storing approximately 300 to 500 grams of glycogen at one time. Any excess glucose that is not rapidly burned as fuel or stored as glycogen is converted to fat and stored as body fat. Meat-based-diet proponents argue that to lose weight, we should eat less starch. They are right to a degree. Certainly we should eat less high-glycemic, low-nutrient starch, and certainly we should not overeat. When we eat mostly high-starch foods, especially refined carbohydrates, it promotes swings in blood glucose, putting excess work on the pancreas to produce a huge insulin load. Plus if we overeat, our glycogen stores could be already full, meaning the extra carbohydrate calories we don’t need will be stored as fat on the body. But not all carbohydrates fall into this high-glycemic, low-nutrient starch category.
The Whiter the Bread, the Sooner You’re Dead
Some people think that sugar-free cookies, cakes, and pastries can actually help their diabetes or help them lose weight. This is not the case—these sugar-free products are essentially low-nutrient junk foods. White flour actually makes your blood sugar rise almost as much as plain sugar does.
Carbohydrates are chains of sugar molecules lined in a row. They are found in all plants and foods made from plants. Carbohydrates can be a single sugar, or three or four bound together, but when thousands of sugars are bound together, they are called starch. When these simple carbon molecules are bound together so tightly that your body cannot break them down and digest them, they are called fiber.
Only simple sugars can pass from your intestines into your bloodstream. When your digestive enzymes break down the carbohydrates into simple glucose molecules, they are absorbed immediately and enter the body just as if you had sucked on a sugar cube. Indeed, eating sugar and white flour does not cause just diabetes; these foods are also linked to heightened risk of cancer. Quite a few studies have linked the consumption of high-glycemic, low-nutrient food to cancer. One study showed over a 200 percent increase in risk of breast cancer in women eating more than half their diets as refined carbohydrates. Too many Americans still eat this type of diet, with more than half their calories coming from processed foods. These individuals are slowly destroying their health. Eating processed foods is like snorting cocaine. Eventually you will pay a big price—your health. And the more a person consumes this deadly white stuff, the stronger the cravings for more.
Bagels, white bread, pasta, pizza, and rolls are all staples of the American diet, and they are a large contributor to our epidemic of obesity, diabetes, heart disease, and cancer. Commercial wheat products are also treated with fungicide, sprayed with insecticides, and bleached with chlorine gas or other chemicals. They return little nutrient bang for all their calories. To put it bluntly, these staples of our diets are disease-promoting junk food. All the white starches—basically, white bread, white rice, and even white potatoes—are very rapidly converted to glucose, which is sugar, and absorbed into the bloodstream, shooting blood sugar levels up.
When blood sugar skyrockets, it overworks the pancreas to match the load of sugar with a large amount of insulin. This is not only stressful to the body and the pancreas, but metabolizing that large energy load without a concomitant intake of micronutrients creates metabolic havoc in the cells. Toxic metabolites build up in cells when we consume calories without antioxidant and phytochemical micronutrients needed to remove and control the toxic by-products. So as we eat more low-nutrient and low-fiber carbohydrates, we build up more cell toxicity, leading to disease and food addiction.
Most of the common carbohydrates we eat are turned into glucose, but it is important to realize that the conversion efficiency and rate vary greatly from one type of carbohydrate to another. For example, the starch in potatoes, cereals, and baked goods digests very rapidly; all their calories are converted quickly, supplying the body with a huge glucose load. The starch in beans, barley, and black wild rice is digested more slowly and causes a much slower and lower blood sugar rise. Beans are at the top of the preferred carbohydrate totem pole because they contain more of both slowly digestible starch and resistant starch.
Unique properties of the carbohydrates in beans and legumes include:
- Higher amount of slowly digestible starch
- Higher amount of resistant starch
- Higher amount of insoluble fiber
- Higher amount of soluble fiber
Resistant starch actually goes all the way through the small intestine without being digested at all. In this way, it is more like fiber, and in some cases is classified as a type of insoluble fiber.