Are You Genetically Predisposed to Be Skinny?

Credit: Arthur Belebeau/Trunk Archive

It isn't every day that the first words out of my mouth are "No, thanks--I need to keep my saliva pristine." But for once, coffee wasn't the first thing on my mind when the alarm wailed and my husband rolled out the door to Starbucks. This morning I was going to test my fitness genes with a home DNA kit, and I wasn't supposed to eat or drink anything for 30 minutes before taking it lest I contaminate my specimen--a scenario comically laid out by FitnessGenes CEO Dan Reardon when I called him yesterday to inquire about protocol. "Let's say you ate a bacon sandwich and some of that got left behind," he said in a clipped British accent. "There's a potential ... well, it could look like you have pig DNA. There was one person who sent about five samples to us. Every time my team analyzed the cells, they were like, 'Dan, I'm sure this isn't human DNA.'"

Today, as it is most days, my goal was to pass as human (no small task without my usual three cups of caffeine). The test--which would analyze more than 40 genetic variations related to fitness and nutrition using just a tiny specimen of cheek cells--promised to explain some of the greater mysteries of my ongoing love-hate relationship with exercise and food (and, hopefully, help fine-tune a regimen that would put an end to my newly acquired muffin top). "What the genetic information really tells us is your response to training," explained Reardon, debunking the notion that certain genes translate directly into athletic prowess. "If, for example, the test shows you have a gene associated with endurance, it means you will benefit from that kind of training."

Having recently put on a few pounds, I didn't need a hard sell. With two kids at home, a full-time job, and a new, longer commute that made it nearly impossible to exercise before work, I needed some fresh strategies--the more efficient, the better. And so it was that I found myself hunched over a plastic funnel at 7 a.m. on a Monday, swapping my saliva for a bit of hope.

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Three weeks later, I received an email that my results were in. The report was dense, covering everything from my genetic propensity for speed and endurance (fun fact: I carry a strength/power gene that has been found in almost every single Olympic 100-meter runner ever tested) to my ability to process caffeine (no surprise here: I'm a fast metabolizer). The test confirmed a lot of what I already knew (I'm an early riser and have two genes for blue eyes) or suspected from years of trial and error (when I eat saturated fat, it goes straight to my ass). The most disturbing revelation? Apparently, I carry two copies of the FTO "obesity gene." Thanks, Mom and Dad.

The more I read about how the FTO variant worked, the more I cringed with recognition. "Carriers of a particular version of the gene are biologically wired to eat more and feel hungrier sooner," the report explained. My mind flitted back to lunch: While my friend had gingerly sipped a small bowl of pea soup, I tore through my own soup, plus chicken and brussels sprouts. Then I ate her crackers. And then I went back for more crackers. "In ancient times, this gene may have been a straightforward survival mechanism," I read from my report. "But it becomes problematic in a modern world with easy access to high-energy foods." I laughed. Though I had invested a considerable amount of time in my adult life learning the calorie counts and nutritional breakdowns of different foods, I now find myself sitting all day at a desk, 5 feet away from a giveaway table routinely stocked with rainbow-colored Rice Krispies treats, Sprinkles cupcakes, and cookies iced in the likeness of Iris Apfel. It is a high-carb, sugar-laden jungle out there.

Concerned, I called Clifford Rosen, a geneticist who conducted some of the seminal research on the FTO gene. Interestingly, the key study he did involved a different variant of the gene that had to do with fat storage, not appetite. Still, he wasn't convinced I should be alarmed. "There are so many variants in every genetic sequence that it's almost impossible to make a prediction with this little information," he told me. "The era of personalized medicine is definitely upon us, but the science for this is just not there yet."

Is it possible that my genetic report was like some sort of sci-fi horoscope, riddled with enough germs of semi-plausible truth that anyone could see herself in it? When I shared the report with Equinox Tier X trainer Matt Delaney, he also expressed skepticism. "Your genes are one piece of a multifaceted puzzle, and their expression is in no way absolute. They are about tendency, not inevitability, and should be looked at as such." He says Equinox did a pilot program with genetic testing but moved away from it because the trainers felt the data was "not actionable" and that coaching based on tendencies was unrealistic.

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To be fair, Reardon himself never claimed that genes were destiny. In fact, the FitnessGenes kit seems designed to prove the opposite: that genetic potential can be manipulated and/or maximized with the right knowledge. To that end, each report comes with detailed workouts and nutritional advice based on your unique genetic profile and personal goals. My exercise plan included a mix of resistance, cardio, and high-intensity training (so I wouldn't plateau). The nutritional guidelines happily contradicted virtually every bit of hard-core diet gospel I'd been given for the past 10 years: "Eat carbs," advised Reardon. "People with this version of the FTO gene can't eliminate them because you won't be satisfied so you will end up eating more." He did, however, advise me to limit my consumption of fat (yes, even the healthy kind). "People with your profile do better on a low-fat, high-protein diet with some carbs." To curb my appetite, I was told to eat five small, protein-packed meals throughout the day and avoid any rogue snacking with glutamine .

Six weeks into my genetic experiment, I am happy to report that I no longer look like I'm carrying a food baby. My legs are toned, my muffin top is trimmed. I'm not working out more, I'm just working out better. The best part? I'm eating pasta again (and I don't mean the spiralized-zucchini kind). And for that, I'd happily spit in a funnel all day.

GENETIC WEAPONS

The Monitor

Credit: Time Inc. Digital Studio

Didn't inherit the early-bird sleep gene? This superchic wearable can help you track your steps--and your z's.

Access Crosby Activity Tracker, Michael Kors ($95; michaelkors.com/access)

The Supplement

Credit: Time Inc. Digital Studio

If you crave carbs, try quelling the urge with 1 to 2 grams of glutamine dissolved in water.

Clean Program Integrity ($75; cleanprogram.com)

The Test

Credit: Time Inc. Digital Studio

With this simple saliva test, researchers can analyze more than 40 variations in your DNA that have been linked to physical performance and nutrition.

FitnessGenes DNA Collection Kit ($200; fitnessgenes.com)