South Beach Diet vs. Atkins Diet - Different Approaches to Fat Loss


Atkins Diet Versus South Beach: Which Diet is Best?Credit:

If you’ve reached a point in your life where you realize you need to shed your excess pounds, but are not quite sure which diet plan is best for you, consider taking a little time to explore your options. Although the Atkins Diet and the South Beach Diet are popular low-glycemic weight-loss programs, and both work well, they each have different approaches to diet and fat loss.

Knowing the differences between the South Beach Diet and Atkins can help you make an informed decision as to which plan is right for you.

Atkins Diet Versus South Beach: What’s the Same?

Both weight-loss programs were created by cardiologists. Therefore, both plans can improve your cholesterol levels and lower your risks for cardiovascular disease. Both programs cut out simple carbohydrates such as sugar, starches, and white flour, so they help you manage your blood glucose levels and lower elevated insulin levels that can cause food cravings. They can also improve insulin resistance.

For that reason, both the Atkins Diet and the South Beach Diet are often referred to in the media and within the medical community as low-carb diet plans, but Dr. Agatston’s South Beach program isn’t a low-carb diet. It focuses on low-glycemic foods, which can sometimes be quite high in carbohydrates depending on your food choices.

Neither method is better than the other. Both are healthy diet programs, and both can help you reverse metabolic syndrome. They just go about it in different ways. 

Atkins Induction and South Beach Diet Phase 1 Differ on Carbs

The first two weeks of the South Beach Diet and the Atkins Diet are the most restrictive phases of each plan. Atkins Induction (now called Phase 1) has 12 rules that you need to follow in order to be successful. One of those rules is to “Eat no more than 20 grams a day of carbohydrate, most of which must come in the form of salad greens and other vegetables.”[1]

This amounts to about 2 cups of salad vegetables and 1 cup of higher-carb vegetables such as onions, cauliflower, summer squash, and Brussels sprouts, but if you pick non-starchy vegetables that are lower in carbs, you can eat more than that. Counting your carbohydrate grams is a major part of the Atkins Diet. It’s one of the things that set it apart from other low-glycemic plans. During the first two weeks, carbohydrates are severely restricted to 20 net grams, or less.

In comparison, the South Beach program doesn’t seek to eliminate most carbohydrates, but it attempts to replace what it calls “bad carbs” with “good carbs.” [2] To do that, it recommends you eat at least 4-1/2 cups of vegetables daily, including 1/2 cup of vegetables at breakfast. Since beans don’t raise blood sugar levels, Dr. Agatston also recommends that 1/3 to 1/2 cup of cooked beans replace part of your vegetable allowance at both lunch and dinner. Despite their high-carb content, beans are strongly encouraged for their nutritional value, but Dr. Atkins doesn’t allow beans for quite some time, if ever.

Unlike the Atkins Diet, there is no carbohydrate counting on South Beach, so for those who don’t enjoy counting or would have trouble giving up beans, the South Beach Diet might be a better fit.

In addition to beans, Dr. Agatston allows milk and low-fat dairy products from the very beginning of the plan. They are not limited. Plain, unsweetened yogurt, low-fat cottage cheese, and nuts are included in snacks and meals. Dr. Atkins chooses to return these higher-carb choices later on during the Ongoing Weight-Loss Phase (OWL) for those who miss these nutritious foods.

That makes the carbohydrate count much higher for South Beach Phase 1 than it is for Atkins Induction, unless you don’t like beans or nuts, or are allergic to dairy products and plan on doing the first phase of the South Beach Diet dairy free. Despite its higher carbohydrate content, most people who stick with the first phase of South Beach report dramatic weight losses during those first two weeks.

Standard American DietCredit:

Compared to the average American diet of 300 to 400 carbohydrates per day, even with beans and cottage cheese, South Beach Phase 1 is low enough in carbs to rev up your metabolism and give your weight-loss efforts a good head start. The same goes for Atkins, so your choice between the two plans will depend on how much you enjoy eating the type of foods allowed on each weight-loss program.

Returning Carbohydrates after Phase 1

Another major difference between Atkins and South Beach is how carbohydrates are returned to the diet after you’ve completed Phase 1. With the Atkins Diet, you can add a total of five grams of carbohydrates to your daily meals, per day, and then review the results at the end of the week. If you’ve lost weight that week and aren’t having any problems, you can add another five grams per day.[1]

The Atkins Diet recommends you continue adding carbohydrates very slowly, five grams at a time, in a particular order, provided you’re losing weight every week. This helps you individualize the plan to your own carbohydrate sensitivity. Eventually, you’ll reach a point where your weight loss stops. For some people that might be as low as 20 or 25 grams, or even less, while others can handle as many as 80 net carbs and continue to lose.

When your weight stops coming off, that defines where your individual sensitivity to carbohydrates is, so you lower your carbohydrates until you start losing weight again. The highest number of carbohydrates that allows you to continue burning your fat stores becomes your individual carbohydrate tolerance number for the rest of the diet.

With the South Beach plan, you return individual servings to your menus and snacks instead of counting carbohydrate grams. The first recommendation Dr. Agatston makes in his book is to add a piece of fruit and a serving of whole grains, and then see how it goes in a week or two.[2] If you’re still losing weight at a good pace, you are then allowed to add a serving of something else. Like Atkins, once you reach a point where your weight loss stalls, remove the last thing you added. That gives you your basic diet for the rest of the plan.

However, for many dieters, adding back fruit and grains that quickly during South Beach Phase 2 can cause them to stall with the very first addition. For many people, a slower approach such as a single piece of fruit, or even less, is best. Keep in mind that most people who turn to weight-loss programs are suffering from various types of metabolic damage. Repairing metabolic syndrome or improving insulin sensitivity doesn’t happen overnight. It takes time for the body to heal. Sometimes, that healing requires you to stay at Induction or South Beach Phase 1 for a few extra weeks. Don’t rush the carbs on either plan.

South Beach and Atkins Differ on Fats

The basic eating plan for the South Beach Diet consists of:

  • lean meats
  • non-starchy vegetables
  • low-fat dairy products
  • eggs
  • good fats, such as olive oil, nuts, and margarine

Saturated fats are limited because Dr. Agatston believes they are “bad fats.” He believes they cause artery inflexibility and make insulin resistance worse. He encourages you to eat “good fats,” which consist of fatty fish such as salmon and tuna instead. To help control calories, the daily recommended amount of added fats is about 7 teaspoons. The program recommends 1 tablespoon at lunch and another at dinner, plus 1 teaspoon for breakfast.

The Atkins Diet Allows You to Eat Chicken SkinCredit:

 In comparison, Dr. Atkins didn’t limit dietary fats, even saturated fats, and Atkins International continues to advise the same thing today. Dr. Atkins encouraged you to eat fats and protein liberally, until satisfied. These fats included:

  • fatty fish and meats
  • poultry, including the skin
  • mayonnaise, nut oils, and olive oil
  • full-fat dairy products
  • real butter

He also recommended using cold-pressed vegetable oils and cautioned readers against overheating polyunsaturated fats. To help control calories, there are limits placed on cheese, heavy cream, and sour cream.

Dr. Atkins believed that a dieter should not try to do a low-fat version of Atkins. He wrote it would interfere with weight loss and hurt a dieter’s efforts. However, he also emphasized fats should be used intelligently and reasonably, and that the purpose of using extra fat during the Induction phase was to help you overcome your food cravings.

Because of this unlimited restriction, some low-carb dieters have implemented a high-fat diet, but that type of eating style doesn’t work for everyone. In fact, if you take a close look at the recipes that Dr. Atkins used in his diet books, they are made with ground turkey, chicken cutlets, round steak, London Broil, and other lean meats as well as the fattier cuts.

Atkins Diet and South Beach Differ on the Necessity of Ketosis

Dr. Atkins believed the state of Ketosis was essential for fat loss.[1] With normal metabolism, glucose and fatty acids convert to fuel as needed, but elevated insulin levels can create a situation where the body is more inclined to store fats rather than mobilize them.

When you lower your dietary intake of carbohydrates, the liver mobilizes fats for fuel to keep your blood sugar levels normal. Ketones are a by-product of that process. When you are in the state of Ketosis, fatty acids are predominantly burned for energy, rather than glucose. However, the body still burns glucose when it’s available because despite the adverse publicity, the Atkins Diet is not a Zero-Carb Diet.

While the South Beach Diet also works on the principle of reduced carbohydrate intake, Dr. Agatson doesn’t believe you need to restrict carbohydrates as drastically as the Atkins Diet does.[2] Some people may enter the state of Ketosis while following South Beach principles, but it isn’t required to lose weight with the program. A lot depends on your degree of insulin resistance, how active you are, and the foods you choose to return to the basic diet plan.

Rather than Ketosis, South Beach focuses on the glycemic-index response to foods. The following video explains what the glycemic index is, and how it affects your blood glucose levels. She also explains what net carbs are.

Atkins Diet Versus South Beach Diet

What are the Glycemic Index and Net Carbs?

South Beach Phase 1 effectively uses foods that are low on the glycemic index. Dr. Agatston believes that foods such as vegetables, beans, and low-fat dairy products help to lower your insulin levels because they don’t cause your blood sugar to rise after you eat them. These types of foods enable your metabolism to function normally.

However, dairy products are inflammatory. They secrete insulin without the need for a rise in blood sugar. In fact, according to Dr. Terry Shintani, "Most dairy products raise insulin levels 90 to 98 percent as high as white bread does."[4]If you happen to be sensitive to dairy, you'll need to restrict the amount you eat, and maybe even completely eliminate it in order to lose weight.

How to Choose Which Weight-Loss Program is Best

The ultimate question is how to decide which weight-loss program will give you the best results. The answer depends on your sensitivity to insulin, as well as how you choose to implement each of these diet programs. Those with insulin resistance tend to have higher insulin levels overall, because the body has to release additional insulin in order to overcome the resistance.[3]

Sometimes, insulin problems are hereditary, and sometimes they result from lifestyle choices and diet. However, few physicians will test their patient’s insulin levels to find out. These days, the focus is more on diabetes, and if you test normal for that, or even pre-diabetic, the topic of elevated insulin levels is generally dropped. That’s because insulin testing can be expensive and complex. It’s much easier to simply treat diabetes.

However, Lyle McDonald, a well-experienced personal trainer and bodybuilder, explains in his article about insulin sensitivity[3] that there is a way to figure out which type of diet is best for you. You can do that by asking yourself the following questions.

When you eat a high amount of carbohydrates (starches, sugars, and grains):

  1. Do you feel good and energetic?
  2. Or do you feel tired, bloated, and washed out?
  3. Can you maintain your energy levels throughout the day?
  4. Or do you experience what some people refer to as a crash?
  5. Do you get sleepy and hungry a short time after eating? 
  6. Or do you feel satisfied and happy for long periods of time?

Good insulin sensitivity will make you feel good, energetic, and satisfied without experiencing the blood-sugar lows, bloating, and drained-out feeling that insulin resistance gives you. Those who crash and get hungry quickly after a high-carb meal are probably over secreting insulin, because higher levels of insulin make you feel tired and hungry.

While both the Atkins and South Beach diets claim to correct insulin resistance, the bottom line is still the amount of carbohydrates you take in, and your body’s reaction to them. The degree of insulin resistance and overproduction of insulin required to compensate will vary greatly from individual to individual, so the best diet for you will depend on how you answer the above questions.

Those who can handle a higher amount of carbohydrate will do well on the South Beach Diet. Those who can’t would do better on an Atkins type diet. If you fall somewhere in the middle, or don’t want to bother with counting carbohydrate grams, you can find success modifying your diet to include some of the principles found in both plans.

However, your body’s reaction to dietary fats is also an important factor. If you lean toward being a sugar-burner, rather than a fat-burner, you’ll feel terrible and remain hungry when you enter the state of Ketosis, and won’t completely adapt to that condition – even after several weeks. How you feel in Ketosis depends on your ability to convert body fat into energy, as needed. Some people have a harder time, than others. They may have difficulties getting into Ketosis, and staying there, or they may never make the switch.

The same thing will happen if you are very insulin sensitive, rather than insulin resistant. Regardless of what many within the low-carb community believe, overweight is not always a sign of insulin resistance. You can actually be insulin sensitive, and you can have problems secreting enough insulin to handle the amount of carbohydrates you’re currently eating. In addition, an Atkins type diet can cause your insulin levels to plunge too low. It's also problematic for those with fat malabsorption issues.

In that case, the South Beach Diet or a higher-carb, lower-fat version of Atkins might be a better fit. However, you won’t be able to make that kind of determination until you first give the standard Atkins Diet a try.