The Program: How Does the Atkins Diet Work?

Why Adequate Protein Is Essential to Weight Management

Protein foods are crucial to your health and low-carb lifestyle. Eating sufficient protein in partnership with enough natural fat allows you cut down on carbs and helps protect lean tissue mass while promoting fat loss.

Protein Works Overtime

Protein is a component of every cell and organ in your body and provides the building blocks necessary to construct and repair cells. Proteins are made from 20 different amino acids that are linked together like a strand of pearls. When you digest protein foods, the links break apart so the amino acids can be absorbed into your bloodstream. Without a continuous supply of amino acids, your existing cells shrink and new cells cannot be produced. When you embark on a weight loss diet, you want to shrink the cells that store body fat, but not muscle and other critical cells. Eating protein also increases blood levels of amino acids, contributing to:
  • Increased satiety (a sense of fullness)
  • More stable blood sugar levels
  • Burning of more calories

Protein Fills You Up

A number of studies have shown that consuming protein is more satiating than consuming either carbohydrate or fat. This may be one reason why diets with more than the minimum amount of protein have been shown to result in better weight loss. When you replace some carbohydrate with protein in your diet, you experience fewer fluctuations in blood sugar. Plus, you actually burn more calories when digesting protein than when digesting fat or carbohydrates, giving protein an advantage. Higher-protein diets have been linked to prevention of obesity and muscle loss, as well as a reduced risk of developing metabolic syndrome, type 2 diabetes and heart disease.

Protein Protects Lean Body Mass

Research also shows that higher-protein diets are associated with greater retention of lean body mass during weight loss—independent of calorie intake—with beneficial effects on body composition. When slimming down, you want to lose only fat. But with most diets, about one-quarter of the total lost pounds normally come from lean body mass. The key to maintaining lean mass is to keep your protein synthesis greater than or equal to your protein breakdown. Not surprisingly, up to a point, eating protein foods boosts protein synthesis, while inadequate protein intake may result in lost lean body mass. This is one reason that we recommend consuming some protein at every meal, including breakfast.

How Much Protein?

The government’s recommended dietary allowance (RDA) for protein is 0.36 gram per pound of body weight for adults a day. For a 150-pound person, that’s about as much as you’d consume in a large chicken breast and a handful of nuts. It’s important to understand that the RDA reflects the minimum, not the optimal, amount of protein an average healthy person needs. Many factors increase your minimum protein needs, such as your age, gender, body composition (ratio of fat to lean body mass) and whether you’re still growing, are pregnant, have inflammation or are dieting. Even the amount of stress you may be under can be a factor. Research indicates that adults benefit from protein intakes above the RDA, particularly when they’re losing weight.

Depending upon your gender and your height, we recommend that you consume between 4 and 6 ounces of protein at each meal, including breakfast. Smaller women can stay at the lower end of this range and very tall men may need to eat as much as 8 ounces at each meal. Spread your intake out over the day. The following visual comparisons should help you estimate amounts without needing to weight foods:

Food Visual
1 ounce meat, poultry, tofu, etc. Small matchbox/remote car key
3 ounces meat, poultry, tofu, etc. Deck of cards/cell phone
8 ounces meat, poultry, tofu, etc. Slim paperback book
3 ounces fish Check book/iPod
1 ounce hard cheese   Four dice

Unless your initial portions are larger, there’s usually no need to reduce your protein consumption as you move through the phases. But you may want to decrease your protein portions if you’re at the higher end of the range to see if that may be the holdup. One way to judge if you’re getting enough protein is simple: take the satiety test. After you’ve consumed what you consider an adequate amount of protein (which naturally comes with a modest dose of natural fat), ask yourself if you’re satisfied. If you are, fine. If not, have a bit more. If you’re still hungry, try adding some olive oil, cream, or salad dressings or sauces. You need pay closer attention to your protein intake only if you think you might be eating too little or too much.

For more on the role of protein in the Atkins Diet, see Protein: The More Variety the Better and Atkins Is Not a High-Protein Diet.
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Disclaimer: Nothing contained on this Site is intended to provide health care advice. Should you have any health care-related questions, please call or see your physician or other health care provider. Consult your physician or health care provider before beginning the Atkins Diet as you would any other weight loss or weight maintenance program. The weight loss phases of the Atkins Diet should not be used by persons on dialysis or by pregnant or nursing women.