Please forgive me for dispensing with the standard buildup of suspense that you're probably accustomed to when reading articles. But I think that the answer to the question in the headline is an unequivocal "no." It's not too late at all to buy Livongo Health (NASDAQ:LVGO) stock.

Sure, Livongo's share price has more than quadrupled so far this year. That's a huge move in a short period of time. It might seem inevitable that the momentum will fizzle out. However, I think there's plenty of fuel in the tank for Livongo. Here are three reasons why this growth stock has a lot more growing to do.

Woman with palms facing up. An hourglass is above one hand and a stack of cash is above the other hand.

Image source: Getty Images.

1. COVID-19 eye-opener

Livongo Health CEO Zane Burke stated in the company's first-quarter conference call in May, "We believe the COVID-19 pandemic has only reinforced the value of the service we provide our members and clients." There are plenty of reasons to agree with Burke's comments.

For one thing, in the early months of the coronavirus outbreak in the U.S., the Centers for Disease Control and Prevention reported that 78% of ICU admissions related to COVID-19 were for people with preexisting or chronic conditions. This served as an eye-opener for payers, including large employers, health plans, and government programs, about the need to effectively monitor individuals with chronic conditions that put them at high risk.

You can also simply look at Livongo Health's stock chart prior to the COVID-19 pandemic and afterward. All of the stock's gains since its initial public offering on July 25, 2019, have come since April 2020.

To be sure, the COVID-19 pandemic only accelerated a business trend that was already well under way for Livongo. However, the genie is now out of the bottle and isn't likely to back in. There's a greater awareness of the need for solutions like Livongo's digital health-management platform than ever before thanks to the pandemic.

2. An enormous untapped diabetes market

From its beginning, Livongo has primarily focused on helping individuals manage diabetes. It was and still is a winning strategy for the company. And the good news is that there's still an enormous untapped diabetes market to target

As of March 31, 2020, Livongo had around 328,000 members on its diabetes platform. That number will almost certainly be a good bit higher when the company reports its Q2 results on Aug. 6. Even if Livongo's membership swells considerably, though, the company will likely only be scratching the surface of the potential market.

There are currently an estimated 34 million people in the U.S. with diabetes, according to the American Diabetes Association. An additional 1.5 million people are diagnosed with diabetes each year. Livongo could double its current membership and still claim less than 2% of the addressable market. 

3. Multiple expansion opportunities

We haven't even touched on the other chronic conditions that Livongo Health targets. There are more Americans with hypertension than there are with diabetes. Granted, Livongo doesn't think it will make as much money per individual in the hypertension indication as it does with diabetes. Still, though, hypertension presents another $18.5 billion potential market for the company. 

The company also hopes to expand its market by offering solutions for individuals with pre-diabetes and behavioral health. And it's making substantial progress. Large healthcare system Kaiser Permanente selected Livongo's behavioral health platform to offer to all of its members. The contract will roll out over the next five years and could be a significant springboard for Livongo. 

Also, all of the opportunities mentioned thus far focus on the U.S. market only. Livongo hasn't taken any steps to expand into international markets at this point. But there are certainly many individuals with chronic conditions in other countries that could benefit from Livongo's technology down the road.

Focus on the growth

You could look at Livongo Health's valuation (shares trade at close to 51 times sales) and think this is a ridiculously expensive stock that's best to avoid. However, valuation metrics based on historical sales and earnings totally miss the point about Livongo's tremendous growth prospects. It's probably going to be quite a while before it's too late to buy Livongo Health stock.