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You’ve tried the Atkins diet, the South Beach diet, and the diet-of-the-week on cable TV. Nothing seems to work. What if you could lose that excess fat by simply inhaling and then exhaling your fat in the form of carbon dioxide?

In a study published in Cell Metabolism, chemical and biomolecular engineering professor James Liao, associate professor of human genetics and pediatrics Katrina Dipple, and their research team at UCLA showed that genetic alterations enable mice to convert fat into carbon dioxide and remain lean while eating the equivalent of a fast-food diet.

Oh sure, those TV ads don’t make it any easier. Most of us non-vegans see a juicy burger and fries during a commercial break and we’re ready to jump in the car and head to the nearest Burger King or McDonald’s. Even President Obama manages to sneak out — if you can call a trip to the local burger joint with full Secret Service entourage “sneaking” — for the occasional cheeseburger with jalapeño, lettuce, mustard and tomato.

For fast food junkies and the poor, eating burgers and fries every day can mean an ever-expanding waistline and associated health problems such as diabetes. Morgan Spurlock’s hard-hitting 2004 documentary, Super Size Me, describes the effects of a 30-day McDonald’s-only diet — a fit then-32-year-old Spurlock gained 24½ lbs and experienced sexual dysfunction and liver damage.

Rather than another diet-of-the-week or guilt-laden trip to your favorite fast-food joint for a burger and fries, the new UCLA study provides a completely new way to approach the problem. It represents the work of the Henry Samueli School of Engineering and Applied Science, in collaboration with the David Geffen School of Medicine.

“We came up with an unconventional idea which we borrowed from plants and bacteria,” said Jason Dean, a graduate student on professor Liao’s team and an author of the study. “We know plants and bacteria digest fats differently from humans, from mammals. Plant seeds usually store a lot of fat. When they germinate, they convert the fat to sugar to grow. The reason they can digest fat this way is because they have a set of enzymes that's uniquely present in plants and bacteria. These enzymes are called the ‘glyoxylate shunt’ and are missing in mammals.”

The glyoxylate shunt is composed of two enzymes. MIT Technology Review reports that the researchers introduced genes for these enzymes from E. coli bacteria into cultured human cells and found that they increased the metabolism of fats in the cells. Rather than converting the fat into sugar as bacteria do, the cells converted the fat completely into carbon dioxide.

Professor Liao’s team analyzed gene expression in the cells and found that the new biochemical pathway promoted cellular responses that led the cells to metabolize fats rather than sugar.

The research team then introduced the genes into the livers of mice. While normal mice gain weight when put on a high-fat diet, professor Liao says that the engineered mice “remained skinny despite the fact that they ate about the same and produced the same waste” and were as active as their normal counterparts. They also had lower fat levels in the liver and lower cholesterol levels.

As with the cultured human cells, the engineered mice did not convert the fat into sugar, which could have the dangerous side effect of promoting high blood sugar and diabetes. Instead, the researchers found a measured increase in carbon dioxide output — the excess fat was literally released into thin air.

The mice exhibited no visible side effects, although more detailed studies are necessary to verify that.

“One exciting aspect of this study is that it provides a proof-of-principle for how engineering a specific metabolic pathway in the liver can affect the whole body adiposity and response to a high-fat diet,” says Karen Reue, a UCLA professor of human genetics and a contributor to the study. “This could have relevance in understanding, and potentially treating, human obesity and associated diseases, such as diabetes and heart disease.”

Here’s an important caveat: there’s no substitute for eating well-balanced meals and exercising every day if you want to try to stick around for the Singularity. Ray Kurzweil recommends taking vitamins and eating a diet that is low in carbohydrates, fat and dairy products and high in vegetables for encouraging longevity.

I wouldn’t expect to see an “Inhale-Exhale diet” soon on cable TV, or featured on the website of Dr. Andrew Weil, MD. However, genetic alteration using the glyoxylate shunt may one day offer a solution to the major medical problems, early death, and rising health care costs associated with obesity.