The diet is broken down into three phases, as outlined by the Mayo Clinic:
Phase 1 – This stage lasts only two weeks and is the most restrictive. Almost all carbs are eliminated during this phase, which is designed to jump-start weight loss and eliminate your cravings for refined starches and foods that are high in sugar.
Phase 2 – This long-term weight loss phase is less restrictive and should be followed until you reach your goal weight. You can add in some, but not all, of the foods that are restricted in the first phase.
Phase 3 – After you've reached your goal weight, you're supposed to take the principles learned in the first two phases to eat healthier for the rest of your life. Most foods are OK to eat in moderation at this point.
The diet also encourages exercise, including walking and exercises designed to strengthen your core.
Foods that are encouraged
The South Beach Diet calls for plenty of the following types of foods:
- Low-fat dairy
- Those that have a low glycemic index, so they don't have a large impact on your blood sugar
- Lean protein, including chicken and turkey
- Whole grains
- "Good" fats - such avocado, canola oil and extra-virgin olive oil
Foods to avoid
The following types of foods should be limited:
- Fatty meat and poultry
- Some fruits - including dates, figs, pineapple, raisins and watermelon
- All fresh and frozen fruits are allowed in phase 2 and 3 except dates, figs, pineapple, raisins and watermelon. Start phase 2 with a single serving of fruit a day, working up to a maximum of three servings a day.
- Butter and coconut oil
- Whole milk
- Foods made with refined sugar
- Honey, maple syrup and agave nectar
What's the verdict?
The Mayo Clinic says the South Beach Diet can yield some health benefits. If you eat more healthy carbs and more healthy fats in the long-term, you can see health benefits that go beyond weight loss, such as lowering your cholesterol levels.
It views the diet as generally safe, but cautions against restricting carbohydrates too severely. This can cause ketosis, a process caused by insufficient sugar in your body. Without enough sugar to use for energy, your body will break down stored fat, and you can experience ketosis and its side effects, including nausea, headache, mental fatigue and more.
In addition, experts told U.S. News & World Report that the first part of the diet is a little heavy on fat and that phases one and two may not contain enough carbs. They also caution people with kidney problems that the diet may not include enough potassium.
However, it also said that you should feel full while you're following this diet, because it contains plenty of fiber. This is also true since snacks are encouraged in order to help prevent you from getting hungry.