The South Beach Diet is similar to the Atkins Diet in that it has an initial two week phase I period that drastically reduces carbs. The difference between Atkins and South Beach is that there are good carbs and bad carbs. The glycemic index of a food is what counts. The glycemic index is how much a food increases blood sugar compared to the amount that same quantity of white bread would increase blood sugar.

A spike in the blood sugar or glucose, signals the pancreas to make more insulin. The insulin’s job is to get the sugar out of the blood stream into the organs for energy or into storage. The body stores glucose as fat. Keeping the blood sugar from spiking means less insulin is produced which means the sugars are absorbed slowly resulting in a steady level of decreasing sugar levels rather than a rush. Low blood sugar leads to cravings for sugary foods and over eating. And the cycle starts again.

Bad carbs spike the blood sugar. Good carbs don’t. Good carbs are those from foods which contain a lot of fiber, such as whole grains or contain fiber and water such as fruit. The body takes longer to digest the good carbs so they enter the blood stream more slowly.

The longer food takes to digest the better. For example a piece of raw broccoli is better than cooked because your body has to work harder to digest the raw broccoli. The faster carbohydrates are digested, the more quickly they’re turned into sugar – glucose, and the more likely they will be turned to stored fat.

Fiber, protein and fats slow down the digestive system which means the blood sugar rises slowly and falls slowly. The tendency to over eat is diminished and the onset of hunger delayed.

The South Beach Diet limits fats and oils and encourages the consumption of lean cuts of meat and low fat cheeses. Vegetables and fruits are allowed after the initial phase I – two week period. Whole grains can be added back including whole grain bread. White breads, cookies, cakes, rice, potatoes, and sugar are off limits except for special occasions.

The South Beach Diet is a change in eating patterns for life, but other than the forbidden processed foods, white flour, and sugar, the diet is reasonably manageable. It allows a broader selection of foods than the Atkins diet.

The Atkins Diet is the grand daddy of the quick weight loss diets. It’s based on severely limiting carbohydrates. Carbs are processed by the body to become sugar or glucose. Glucose is used by the body for energy. If the carbs consumed for the day aren’t enough, the body transforms the fat it has stored back into glucose for energy.

Carbs also cause the blood sugar to spike which signals the body to produce insulin to remove the sugar from the bloodstream. This causes the blood sugar to drop which results in a craving for more carbs to raise it back up. That’s the basis of the Atkin’s Diet. Severely limit carbohydrates in the daily diet and the body has to fall back on its fat storage for energy.

The initial two week kick start program only allows 20 grams of carbs per day. The carbs from fiber are netted – subtracted from the total carb count. So for example, while ¼ cup of blueberries has a total carb count of 5.1 grams, only 4.1 grams are counted because 1 gram is from fiber.

Protein such as fish, chicken, beef, and pork contains 0 grams. The diet allows cheese and eggs. Seafood is tricky, some, like shrimp, have 0 grams and others like oysters, pack a walloping 12.5 grams per 6 oz.

You can have limited amounts of green vegetables such as spinach, kale, broccoli, asparagus, and cabbage. Fruit is not allowed. To give you examples of carb counts, an apple has a net 16 grams of carbs, a slice of wheat bread has 12 carbs. Alcohol in any form is not allowed during the kickoff stage. An exercise period of 30 minutes per day is mandatory.

After the initial two weeks, carbs are gradually and slowly added back to the diet, fruits and vegetables first. Some vegetables like sweet potatoes (19) and corn (14 per 1/3 cup) contain too many carbs to ever become a regular part of the diet. The maximum level of carbs at this stage should be between 30 to 35.

The objective is to continue losing weight but at a lesser rate than the initial two week period. If the weight loss stops the number of carbs being consumed has to decrease again.

The maintenance diet is at a level of carbs where you’ve stopped losing weight and don’t gain weight. It maxes out at about 40 grams of carbs per day. A turkey sandwich with mayo and sliced tomatoes is about 30 grams of carbs. A medium pear has 21 and one cup of 2% milk has 11.

Sugar, processed foods, flour and starches, such as potatoes and rice are pretty much off limits forever on the Atkins Diet. Most fruits have to be eaten in moderation if at all and certain vegetables as well.

Premenopausal women who were assigned to follow the Atkins diet for one year lost more weight when compared to women who were assigned to follow the Zone, Ornish and LEARN diets, according to a study in the March 7 issue of JAMA.

Overweight and obesity are well-documented problems in the United States. National dietary weight loss guidelines (a diet low in calories and fat, high in carbohydrates) have been challenged, particularly by supporters of low-carbohydrate diets. However, limited evidence has been available to effectively evaluate other diets, according to background information in the article.

Besides weight loss, the participants were also measured for lipid profile (low-density lipoprotein, high-density lipoprotein, and non-high-density lipoprotein cholesterol, and triglyceride levels), percentage of body fat, waist-hip ratio, fasting insulin and glucose levels, and blood pressure. Outcomes were assessed at months 0, 2, 6, and 12.

The researchers found that weight loss was greater for women in the Atkins diet group compared with the other diet groups at one year. Average 12-month weight loss was 10.4 lbs for Atkins, 3.5 lbs. for Zone, 5.7 lbs. for LEARN, and 4.8 lbs. for Ornish. At 12 months, measurements for lipids and levels of insulin, glucose and blood pressure for the Atkins group were comparable with or more favorable than the other diet groups.

The researchers found that weight loss was greater for women in the Atkins diet group compared with the other diet groups at one year. Average 12-month weight loss was 10.4 lbs for Atkins, 3.5 lbs. for Zone, 5.7 lbs. for LEARN, and 4.8 lbs. for Ornish. At 12 months, measurements for lipids and levels of insulin, glucose and blood pressure for the Atkins group were comparable with or more favorable than the other diet groups.

“Concerns about adverse metabolic effects of the Atkins diet were not substantiated within the 12-month study period.

While questions remain about long-term effects and mechanisms, these findings have important implications for clinical practice and health care policy