Diet details

A low-carb diet restricts the amount of carbohydrates you eat. Carbohydrates are grouped as simple natural (lactose in milk and fructose in fruit), simple refined (table sugar), complex natural (whole grains or beans) and complex refined (white flour).

Common sources of naturally occurring carbohydrates include:

• Grains
• Fruits
• Vegetables
• Milk
• Nuts
• Seeds
• Legumes (beans, lentils, peas)

In general, complex carbohydrates are digested more slowly and they have less effect on blood sugar than refined carbohydrates do. They also provide fiber.

Refined carbohydrates such as sugar or white flour are often added to processed foods. Examples of foods with refined carbohydrates are white breads and pasta, cookies, cake, candy, and sugar-sweetened sodas and drinks.

Your body uses carbohydrates as its main energy source. During digestion complex carbs are broken down into simple sugars (glucose) and release into your blood (blood glucose).

Insulin is released to help glucose enter the body's cells, where it can be used for energy. Extra glucose is stored in the liver and muscles, and some is converted to body fat.

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

Typical foods for a low-carb diet

In general, a low-carb diet focuses on proteins and some nonstarchy vegetables. A low-carb diet generally limits grains, legumes, fruits, breads, sweets, pastas and starchy vegetables, and sometimes nuts and seeds. However, some low-carb diet plans allow small amounts of fruits, vegetables and whole grains.

A daily limit of 0.7 to 2 ounces (20 to 57 grams) of carbohydrates is typical with a low-carb diet. These amounts of carbohydrates provide 80 to 240 calories. Some low-carb diets greatly restrict carbs during the initial phase of the diet and then gradually increase the number of allowed carbs.

In contrast, the Dietary Guidelines for Americans recommends that carbohydrates make up 45% to 65% of your total daily calorie intake. So if you consume 2,000 calories a day, carbs would account for between 900 and 1,300 calories a day.