Carbohydrates are broken down by various enzymes into simple sugars then glucose so they can be absorbed into the blood. Digestive enzymes are like biological scissors – they chop long starch molecules into simpler ones.
If we cannot burn all the fat we consume, the remainder is stored as fat tissue. This fat-burning ability is determined by the amount of insulin in our bloodstream. When insulin levels are low, we burn mainly fat. When they are high, we burn mainly carbs. But a problem arises when insulin levels remain constantly high, as in the case of individuals suffering from insulin insensitivity. In such cases, the constant need to burn carbohydrates reduces our fat-burning ability. Result? More fat is stored as fatty (adipose) tissue.
The speed of digestion is determined by the chemical nature of the carbohydrate itself, and thus how “resistant” it is to the activity of the enzymes. A simple sugar is usually much less resistant than a starch, and is digested or metabolized much faster. Things that slow down digestion include: the presence of acid (from gastric juices or the food itself), and the presence of soluble fiber.
High Insulin Levels May Increase Risk of Obesity
This is why experts are linking high insulin levels, together with a reduced ability to burn fat, with obesity. And as you can see, high insulin levels are typically determined by the type of carbohydrates we eat. High GI foods or meals trigger higher levels of insulin than intermediate or low GI foods. This is why the Glycemic Index is considered to be so important when assessing our eating habits.
As we have seen, the human body is fuelled by glucose. Therefore all foods must be converted into glucose before they can be used as fuel. Carbohydrates are more easily converted into glucose than protein or fat, and are considered to be the body’s “preferred” source of energy, and the brain’s essential source of energy.
Simple carbohydrates (excepting fruit sugar) are more easily converted into glucose because their molecular structure breaks down faster in the stomach and small intestine. Therefore they raise glucose levels in the bloodstream quite rapidly (less than 30 minutes). This explains why diabetics, who occasionally suffer from an excessively low blood-glucose level, can quickly restore their balance by eating simple carb-foods, like sweets.
Potential Diet Killer! Food High In Carbohydrates
When it comes to maximizing your energy levels, carbohydrates are the best “go” food around. Think of them as gas in your fuel tank. If you don’t provide yourself with enough throughout the day, you simply won’t have the energy to function. Now this would be a shame for new moms who definitely don’t have much of an energy reserve and who have one or more little kids relying on them for just about everything.
Everything we eat is made up of some combination of protein, fat, and carbohydrate. Simple sugars, like table sugar, starches, like pasta, and fibre, like oat bran, are types of dietary carbohydrates. All carbohydrates deliver four calories per gram. Something to digest: All carbs are not bad! they are vital because they provide the body with the energy it needs to support daily activities-from breathing and digestion to thinking and exercise. Consuming whole grain and high fibre carbohydrates, including fruits, veggies, dried beans, and whole grain cereals, breads and crackers will make you feel satisfied for longer periods of time than foods high in refined sugar and low in fibre (i.e. cakes, cookies, sugary candy, etc.). Foods high in fibre expand in your digestive tract making you feel full. To visualize how fibre can expand, put a piece of whole grain or bran cereal in a bowl with a little water then watch it swell to two to three times its original size. This makes it very clear how fibre can help make us feel fuller.
In general, carbohydrates cause blood sugar levels to rise quickly while fat and protein cause blood sugar to rise more slowly. In response to a rise in blood sugar, the body releases insulin, the hormone required to bring blood sugar into cells or fat tissue. If one eats excessive amounts of carbohydrate, the insulin cycle can become imbalanced, resulting in continually raised insulin levels. High insulin levels have been associated with obesity as well as increased risk for heart disease and blood sugar imbalances. Controlled carbohydrates diets may promote a gradual rise and fall of insulin and are therefore more satiating. In high protein/controlled carbohydrates diets, it is thought that weight loss occurs through consumption of fewer calories resulting from increased satiety. Weight loss also occurs because very low carbohydrates intake triggers a condition called ketosis, which forces the body to burn fat stores, but ketosis can be unhealthy if continued for a long period of time.
The glycemic index measures how quickly a carbohydrate digests, enters the bloodstream, and raises blood sugar levels. High glycemic index foods, such as refined flours and high sugar beverages, are quickly digested, causing a rapid rise in blood sugar and insulin levels. Such effects have been linked to diabetes, overeating, and obesity. Low glycemic index foods, in general, foods high in fibre and protein, contribute to a steadier blood sugar level and have been shown to lower cholesterol levels and decrease the risk of diabetes. Many diets recommend eating low glycemic index foods, such as beans, dairy products, fruits, and vegetables. Keep in mind that the glycemic index of a food may be balanced in the context of a meal where several foods of varying glycemic levels are consumed.
Remember, many theories exist about what constitutes a “perfect” diet. We believe a good foundation for any diet consists of a mix of fresh, minimally processed foods from all food groups, including: lean proteins; fresh fruits and vegetables; whole grain-based breads, cereals, and pastas; and heart-healthy fats such as olive oil, nuts, and avocado. And, just as important, a good diet contains delicious foods you enjoy and is one that you can maintain as an ongoing lifestyle choice.