February 22, 2016
The South Beach Diet is a weight-loss diet first popularized in 2003 by cardiologist Arthur Agatston and outlined in his best-selling book, “The South Beach Diet: The Delicious, Doctor-Designed, Foolproof Plan for Fast and Healthy Weight Loss.”
It is important to understand from the outset that the South Beach Diet is a commercial weight-loss diet that makes money for those who sell its various products. There are many South Beach Diet products, including conveniently pre-packaged foods and cookbooks widely available both in stores and online. Commercial diets that provide accessible foods and are easy to follow also provide a steady profit stream to those selling its products. However, you don’t actually need to buy the products in order to follow the diet.
The South Beach diet, which is named after a glamorous area of the city of Miami Beach, is a “modified” low-carbohydrate diet. It is lower in carbohydrates and higher in protein and fats than is found in most typical weight loss diets of its era. However, it is not an extremely low-carbohydrate diet. And in that respect, it is actually easier to follow for protracted periods of time.
The South Beach diet employs the glycemic index of foods and glycemic load (their relative amount) to explain which carbohydrates a person should avoid. There is some evidence that increases in blood sugar resulting from high glycemic foods can boost appetite and therefore increase both food consumption and weight gain. Over the long term, weight gain and associated insulin sensitivity can contribute to many forms of cardiovascular disease.
The South Beach Diet distinguishes those dietary fats that are said to be “good” from those that are “bad”. It also limits fats that Dr. Agatston argues are unhealthy while emphasizing foods with “healthier” (monounsaturated) fats.
The South Beach Diet also emphasizes the consumption of whole grains and increased amounts of dietary fibre. Many fruits and vegetables are also part of the South Beach Diet.
The main goal of the diet is to alter the ratio of the foods most people already consume in order to encourage weight loss and a healthier lifestyle. Dr. Agatston suggests that a ratio of higher protein and lower carbohydrates than is commonplace is a healthier way of eating whether you want to lose weight or not. For many people this actually may be true, but it is not true for everyone. It depends on where one starts, how active a lifestyle one already has, and many other individual factors.
One of the attractive aspects of the diet—and probably the reason it is still popular—is that people find they can adhere to it for a sustained time period, perhaps even over a lifetime.
The diet itself is a three-step program:
- the first phase eliminates many high glycemic items in order to reduce cravings and induce some relatively quick weight loss.
- the second phase slowly reintroduces some of these in smaller amounts and in an altered ratio with proteins in order to continue weight loss.
- the final phase is a maintenance diet designed to keep weight off. The diet emphasizes that in phase three, all kinds of foods can eventually be eaten in moderation, including some snacks and desserts which you can buy over the counter, as well as make for yourself.
Does the South Beach Diet actually work?
There are no specific long-term, randomized controlled clinical trials that we know of that are designed to measure the health outcomes of the South Beach Diet.
There have been no studies of the overall health or cardiovascular benefits of following a low-glycemic-index diet in healthy adults either. While eating foods like whole grains, unsaturated fats, vegetables and fruits could help to promote better health for many people, none of these very general items are inherently good for everyone. Some whole grains, for example, have high gluten content that can be very difficult for some people, while others do not. Some saturated fats are not a problem, and not all unsaturated ones are actually good for you. And vegetables and fruits vary greatly in their vitamin, fibre, sugar, and caloric content.
While altering the ratio of protein to carbohydrates is likely to lead to weight loss in the first phase of the diet, at least in part because that also reduces caloric intake, it is overly simplistic to suggest that this simply reduces cravings, though in some individuals it may do so.
Are there risks to the South Beach Diet?
The South Beach Diet probably has little risk because the first phase of the diet is short, and it only alters the ratio of foods already consumed.
Severely restricted carbohydrate diets do lead to ketosis, where the body uses stored fat for energy, and in some individuals this can lead to discomforts including nausea, headache, mental fatigue, and occasionally dehydration and dizzy spells. Bad breath is also often reported when the body is in ketosis. However, the South Beach Diet is not a severely restricted carbohydrate diet so most of these problems are not likely if one is actually following the recommended three sequences of the diet.
Speaking with a knowledgeable professional before starting this (or another) diet is a good idea, especially if you have any health concerns or are taking any form of medication. And prior to beginning any diet plan it’s also a good idea to read about its limitations, then evaluate the diet and formulate your own views of its recommendations in a balanced way.
The most trenchant online critique of the South Beach Diet is probably one written by Joseph Mercola.
Mercola’s criticism is quite detailed and we recommend reviewing it on your own. However, it can be summarized as follows:
- There are inaccuracies around carbohydrates especially with respect to normalizing insulin levels
- toxin levels in fish are underestimated, and the costs of relying on them in a diet are exceptionally high
- milk allergies associated with caselin are problematic
- saturated fats from healthy sources are actually good (not bad) and we need more of them
- artificial sweeteners (aspartame) are unhealthy
- trans-fats are dangerous and ought to be avoided at all costs
- carcinogenic oils such as those in peanuts containing traces, or more of afflatoxin are dangerous
- the dangers of dependence on statins is unrecognized
- weight loss will not occur in many individuals;
- and finally, too little exercise is recommended.