I lost track of how many times Josh Stevens used the word "kale."

Mr. Stevens is CEO of a San Francisco-based Internet startup called Keas. Founded by former Google executive Adam Bosworth and backed by $20 million in venture capital, Keas provides online employee health solutions.

I didn't call Mr. Stevens, a former AOL executive, to hear about kale.

I called to hear him rag about the CVS Caremark drug store chain and other big companies forcing employees to take medical screenings. The corporate machine wants their weight, blood-sugar levels, cholesterol counts, and other formally personal bits of information, or it is going to charge them $600 more a year for health care insurance.

As we talked about this heavy-handed corporate approach, Mr. Stevens repeatedly referenced kale.

I am sick of hearing about kale. It belongs to the same family of vegetables that my peasant European ancestors ate: cabbage, collards and rutabagas. Kale, I have read, was the most common green in Europe until the end of the Middle Ages.

During World War II, the "Dig for Victory" campaign in the United Kingdom championed its cultivation. It was easy to grow and could provide nutrients that went missing due to rationing. Kale, you see, was what there was to eat while the Nazis dropped bombs on people.

Now, suddenly, it's a "super food." Now, I've got CEOs telling me to eat it. Actress Gwyneth Paltrow champions it in her cookbooks. Celebrity chefs and nutritionists claim it lowers cholesterol, prevents cancer, and decreases the absorption of dietary fat.

My wife drags me to chic-chic restaurants where they don't serve Budweiser, but they do serve plates of steamed and seasoned kale.

"Dude," Mr. Stevens continued. (Yes, in hour-long interviews with CEOs, I sometimes get them on the "dude" level.) "Do you know how nutrient-dense kale is?"

Earlier this year, I interviewed Whole Foods CEO John Mackey and he went on and on about kale, too.

"I'm from New York," Mr. Stevens continued. "I'm hardly the West Coast, Birkenstock-wearing, communist-flag-flying liberal, but I will say, kale is the way to go."

Then he started sharing his manly kale recipes. His wife makes kale chips. She sticks kale in the oven at 350 degrees for about 15 minutes. He eats them instead of potato chips while he's watching the game.

"Boom! You've done your greens for the day," he cheered. "You're good to go!"

Mr. Stevens is running a company he describes as "Facebook for your health." His customers are companies with 1,000 or more employees that want to engage their workers in better health choices in hopes of bringing down health-care costs and improving productivity. His product is a program that works much like a social network and a social gaming platform. It puts employees on teams where they support each other on health-related goals. Along the way, they can earn rewards such as the elimination of health-care deductibles. If you're in this program, you can earn points when you a post a photo of your lunch and it is kale.

Mr. Bosworth, who founded Keas and brought on Mr. Stevens as CEO, had previously developed Google Health. Mr. Bosworth left Google in 2007 before the launch of Google Health. Google shut it down in January 2012 after it failed to attract enough users. Keas aims to be more engaging, and it has competitors with similar approaches, including RallyOn, Hubbub Health, ShapeUp and Global Corporate Challenge.

"What CVS is trying to do is what we see a lot of large corporates doing, which is auditing their population," Mr. Stevens said. "It's their team. They get to understand who they've got and what they've got."

A recent survey by human resources outsourcing company Aon Hewitt found that nearly 60% of companies, like CVS, plan "to impose consequences on employees who do not take appropriate action for improving their health."

Critics see this as a big, corporate scheme to weed out weaker employees. CVS says it won't see the health data it collects. The program is designed to lower health-care costs, not to shape decisions about employment, the company says.

"What's the difference?" said Mr. Stevens. "Most large corporates are both insuring and looking for performance."

There's no other point to a cholesterol check if there's no program to encourage employees to lose weight or lower their cholesterol, Mr. Stevens said. Americans have been getting similar screenings from life insurance companies for decades and now we have a full-blown obesity crisis.

He at least got me thinking: If companies like CVS can bleed their employees in laboratories and coerce them into coughing up numbers, they might also be able to force-feed them kale.

"Kale is the green of choice," Mr. Stevens said. "It's all about kale, dude."