South Beach Diet: How It Works, Phases, Pros and Cons, and More

In the 1990s, the Miami-based cardiologist Arthur Agatston, MD, set out to change the way his patients ate by creating his own healthy diet to protect against serious medical conditions like heart disease and type 2 diabetes.

The diet took its name from Dr. Agatston’s area of practice, according to the South Beach Diet website, and the approach quickly became popular in the Miami area.

Dr. Agatston’s weight-loss plan was published in 2003 as The South Beach Diet, which has since sold millions of copies.

What Is the South Beach Diet, and What Is Its Purpose?

The South Beach Diet eliminates refined carbohydrates — white flour and sugar are the top culprits. People on the plan are urged to curb carbs and focus on lean protein, low-fat dairy, and healthy carbs — including whole grains, vegetables, and fruit — as a way to lose weight, improve their health, and reduce the cravings that put you in the typical hunger-overeat-gain-weight cycle.

In addition, the South Beach Diet doesn’t shy away from some types of carbs: “South Beach in the long run encourages a diet that includes complex carbs — whole grains, beans, lentils, etc. — and fruits,” says Natalie Stephens, RD, at the Ohio State University Wexner Medical Center in Columbus, Ohio. “If followed as originally recommended, the South Beach Diet ends up looking similar to the DASH diet: lots of vegetables, fruits, nuts, lean meats, plant-based oils (not coconut oil), and low-fat dairy. That’s actually a very science-based diet.” Stephens notes that such diets have shown health benefits like lowering cholesterol levels and lowering high blood pressure.

An important emphasis of the South Beach Diet is controlling hunger by eating before it strikes. To that end, the South Beach Diet includes three different phases: Phase 1 is two weeks long and aims to “reset your body” to help burn fat and increase your metabolism, as well as reduce sugar and starch cravings. Phase 2 is for steady weight loss, where you add in good carbs to your diet. Phase 3 is the weight-maintenance phase, where you learn to maintain your new weight without deprivation or hunger. (3)

“The phases help ‘jump-start’ some weight loss,” Stephens explains. “It’s a mental thing: When patients see early success, they’re more likely to stick to the plan.” She notes that the different phases also help acclimate people to a new lifestyle, since phase three is essentially a lifelong choice rather than a “diet.”

Here’s a look at the three-phase program.

Like all the phases of the South Beach Diet, phase 1 allows you to eat three meals, one dessert, and two snacks every day. However, phase 1 of the program is the most limited in terms of food choices: You can eat only lean sources of protein, high-fiber vegetables and legumes, nuts, low-fat dairy including certain cheeses, and good-for-you unsaturated oils like olive oil.

Phase 1 lasts two weeks.

The goals of this phase are to wean you off all the junk food you’ve been eating, limit choices so you don’t have to overthink your diet, and stop cravings by getting your blood sugar under control.

“The way to control overeating is to control blood sugar and your insulin response by eating every three to four hours, and eating a high-fiber diet with whole grains, fruits and vegetables, and heart-healthy fats,” says Barbara Schmidt, RDN, who is in private practice in New Canaan, Connecticut.

Refined carbs affect blood sugar control. Have too many refined carbs at any one time — a big bagel, for instance — and you’ll be hungry again sooner, and more apt to eat something you shouldn’t be eating, explains Schmidt, adding that, on the whole, the South Beach Diet restricts those troublesome carbs better than other diets.

A Sample Menu of Phase 1 of the South Beach Diet

Here is a suggested menu for phase 1 from the South Beach Diet website: (4)

Breakfast South Beach Complete shake

Snack Plain Greek yogurt with fresh dill and lemon juice, along with celery sticks and cherry tomatoes

Lunch Grilled chicken, ½ an avocado, and cooked broccoli

Snack South Beach Diet Peanut Chocolate Bar

Dinner Baked salmon, white beans, sautéed cabbage and garlic

Evening Snack Almonds

In phase 2 of the South Beach Diet, you’ll add whole grains and fruits to your diet, and you will stay on this phase of the weight-loss plan until you reach your goal. “These carbohydrate-rich foods are high in fiber and [are low on the] glycemic index — these good-carb choices have more staying power, take a long period to be processed and absorbed by the body, and prevent the purported fluctuations in blood glucose and quick secretions of insulin,” explains Susan Kraus, RD, a clinical dietitian based in New Jersey.

According to the South Beach Diet website, in phase 2, you can have: (5)

• 1 serving per day of fruit, such as a small banana, 2 medium plums, or a cup of mixed berries (such as strawberries and blueberries)
• 1–2 servings per day of starchy vegetables such as ½ cup of winter squash or sweet potato
• Some good carbohydrates, such as 3 cups of air-popped popcorn, 1 small tortilla, etc.

You will still want to avoid foods like:

• Refined carbs, including white bread, white pasta, and rice cakes
• White potatoes
• Fruit juices
• Dried fruits with added sugar
• Sweets like ice cream, honey, and jam

A Sample Menu of Phase 2 of the South Beach Diet

Breakfast Breakfast pita with spinach, eggs, and feta cheese, vegetable juice, and tea or coffee

Snack Assorted vegetables with a cilantro and pesto dip

Lunch Curried turkey and greens salad

Snack Apple and peanut butter sandwiches

Dinner Edamame appetizer, Louisiana-style shrimp and rice, baked tomatoes topped with Parmesan cheese

Dessert  South Beach Diet–style tiramisu

The South Beach Diet aims to be a plan for life: Phase 3 lasts indefinitely. You learn how to eat other foods in moderation to keep from regaining lost weight and having to go on another diet.

If you need recipe inspiration or are looking for additional variety, check out DASH diet cookbooks, Stephens recommends, as the two diets are very similar.

A Sample Menu of Phase 3 of the South Beach Diet

Stephens says this is what a day of eating in phase 3 of the diet may look like:

Breakfast Mini crustless quiches (eggs with peppers, onions, and cheese baked in a muffin tin) with a slice of whole-grain toast like Ezekiel bread, a cup of berries, and a cup of black coffee or tea

Lunch Salad greens with salmon or chicken and olive oil and vinegar dressing

Snack Greek yogurt with berries

Dinner A plate filled with half-roasted vegetables (zucchini, squash, red onion), a small, 4-ounce portion of lean meat (such as salmon, chicken, or beef tenderloin), and 1/3 cup of a hearty grain (farro, quinoa, barley)

Dessert Mascarpone cheese or Greek yogurt with peaches, topped with slivered almonds and cocoa powder

The Best Resources for People Following the South Beach Diet

To find the most up-to-date information on the South Beach Diet, you can visit the South Beach Diet online, which has a bank of resources and tools to help you, including:

• Support groups
• Hundreds of recipes
• A program that will create your food shopping list for you

(Note: SouthBeachDiet.com, the only official and authorized website for the South Beach Diet, is part of the Everyday Health network.)

You can also check out the book The South Beach Diet Supercharged, which includes information on additional foods and recipes, as well as workouts to complement the diet.

“This plan is presented very simply, no measuring for many of the foods is necessary, especially at the beginning,” says Kraus. “Due to the strictness of phase 1, some people could have a significant amount of weight loss in the first two weeks, [such as] 8 to 12 pounds. Phase 1 could help stop cravings for highly refined carbs, and the foods recommended throughout the plan are heart healthy.” Blood sugar control has the added bonus of helping control type 2 diabetes if you already have it.

Schmidt likes that “the South Beach Diet tells you what to have and when to have it. Also, it was always about fiber,” which is a definite plus considering fiber is satiating and can help you maintain or achieve a healthy weight.

Also, because the diet limits carbohydrate consumption, it could have some additional beneficial effects. David Ludwig, MD, PhD, a professor in the Department of Nutrition at Harvard T.H. Chan School of Public Health, noted in a post on the Harvard School of Public Health site that “fad diets” like South Beach and Atkins can, by helping limit the amount of processed carbs people eat, produce tangible health benefits for people backed up by sound scientific reasons. (6) That’s because the quickest way to stabilize blood glucose and lower insulin levels is to reduce processed carb intake, he says.

The South Beach Diet might represent the ultimate eating plan for some, but it may not be perfect for everyone.

For one thing, Schmidt says the diet doesn’t provide enough calcium, which is especially important for women because they are more prone to osteoporosis, or bone loss. Getting a sufficient amount of calcium in your diet can help build and maintain strong bones and ward off bone disease.

Although guidelines include 2 cups of dairy (like milk and cheese) per day, this isn’t enough. “You absolutely need a calcium supplement, 500 milligrams with vitamin D, in the morning and in the evening. I also don’t like the idea that there’s no fruit and no starch during phase 1,” says Schmidt, though this is less of a problem if you’re only on it for the two weeks. Focusing on other calcium-rich foods that the diet allows, such as leafy greens, is another way to boost calcium intake.

Phase 1 is stringent and, because of the limited nature of certain foods, some people might have a tough time following it, especially when they’re away from home, Kraus says. “There are no specific recommendations for portions for many of the food groups.” This could lead to overeating or even undereating.

And some studies haven’t found any benefit of the South Beach Diet over other popular diet programs. For example, a 2014 review looked at the effectiveness of the Atkins diet, the South Beach diet, the Zone diet, and the Weight Watchers diet, and researchers did not find evidence that any one plan was significantly more effective than the others. (7) (Of them all, at 12 months, the Weight Watchers diet appeared most effective at reducing weight.)

If you decide to try the South Beach Diet, you may notice certain changes in your health and weight during each phase.

“People will see immediate results due to the strictness of the first phase,” says Kraus. “Adding back food might slow down weight loss a bit, but it should continue as long as the dieter follows the plan as recommended.”

The South Beach Diet aims to be a lifelong eating plan that you adapt when you reach the maintenance period, which is phase 3. By this point, you have learned how to eat in a healthy way, meaning you can have occasional treats, like a slice of cake, but by using what you learned in phases 1 and 2, you keep yourself from veering too far off the plan.

“It has all the right kinds of foods you should be eating,” Schmidt says. “In the long term, if you follow it Monday through Friday, and on the weekend give yourself a little leeway, you’ll maintain. It is more restrictive, but there are fabulous recipes and tons of them.”

According to Agatston, the diet’s creator, the long-term effects of following the South Beach Diet — beyond just losing weight — include lowering your cholesterol, along with your risk of heart attack, stroke, diabetes, and even some cancers. 

However, it’s important to note that there is little to no research supporting these claims. In addition, one 2006 report reviewed all the nutrition facts presented in the South Beach Diet and found that more than 67 percent of them may not be supported in the peer-reviewed literature.

“The diet can work for some people, not all people,” Stephens says. Crucially, she says that people need to move past the word “diet” and focus more on lifestyle changes.

Lean proteins and lots of vegetables, fruits, and whole grains are cornerstones of most eating plans aimed at maintaining a healthy weight and preventing and treating chronic diseases.

Additional reporting by Stephanie Bucklin