The South Beach Diet (2 page)

Refined carbohydrates, on the other hand, are found in packaged, processed foods, such as store-bought baked goods, crackers, pasta, and white bread.

Refined carbohydrates are made with white flour and contain little or no fiber. In fact, many products made with white flour are advertised as fortified with vitamins and minerals, because the process of turning grain into white flour strips away its fiber and nutrients. One of our South Beach Diet rules is to avoid foods labeled as “fortified.” Current evidence is that fortification with vitamins does not recreate the benefits of the natural vitamins that have been removed.

Despite the fact that good carbs are a critical part of a healthy diet, the typical American diet is filled with the bad kinds. And when we’re overweight as a result of a diet laden with bad carbs, our bodies’ ability to process
all
carbohydrates goes awry. To understand why, you need to understand the role of the hormone insulin.

Insulin, Fat, and “Fast Sugar”

All foods, even natural foods like fruits and beans, contain naturally occurring sugar in some form. But there’s a critical difference among these sugars: The body digests and absorbs them at different speeds.

When sugars from food enter the bloodstream, the pancreas produces insulin. It’s insulin’s job to move sugars out of the blood and into the cells, where they’re either used or stored for future use. Insulin is the key that “unlocks” our cells and lets sugars in.

How much insulin is required to do that job depends on the foods we eat. Foods that are broken down and absorbed into the bloodstream quickly require a lot of insulin. Those that are metabolized and enter the blood more slowly require a gradual release of insulin.

In a nutshell, the quicker sugar floods the bloodstream, the quicker insulin rises. This is bad, both for your weight and for your general health.

Here’s why: When glucose is absorbed slowly, the rise in blood sugar is gradual—and so is its fall, once insulin begins to work. A slow decline in blood sugar means fewer cravings later.

But when blood sugar rises quickly, the pancreas pumps out a correspondingly high level of insulin. The result? Blood sugar drops so low that it triggers new cravings. Often, we satisfy cravings by overeating (typically bad carbs like chips and candy bars), which leads to weight gain. Worse, the excess weight caused by overeating can lead to insulin resistance, the precursor to full-blown type 2 diabetes. In insulin resistance, cells ignore insulin’s signal to accept glucose from the blood. As a result, the pancreas must crank out huge amounts of insulin until eventually the exhausted organ wears out.

Those of us who have grown protruding bellies while our arms and legs stay relatively thin are likely to have the syndrome of insulin resistance or “pre-diabetes.” This occurs commonly in people with a family history of diabetes. Another sign of this syndrome is the occurrence of fatigue, weakness, headaches, irritability, shakiness, and cravings in the late morning or late afternoon. These are signs of exaggerated falls in blood sugar levels. The consumption of refined carbohydrates has unmasked this syndrome in approximately 25 percent of Americans and in the great majority of those of us who are overweight.

While eating the South Beach way will result in weight loss, it will also correct the way your body reacts to the very foods that made you heavy. It increases your body’s sensitivity to insulin, thereby decreasing the swings in blood sugar that cause us to be hungry again, too soon after we finish a meal.

This metabolic transformation occurs in three phases. The purpose of Phase 1 is to eradicate your cravings. You will accomplish this by eliminating all starches including all breads, potatoes, and rice. You will also eliminate all sugars, including all fruits and alcoholic beverages. You will enjoy strategic snacking, eating healthy snacks like nuts or low-fat cheese before your blood sugar dips too low in the late morning afternoon and/or evening. It takes much fewer calories to prevent those afternoon cravings than it does to satisfy those cravings once they hit. In Phase 1, nutrient rich vegetables and healthy salads are encouraged. You can expect to lose between 7 and 13 pounds during Phase 1.

In Phase 2, you’ll gradually add back good carbohydrates, such as whole fruits and whole grains. Here’s the principle for adding more carbs back safely: Do it gradually and attentively. The goal is to eat more carbs again while continuing to lose weight. If you add an apple and a slice of bread a day and you’re still dropping pounds, that’s great. If you try having an apple, two slices of bread, and a banana daily and notice that your weight loss has stalled, you’ve gone too far. It’s time to cut back, or try some different carbs and monitor the results. You can enjoy a glass of red or white wine with a meal; drinking wine with a meal actually helps slow digestion. In this phase, weight loss is about 1 to 2 pounds per week. You learn which carbs you can enjoy without the return of cravings.

Once you have reached your weight loss goal, it is time for Phase 3, the maintenance phase. There are no absolute restrictions here, but you have learned the “pecking order” of the important food groups. You have learned to choose brown rice instead of white rice, sweet potatoes instead of white potatoes, and pita bread rather than white bread. This is where the South Beach Diet becomes a lifestyle. (For an idea of which foods to avoid and which foods to enjoy on the South Beach Diet, see the lists on the next pages.)

In the next section, you’ll be introduced to a system that can help you limit foods that cause unhealthy, fat-producing spikes and dips in blood sugar and insulin and choose those that keep blood sugar steady, making it easier to lose weight and keep it off.

Introducing the Glycemic Index

The glycemic index (GI) is a system that ranks foods by how fast and how high they cause blood sugar to rise after eating a particular food. The GI of any particular food is always compared to a standard reference food, which is either one slice of white bread or a small amount of glucose, both of which have a numerical value of 100. The higher the glycemic index, the greater the swings in blood sugar produced. So, in general, the lower the glycemic index, the better the food choice. For mixed meals, the total glycemic index is approximately the average of the indices of the individual foods.

Generally speaking, you can think of GI in 3 ranges: “low” (55 and below), “medium” (56 to 69), and “high” (70 or above).

Foods with a low GI are converted to glucose more slowly, and so their sugars enter the bloodstream more slowly. Foods with a medium or high GI, which are converted to glucose more quickly, release their sugars into the bloodstream more rapidly. This results in a swifter rise in insulin.

Unrefined carbs often fall lower on the GI scale because they’re rich in fiber, which takes longer to digest and so results in a slow, gradual rise in blood sugar.

How about refined, bad carbs? Not surprisingly, their processed sugars enter the bloodstream quickly. This quick conversion makes blood sugar and insulin rise and fall quickly—definitely not so good.

On the South Beach Diet, you’ll tend to eat foods that fall lower on the GI, prepared or eaten in ways that allow your body to digest and absorb them more slowly. After Phase 1, the strictest phase of the Diet, you’ll reintroduce good carbohydrates with a higher GI.

While the GI is an astounding breakthrough in our understanding of how carbohydrates affect our metabolism, there are a few important things you need to know to use the system successfully. First, the GI doesn’t account for portion size. The solution: the concept of the glycemic load (GL), which takes into account a food’s GI (the quality of carbohydrate) as well as the amount (the quantity of carbohydrate) per serving. It also represents the load, or stress, placed on the pancreas from the amount of carbohydrates consumed from a particular food or meal.

For this Guide, our evaluation of each food choice is based on the glycemic index, glycemic load, and on other factors as well. We don’t include a dedicated column with a GI number for each entry because that information is not available for all of the 1,200 foods that are listed in these pages.