Diet details

A low-carb diet limits the amount of carbohydrates you eat.

Carbs include three types:

• Sugars, also called simple carbs, such as table sugar.
• Starches, also called complex carbs, such as brown rice.
• Fiber, the parts of foods that are harder for the body to digest, such as apple skins, beans and whole-grain bread.

The body uses carbs as its main energy source. As the body digests food and beverages, it breaks down complex carbs, such as whole grains or white flour, into simple sugars, also called carbs. In general, you digest complex carbs more slowly. Glucose is a type of simple sugar released into the blood as you digest food.

Common sources of healthy carbohydrates include:

• Vegetables, such as Brussels sprouts or cucumbers.
• Whole grains, such as whole-wheat bread, brown rice, oats and quinoa.
• Fruits, such as apples or oranges.
• Legumes, such as black beans, lentils and chickpeas.

Complex carbohydrates are further divided into refined grains, such as white flour, and whole grains, such as whole-wheat flour. Whole grains are healthier than refined grains and simple carbohydrates because they:

• Have more fiber.
• Have more vitamins and other nutrients.
• Have beneficial health effects on blood pressure and blood glucose, as well as cancer, heart disease and other conditions.

Refined grains, such as white flour, often are added to processed foods. Milling and grinding grains such as wheat processes or refines them. This takes out fiber and nutrients. It makes the grains stay fresh longer, but it makes them less healthy for you. Examples of food made with refined grains are white bread and pasta.

In the body, the pancreas releases the hormone insulin, which helps glucose enter the body's cells, like a key unlocks a door. The cells can use glucose for energy only after insulin helps the cells absorb it. The body stores extra glucose in the liver and in muscles. The body also can store extra glucose as body fat.

A low-carb diet is meant to cause the body to burn stored fat for energy, which leads to weight loss.