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Carbohydrate 101

What is a carbohydrate?

Carbohydrates are one of three macronutrients: carbohydrates, protein, and fat. They contain carbon, hydrogen, and oxygen atoms. Carbohydrates provide most of the energy needed in our daily lives for normal body functions such as heartbeat, breathing, and digestion and for physical activity and exercise.

Net carbs are the total amount of carbohydrates in a food item that impacts blood sugar levels. It is calculated by subtracting the dietary fiber and sugar alcohols, if any, from the total carbohydrates present in the food.

What are net carbohydrates?

Dietary fiber and sugar alcohols are subtracted from the total carbohydrates because they are not fully digested or absorbed by the body. Fiber passes through the digestive system largely intact and does not significantly raise blood sugar levels. Sugar alcohols are partially absorbed and have a smaller impact on blood sugar than regular sugar.

Which foods contain carbohydrates?

• Grains and grain products

• Fruits

• Vegetables

• Beans and legumes

• Dairy products

• Sugars

Do I need carbs?

High-carbohydrate foods are the best and sometimes only food sources of many essential nutrients, including:

• Fiber

• Vitamins C & E

• The majority of B vitamins

• Carotenoids and other beneficial phytochemicals

• Potassium

• The majority of trace minerals

A diet that is low in or deficient in any of these nutrients leads to many health problems, including an increased risk for osteoporosis, high blood pressure, and heart disease.

Are high-carbohydrate diets fattening?

One gram of carbohydrate contains 4 calories. Not necessarily. Obesity is uncommon in Asia, where most people eat a high-carbohydrate diet. But not all high-carbohydrate foods are created equal. Some, such as whole grains, potatoes, fruits, and vegetables, help you eat fewer calories without hunger.

What should I eat if I want to lose weight?

You should eat more fruits and vegetables, especially nonstarchy vegetables like lettuce, broccoli, tomatoes, and spinach. You should also try to eat grains in a more whole, unprocessed state like those in the “skinny” carb list. Get 2-3 servings of nonfat milk or yogurt for calcium. Choose high-protein foods good for your heart, like beans, nuts, fish, and white poultry without the skin. If you eat meat, choose lean cuts and limit portions to 3 ounces or less. Cook and eat with minimal fat.

Not All Carbs Are Created Equal

Refined carbohydrates are carbohydrates that have undergone processing, during which the natural fibers, vitamins, and minerals present in the original food source are removed or significantly reduced. This processing typically involves removing the bran and germ portions of grains, leaving behind the starchy endosperm.

Common examples of refined carbohydrates include white bread, white rice, pasta made from refined flour, pastries, cakes, cookies, sugary cereals, and most processed snack foods. These foods are often highly processed and have a smooth texture and longer shelf life compared to whole grain alternatives.

The refining process strips away the fiber, which slows down digestion and helps regulate blood sugar levels, as well as many nutrients. As a result, refined carbohydrates are quickly digested and absorbed by the body, causing a rapid increase in blood sugar levels. This can lead to spikes and crashes in energy levels, increased hunger, and can contribute to weight gain, insulin resistance, and other health issues if consumed excessively.

Refined carbohydrates are often associated with a higher glycemic index (GI), which is a measure of how quickly a food raises blood sugar levels. Foods with a high GI value cause a more rapid increase in blood sugar compared to foods with a low GI value.

In contrast, unrefined or whole carbohydrates, such as whole grains, fruits, vegetables, and legumes, retain their natural fiber and nutrients, resulting in slower digestion and a more gradual release of glucose into the bloodstream. These whole carbohydrates are generally considered healthier choices because they provide more sustained energy, better nutrient profiles, and are associated with various health benefits.

It's important to note that not all carbohydrates are unhealthy, and a well-balanced diet should include a variety of nutrient-dense carbohydrates, such as whole grains, fruits, and vegetables, while limiting the consumption of refined carbohydrates and added sugars.

Take a look at our lists below. The numbers on the right measure the density of calories in a food by showing how much each food contains per pound. Non-starchy vegetables, such as lettuce, tomatoes, and carrots, are the lowest in calories while foods that contain white flour, sugar and fat, such as cookies, are the highest.

“Skinny” Carbohydrates and their calorie content per pound:

  • Vegetables, non-starchy 195

  • Fruits 135-425

  • Skim milk 158

  • Hot cereals 242-281

  • Brown rice 488

  • Potatoes, yams 494

  • Barley 557

  • Whole-wheat spaghetti 562

  • Beans 576

Calorie-Dense Carbohydrate Foods and their calorie content per pound:

These include foods high in sugar, refined grains, and/or fat.

  • Ice cream 1,283

  • French fries 1,400

  • Cake with frosting 1,544

  • Pretzels 1,700

  • Sweetened dry cereal 1,701

  • Cheesecake 1,733

  • Baked potato chips 1,760

  • Doughnut 1,800

  • Croissant 1,800

  • Brownies 2,000

  • Snickers 2,163

  • Cookies 2,200

  • Crackers 2,268

  • Potato chips 2,450