Carbohydrates are often cast as the evil villain in our diets, blamed for obesity, diabetes, and all manner of disease. The truth is, your body needs a certain amount of carbohydrates to function.
In this installment of Simple Food Terms Explained, we re-visit carbohydrates in hopes of understanding the role of carbohydrates, the different types of carbohydrates and how they work in your body can lead to a healthier, well-balanced diet and higher performance.
Carbohydrates are the main source of energy for your body. There are three main types:
Sugar: The smallest form of carbohydrates that our bodies use, sugars contain 4 calories for each gram. Sugars are naturally occurring in fruits and milk. When you take sugars in through these forms, you also get other nutrients including vitamins and minerals. Sugars that are added to foods either at home or during processing are mostly empty calories and do not add nutritional value to our foods even though they may make the food taste better. Sugars we add at home can be honey, white table sugar, brown sugar, and syrups. Sugars added during processing are listed on food labels as fructose, sucrose, dextrose, and lactose.
Starch: Called a complex carbohydrate, starches are made up of small chains of sugars which are broken down to form energy. Starches do not have the sweet taste of sugars but can still raise the blood sugar level as each sugar molecule that makes up the starch still contains calories. Starches take longer to digest than sugars. Starchy foods include legumes and grains but also vegetables like corn, peas, squash and sweet potatoes which provide other important vitamins and fiber.
Fiber: Another form of carbohydrate, fiber is also called roughage or bulk. Fiber works in your body to keep your digestive tract functioning. Foods that contain fiber often have other carbohydrates as in fruits, vegetables, whole-grain cereals, and legumes. Processed foods often have the fiber removed and only the sugars and starches remain which means the healthiest carbohydrates are removed.
Why You Need Carbohydrates
Dietary guidelines recommend that carbohydrates make up 45 to 65 percent of your daily diet. As the main source of fuel for your body, carbohydrates are broken down and absorbed into your bloodstream as glucose. Glucose is important in cell function and fuels every activity your body does from moving to breathing. Extra glucose is stored in organs including the liver, muscles, and fat.
The right kind of carbohydrates, especially from whole grains and fiber, are known to help improve health and even prevent disease. When your diet is high in sugars and starches without fiber, serious consequences can develop which include obesity, diabetes, and some evidence shows that excess sugars may contribute to the growth of cancers and other diseases.
Carbohydrates and the Glycemic Index
The Glycemic Index (GI) is a measure of how quickly carbohydrates are released into the bloodstream after consumption. Foods high on the glycemic index release glucose rapidly into the bloodstream and foods low on the index release glucose slowly. Foods low on the GI scale may help foster weight loss and as part of an everyday diet are the best foods for you to focus.
If you are a long-distance runner, you may want to take in a few foods that are high on the GI scale as part of recovery and quick energy intake. Scored on a scale of 1 to 100, foods made up of mostly of sugar such as soda have a higher GI score than foods that are high in fiber such as lentils or soybeans.
Along with knowing how quickly the glucose enters the bloodstream (GI), it is also important to know how much glucose that food will deliver. This is called the glycemic load. Foods that might be high on the glycemic index, may also have a low glycemic load. For example, watermelon has a high GI score, but because of the fiber content, has a low glycemic load.
Carbohydrates and Cholesterol
Most people believe that carbohydrates and cholesterol are completely unrelated, but actually, the opposite is true. The relationship between these two dietary terms is important. Low-fat foods sometimes have a higher carbohydrate content to improve taste or texture and if your focus is lowering your cholesterol, you must watch the carbohydrate intake as well.
Carbohydrates or sugars enter the bloodstream as glucose. As glucose levels rise, the pancreas releases insulin to break down the glucose into either glycogen which is stored and used by cells for energy or triglyceride. When the body store of glycogen is exceeded, the breakdown into triglyceride begins. Triglyceride is transported and stored in fat cells and can be released for energy between meals. If you are eating more calories than your body needs, especially in the form of carbohydrates, you can start to build up triglycerides and increase the other fats in your bloodstream.
Our bodies are complex machines that need different nutrients to function properly. A balanced contains a proper mix of these nutrients including carbohydrates. Knowing which carbohydrates are best, checking food labels and eating whole grains, fruits, and vegetables while avoiding processed foods can help you make sure your carbohydrate intake is good for your body.