The Keto-Friendly South Beach Diet
Remember the South Beach Diet? It’s back with a keto twist. Here’s how it can help you beat sugar addiction, burn fat, and achieve lifelong health.
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Sugar addiction is the same as alcohol, cigarettes … any addiction,” says Arthur Agatston, MD, author of the South Beach Diet and his latest, The New Keto-Friendly South Beach Diet. But you can beat it, he adds—for good.
As someone who has struggled with his own sugar addiction, Agatston knows the pitfalls of diets only too well. “When I put weight on my belly after I cheated, my wife would say, ‘Arthur, you can only do radio,’” he recalls.
But rather than giving up, he found the lasting cure. “I feel so much better. I really call it the fountain of youth,” he says after staying slim and full of energy for the past year and a half. And the same holds true for his patients who’ve adopted these new eating habits.
What’s New
Agatston’s new diet lowers carbs enough to turn on enzymes that burn excess body fat, but not so low that it’s difficult to maintain. And it ends the pattern of eating throughout the day—the popular pastime of “grazing.” In terms of the underlying science, it combines two effective principles: the keto diet and intermittent fasting.
Agatston has found that for most people, eating a bit more unprocessed carbs and protein than you would in the very-low-carb keto diet can produce comparable benefits. But it’s easier than a “diet” that inevitably ends one day.
Timing of food is equally important. For years, many nutritionists have believed that small, frequent meals—every three hours or so—were essential to keep levels of blood sugar stable and prevent cravings. Not so, says Agatston; “We now know they do the opposite.”
Why Eating Often Is Deadly
You probably know that eating carbs raises blood sugar, and then insulin levels rise in response and blood sugar drops. It’s a normal reaction, but eating too often can make it go haywire.
With frequent meals or snacks, insulin rises significantly more than it would with fewer meals. Even if you ate the same amount of food in one large meal, your insulin would rise significantly less.
“When your insulin levels are high, they’re blocking access to fat,” says Agatston, “So, you’re walking around hungry all the time, even though you have a lot of excess fat.”
High insulin is what enables bears to gorge and continually gain weight through the summer and early fall. “Bears are ravenously hungry even though they have 400 pounds of stored fat,” he says; “They can eat 30,000
berries per day.”
Consequences of High Insulin
Over time, insulin levels become chronically elevated. In addition to fostering obesity and making lasting weight loss impossible, elevated insulin leads to many of today’s chronic health problems, including:
- High blood pressure
- Reduced immune function
- Inflammatory belly fat
- Diabetes
- Prediabetes
- Fatty liver disease
- Atherosclerosis
- Memory lapses and mental decline
- Increased risk for breast, gastric, colon, pancreatic, and liver cancers
Hidden Insulin Danger
“Most Americans are walking around with high insulin,” says Agatston. It’s a problem even among teenagers. Yet, most doctors aren’t aware of the danger.
Outside of diabetes treatment, insulin isn’t routinely checked as a marker of health. And in the rare cases where an insulin test is performed, it measures only fasting insulin rather than the real danger—disrupted insulin patterns.
In truly healthy people, insulin levels peak about 30 minutes after eating and then gradually drop back to their baseline within an hour or two. With too much sugar, processed carbs, and frequent meals and snacks, insulin takes longer to peak and longer to drop. And then, it stays chronically high, keeping you chronically hungry.
Elevated insulin keeps blood sugar levels in a normal range for decades, masking the underlying problem. But eventually, blood sugar will also rise, and that’s when prediabetes or type 2 diabetes is diagnosed. Meanwhile, elevated insulin levels have been causing damage for years. Agatston sees people in their 30s, or even younger, with plaque in their arteries because of high insulin. But their blood sugar levels are normal.
“When your insulin levels are high, they’re blocking access to fat,” says Agatston, “So, you’re walking around hungry all the time, even though you have a lot of excess fat.”
The Real Insulin Test
Although few doctors outside of research settings are familiar with it, there is an insulin tolerance test that Agatston uses to detect abnormal insulin patterns. It requires several blood samples: before you have a glucose drink, 30 or 60 minutes later, and again after 90 and 120 minutes. If insulin takes more than 60 minutes to peak, or if it’s higher at 120 minutes than it was at 60 minutes, there’s a problem.
For more information about the test, you can search “insulin response to glucose” at questdiagnostics.com. You will need to work with a health professional.
However, if you’re struggling with hunger, low energy, weight, mental focus, high blood pressure, prediabetes, type 2 diabetes, or heart disease, a diet that promotes healthy insulin function can help turn things around.
Keto-Friendly South Beach Diet Snapshot
Agatston’s diet sets up a low-carb lifestyle in two phases:

Phase 1: A stricter low-carb regimen for at least a month, until you’re no longer addicted to sugar and have reached certain milestones, including increased energy and endurance; no cravings or frequent hunger during the day; decreased belly fat and waist size; and normal levels of blood sugar. You may or may not have achieved your weight-loss goal, but the rate of loss has slowed down. Aim to eat no more than 50 grams of carbs per day.
Phase 2: The lifestyle eating approach from here on out, with the introduction of some additional carbs. If you haven’t reached your weight-loss goal in the first phase, you’ll continue to lose weight more gradually. Aim to eat no more than 100 grams of carbs per day.
In both phases, these are the most important things to do:
- Stay away from sugar and refined carbs.
- Eat fewer, larger meals rather than frequent small ones.
- Eat whole foods rather than processed or packaged ones.
- Eat a variety of non-starchy vegetables.
- Eat a variety of meats, poultry, and seafood.
- Include healthy fats such as almond, avocado, coconut, MCT, hazelnut, sesame, and olive oils, but not vegetable oils or refined oils.
- Include full-fat dairy products and eggs.
- If you have snacks, keep them low-carb, such as a small handful of nuts.
- Eat slowly.
Phase 1 and 2: Similarities and Differences

A typical plate would look similar in both phases, with non-starchy vegetables filling at least half and the rest being a protein such as meat, poultry, seafood, or low-carb vegan protein. Soda, sugar, corn, wheat, and potatoes aren’t on the menu in either phase. And preferred sweeteners should always be stevia, monk fruit, or erythritol.
While following the main rules above, there are foods and drinks forbidden in phase 1 that can be added in phase 2, including:
- High-protein grains (1 serving = ½ cup) such as amaranth, buckwheat, oats, quinoa, and wild or brown rice.
- Small servings of some starchy vegetables, such as sweet potato or yam (1/2 medium one), winter squash (1/4 cup), calabaza squash (1/2 cup), and pumpkin (1/4 cup).
- Lower-sugar fruits such as berries, starfruit, apples, apricots, peaches, and melons.
- Alcoholic drinks no more than twice a week, such as a 11/2-ounce serving of spirits, a 4-ounce glass of wine, or a low-carb beer.
Throughout the process, and especially in phase 2, Agatston encourages each individual to be aware of how they react to different foods. If symptoms of sugar addiction, frequent hunger, or cravings return, be more vigilant in controlling carbs to get back on track. The overall goal is to learn as you go and develop eating strategies that work for you. Detailed menus and recipes are included in The New Keto-Friendly South Beach Diet.

Click here for the Sesame Glazed Beef & Veggie Bowl recipe.