Billionaire investor Vinod Khosla explains why he backed HealthifyMe after passing on the AI-powered startup

• Vinod Khosla invested in HealthifyMe after passing on the startup a few years ago.
• The venture capitalist told Insider he was impressed by the health-and-fitness app's use of AI.
• Khosla Ventures co-led HealthifyMe's $75 million funding round in July.

Billionaire investor Vinod Khosla recently backed an Indian health-and-fitness app called HealthifyMe. The Khosla Ventures boss told Insider in an exclusive interview why he plowed millions of dollars into the startup after passing on it only a few years ago.

HealthifyMe combines human coaches with artificial intelligence to provide nutritional advice, fitness classes, and diet-and-exercise plans to around 25 million users. Khosla Ventures was the co-lead investor in HealthifyMe's Series C funding round, which raised $75 million for the company last month. HealthifyMe has now raised over $100 million from investors including Unilever Ventures and Elm - an IT security company owned by Saudi Arabia's Public Investment Fund.

The startup's vast addressable market, coupled with its goal of helping people become healthier and more active, appealed to Khosla. "The larger the problem, the bigger the opportunity," he said. "Obesity and health are large problems."

"Good for society, good for business," he said about HealthifyMe's mission.

Khosla was most excited about the app harnessing AI to offer tailored nutritional advice based on a user's local cuisine and specific health conditions, such as diabetes or hypertension. Without that technology, the company would have to employ an army of nutritionists, making it much less scalable and affordable, he said.

HealthifyMe's use of AI gives it a superior growth trajectory to a typical dieting company, while its app trumps conventional dieting and weight-loss books, because it can update its advice based on the latest scientific research, Khosla added.

The venture capitalist told Insider he seeks to invest in talented founders with grand visions of disrupting large markets. He pointed to Square CEO Jack Dorsey, who started his payments company with the goal of transforming small business. Khosla especially prizes entrepreneurs whose dreams grow as their businesses take off.

"They've kept expanding their vision of how large the market is and what they can do with AI," he said about HealthifyMe.

Khosla told Insider that he met with HealthifyMe cofounder and CEO Tushar Vashist a few years ago, but he didn't believe the entrepreneur would deliver what he promised. "Silly of me," he said.

While the investor didn't get on board the first time, "the boat came back around," he added.

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