"I had tried so many other things that were not so successful for me: Weight Watchers, exercise, making myself a promise that I'm going to eat right," she said. A mental switch finally flipped when Jeffries's DNA test indicated she had some genetic predisposition to being overweight. "It wasn't all me that was the problem," she said.

Employers have poured money into wellness programs, hoping to reduce health insurance costs, but employees have been less enthusiastic.

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More than two-thirds of organizations have some sort of health or fitness offering, from health screening assessments to in-office exercise classes. Companies spent a record $693 per head on wellness initiatives last year, up from $594 the year before.

For all that effort, Gallup's research put participation rates in wellness programs, an umbrella term for a variety of employer-sponsored health initiatives, at just 24 percent in 2014.

When it comes to disease management programs that help people with chronic conditions, like diabetes, and have the greatest financial impact, participation is even lower, around 10 percent to 20 percent, research has found.

Newtopia, which costs $500 per head, has had encouraging results at Aetna. Of 445 employees who enrolled in the program as part of a three-year study published in the Journal of Occupational and Environmental Medicine in December, about 50 percent remained "engaged" a year later, according to Aetna.

More than three-quarters of participants lost an average of 10 pounds. Newtopia did another pilot at Jackson Laboratory and saw similar results.

Many wellness programs use financial incentives, like a discount on health insurance premiums, to motivate employees to participate. That can work, but people tend to do the minimum amount of work to avoid a penalty or get the reward.

Newtopia's participants cited the genetic testing component as a big motivator. "We had individuals that said having the knowledge of their own individual profile allowed them to gain a certain understanding and mastery of their condition that they didn't have before," said Aetna's Dr. Greg Steinberg, who ran the Newtopia pilot program. Off the success of the pilots, Newtopia has signed up eight employers.

Newtopia is geared to get results that will help companies save the most.

The program specifically targets employees at high risk of developing metabolic syndrome, a group of risk factors that raise a person's risk of heart disease, diabetes, stroke, and other health problems that can hurt an employer's bottom line.

Costs jump by hundreds of dollars per month when an employee has metabolic syndrome, actuarial analyses have found. Newtopia is only available to those with at least two risk factors for metabolic syndrome, such as a large waist circumference, high blood pressure, or high glucose levels.

For those who fit the profile, Newtopia offers what it calls "bespoke" wellness. Qualifying employees get an activity tracker and an "inspirator," a coach matched with the participant based on personality. "Think EHarmony," said Jeff Ruby, chief executive of Newtopia.

A genetic testing kit comes in the mail. It tests for three "susceptibility genes related to obesity," explains Dr. Louis Perusse, Newtopia's in-house geneticist. There's a so-called "fat" gene, as well as a gene that regulates appetites, and a gene that shows eating triggers some people's dopamine receptor—which suggests they get pleasure from eating.

The results aren't used as a diagnostic tool. "There's not a clinical element to it," said Ruby. "It's all about engagement." The test helps the inspirator craft a diet and exercise plan. Someone with the "fat" gene might do high- intensity exercise, for example.

More important, the results can serve as a mental aid. "It [genetic testing] allows them to stop blaming themselves," said Ruby. "This is one area that they haven't been able to figure out for many years. They build up shame, blame, lack of self-esteem and confidence. [DNA testing] allows them to open up to change by connecting that 'aha' moment with a sense of control."

George Annas, a bioethics professor at Boston University, cautions against reading too much into DNA tests. "The chance that they have a genetic test that can determine if you're prone to be fatter than other people is very, very unlikely," he said. "What [Newtopia] really seem to be saying is that if you tell people that you have a genetic condition that may predispose you to be overweight, that may motivate people."

For some, he said, DNA testing could have the opposite effect: If someone is predisposed to gaining weight, then why bother dieting or exercising?

Newtopia was very careful not to characterize its genetic testing as anything more than a guide.

And as for potential privacy concerns, Newtopia says it doesn't share any individual data with employers.

For some, like Jeffries, knowing that genetics has something to do with her weight helped change her attitude toward weight loss. "When I really just looked at it, and said OK, I was overweight, I have been the majority of my life. If the gene is already present, that's the dormant factor. I didn't need food to be overweight," she said. "When I dropped those 10 pounds, it wasn't painstakingly hard."

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