Inkinen's online real estate information company, Trulia, was sold in 2014 to Zillow for $3.5 billion. So naturally, the next step for Inkinen was to start a new company. He teamed with a doctor and a scientist, Stephen Phinney and Jeff Volek, and founded Virta Health.
Virta connects patients virtually with doctors and coaches who help tailor the ketogenic diet to their lifestyles and monitor certain biomarkers daily.
In a trial of about 260 patients, published last year in JMIR Diabetes, Virta's treatment led to reductions in blood glucose, weight and use of diabetes medication after 10 weeks. After a year A1C levels were down an average of 1.3 percent, diabetes medication usage was down 48 percent, and body weight was down 12 percent.
To cardiologist Ethan Weiss, who sits on Virta's scientific advisory board, the outcomes are strong enough to recommend the program to his patients.
"For people with type 2 diabetes headed toward bariatric surgery, to have this result, that they're coming off almost all insulin, coming down on almost all other diabetes medicines, losing weight, feeling like they control their diet, I think it's an awesome thing to recommend," said Weiss, an associate professor of medicine at the University of California San Francisco.
While most of the metrics move dramatically in the right direction — Inkinen says 60 percent of patients see their diabetes reversed in a span of between two and nine months — Weiss notes one data point that may not. Levels of LDL, or so-called bad cholesterol, appear to rise on the ketogenic diet. But he notes a distinction in the type of LDL that goes up, saying it may not be the type that leads to clogged arteries. And he says LDL levels can be controlled with drugs called statins, like Lipitor, if that's a concern (though he said to him it's not).
Virta's program, which costs $370 a month after a $500 initiation fee if patients pay out of pocket, also saves money, according to Inkinen, who estimates an average savings of $9,600 per patient in the first 24 months in drug and medical costs. After the first year the cost drops to $199 a month.
The company is working to expand to more coverage from insurers and employers, with the goal of reversing diabetes in 100 million people by 2025.
That's about the number of Americans with diabetes or prediabetes, according to the Centers for Disease Control and Prevention.
As usage — and costs — of diabetes medicines rise, both Geisinger and Virta are showing that food, along with a healthy dose of education and support, can go a long way in changing the course of this disease.
— Additional reporting by CNBC Producer Karen Stern
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