Liz Neporent is a diet and fitness expert and author of 12 fitness bestsellers. She regularly appears on national TV programs and is the president of Wellness 360, a New-York based wellness provider. You can also follow her on Twitter @lizzyfit.

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Limiting sugar and carbs will help me drop belly fat – Fit or Fiction?

In his new diet book, "The Belly Fat Cure," Jorge Cruise reveals the No. 1 one secret to getting healthy – fast! "It all comes down to knowing how to eat the correct amount of sugar and carbs -- what I call the S/C Value. Without this ratio, you will fail to produce the hormone leptin, and you will store belly fat," Cruise tells readers. A client of his who went on the diet lost an unprecedented 13 pounds in one week as a result of eating chocolate, Dortitos and ice cream.

It is at this point I take a deep breath and count to 10. I met Jorge a few years back while on a publicity tour for one of my books. At the time he was touring for his book, "The 3-Hour Diet Cookbook." He seemed like a pretty nice guy, so I in no way mean it personally when I say that he either doesn't have a grasp of basic science or he is just flat out making this stuff up. (Full disclosure: His book did a lot better than mine.)

The S/C ratio stands for Sugar/Carb ratio. After spending well over an hour speaking with several registered dieticians, I will attempt to explain this theory: According to Cruise, your S/C ratio should be no greater than 15 grams of sugar and six servings of carbs per day. Without this ratio, Cruise claims, you will fail to produce the hormone leptin, and you will store belly fat. The S/C ratio also seems to be something that he assigns to individual foods (a chocolate bar with a 21/1 ratio, bad; one with a 5/1 ratio, good). I literally cannot understand how this system is supposed to work for both stand-alone foods and the overall diet; I am good at math, and I really tried. Sorry.

So let's start with the first premise which is implied in the very name S/C Ratio. According to registered dietitiain Ruth Frechman, owner of On the Weigh in Burbank, CA, sugar is a carb, virtually indistinguishable from any other type of carb. "Your body processes them exactly the same way," she states emphatically. "They deliver the same number of calories -- four calories per gram."

Frechman goes on to say that breaking sugar out from rank and file "other carbs" makes no sense whatsoever, especially if you do not factor in the added nutritional value of vitamins, minerals and fiber. Cruise in fact does the opposite: He specifically recommends Cheez-Its as a food with an ideal S/C ratio and therefore a good choice for someone on the Belly Fat Cure Diet, despite the fact that a one-ounce serving packs a hefty 180 calories, more than 2 grams of artery clogging saturated fat, and virtually zero in the way of nutrition.

Next, is the concept that eating too much sugar causes an imbalance of the leptin, a hormone which has been linked to increased appetite and fat storage. Frechman spent several years as a scientific nutritional investigator studying, among other things, leptin. She notes that the majority of leptin studies have been performed on rats so the results cannot automatically transfer to humans. "To make these sorts of claims is misleading," she says. "Much of the direct examination done with people has been inconclusive and we're a long way off from completely understanding what role leptin plays in weight gain."

And even if we make the assumption that leptin is indeed the cause of belly fat, Frechman points out that the diet won't necessarily trim your spare tire. "You may lose weight if you wind up eating fewer calories but there is no guarantee it will come off the belly," she says. "There is simply no way to selectively lose fat from a targeted area."

So is paying attention to the amount of sugar and carb servings you eat a good way to stay healthy and lose weight? This one is fiction. The Belly Fat Cure is nothing more than a convoluted and silly version of a low-carb diet. Save the money you would spend on this book and treat yourself to some fresh fruit or a salad.

Many thanks to fitness pro and exercisetv star Jennifer Galardi for bringing this topic to my attention. Now, I would love to hear your opinion. Because he is such a lovely and personable guy – and maybe a few people did lose weight with this method -- I bet Mr. Cruise has a lot of supporters. Or maybe you've tried the diet and found that eating chocolate and Cheez-Its doesn't lead to weight loss after all.