Forget the keto diet. Everyone is chattering about The Dubrow Diet right now. (It’s the #1 new nutrition release on Amazon.) And it’s got some big, life-changing promises.

If the name sounds familiar, that’s because it is. The Dubrow Diet is from reality TV power couple Heather Dubrow and Terry Dubrow, MD. She of Real Housewives of Orange County fame, and him a Newport Beach plastic surgeon and star on Botched. Their book is all about how to go on a diet that leaves you feeling and looking as good as they do.

So, what’s the huge secret? Intermittent fasting. Right, not such a huge secret, considering that next to the keto diet, IF is the next hottest thing. There are several ways to do intermittent fasting, but the Dubrows stick to time-restricted fasting. This means you only eat during a certain window of time in your day, and fast the rest of the hours. For example, you may fast for 12, 14, or 16 hours a day. They call this a “reset” (fast) and “refuel” (feast) schedule.

In their book the Dubrows present the research on intermittent fasting as definitive. But the reality is, it’s still emerging. The authors of a 2015 review of 21 studies concluded that while certain types of fasting have been found to help people lose weight and body fat, the data on time-restricted fasting is limited, and “clear conclusions cannot be made at present.” In 2017, a position statement from the The International Society of Sports Nutrition noted that there isn’t any evidence that intermittent fasting is more effective than cutting calories.

Cynthia Sass, MPH, RD, Health’s contributing nutrition editor, agrees that it’s too early to draw conclusions about IF: “We’re still learning about the potential health benefits of intermittent fasting in healthy adults, including if it’s the best approach for long-term weight loss.”

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How does the Dubrow Diet work?

Get ready, because there are three phases and many rules within each:

Phase 1: Red Carpet Ready

You commit to a “two- to five-day metabolic boot camp” of a 16-hour reset (fast) and 8-hour refuel (feast). This is meant to reset your hunger and fullness cues.

Phase 2: Summer Is Coming

This phase is done until you reach your goal weight. How quickly you want to get there determines how long your “reset” period will be. For instance, if you want to do it fast, you’d stick with a 16-hour reset and 8-hour refuel window. You also get to “cheat”—either for a “moment,” a “meal,” or an entire “day,” depending on your fasting schedule. Your eating time may start at about 1 p.m. with lunch (before that you’d have coffee, or a green/beet drink that they heavily promote), followed by a light snack, and then dinner.

While the Dubrows don’t encourage counting calories or macros, they do have guidelines for what you should eat in a day. In this phase, that includes:

Protein: 2-3 servings per day

Fat: 2-3 servings per day

Nuts, seeds, and snacks: 1 serving per day

Dairy: 1 serving per day

Veggies (those that grow above ground are preferred): 2-3 servings per day

Fruit: 1-2 servings a day

Complex carbs: 1 serving per day

And, good news, you get to drink alcohol—something low in sugar (like wine or brut champagne). Women are encouraged to stick to one drink per night. But if you have this glass of wine, cut your fruit to one serving per day.

Phase 3: Look Hot While Living Like a Human

In the maintenance phase, you stick with the basic plan outlined in phase 2 indefinitely. (The old “if it’s not broke, don’t fix it” reasoning.) That means a 12-hour fast five days a week; and a 16-hour fast twice a week. Here, the idea is that you find your groove so that the rules become more automatic, and the whole thing becomes easier to sustain.

RELATED: 10 Foods to Eat More of If You’re Trying to Lose Weight, According to Nutritionists

What a nutritionist thinks

Exhausted yet? The phases and differing fasting lengths can make this a more complicated plan to follow, Sass notes.

One plus, says Sass, is that the diet emphasizes whole foods, veggies, lean proteins, and healthy fats. And it doesn’t require eliminating carbs completely. But there are some big minuses: “The diet feels outdated, as far as the phases, the very low-calorie levels, and the emphasis on body image,’’ says Sass.

Let’s chat about those calorie levels. Though the Dubrows say you shouldn’t count calories, the reality is that their diet is quite low in calories. When you’re only eating in an 8-hour window, there’s simply less time to eat (which is one reason why intermittent fasting may be effective in the first place). Couple that with the limited servings of foods you’re eating, and you may be getting around 1,000 to 1,200 a day, at least in the first two phases.

“Limiting calories this much goes below the amounts generally needed when you’re completely sedentary,” says Sass. “So, you’re eating less than it takes to support your body if you were to lay in bed all day and do nothing. This kind of deficit isn’t dangerous short-term, but it’s not necessary, and it can contribute to irritability, mood swings, persistent hunger, and cravings,” she says.

RELATED: 57 Ways to Lose Weight Forever, According to Science

Another caveat: The Dubrow Diet is also…a diet. There’s a lot of emphasis on staying “hot” or bikini ready. But that approach can be problematic, as Sass points out. “Weight loss should be a side effect of developing a healthy, balanced, and sustainable relationship with food. When body image—getting red carpet ready, getting a bikini body—is the focus, it can lead to an overly restrictive mindset that can trigger under-nourishing, which is not healthy physically or emotionally, and not maintainable long-term,” says Sass.

Aside from promising physical results, The Dubrow Diet also presents itself as your be-all and end-all for confidence, happiness, motivation, and boundless energy. But any diet that claims it will change your life should raise a red flag. (Besides, a plan that encourages a preoccupation with exactly what you’re eating and when in order to look a certain way—rather than making healthy decisions in the context of a full life—can suck the joy out of things real quick.) Bottomline: approach with caution.

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