Healthcare is a great industry to invest in because it can offer a lot of stability when economic challenges weigh down stocks in other industries. Medical innovation is always in demand and people will always need prescriptions, medical devices, and health services no matter the state of the economy.

Healthcare stocks are great pillars to build a portfolio around, and for investors who are looking to add some well-valued stocks for 2020, it's hard to go wrong with any of these three promising companies.

1. Jazz Pharmaceuticals

Jazz Pharmaceuticals (NASDAQ:JAZZ) is a global pharmaceutical company with a broad and diverse product mix in its portfolio. Its flagship product, Xyrem, offers relief to people with narcolepsy, and over the past three quarters, it accounted for 76% to 80% of the company's total product sales. Although Xyrem is a big part of Jazz's business today, the company is also working on many other products.

Earlier this year, the U.S. Food and Drug Administration approved the company's drug Sunosi, which helps patients who have trouble staying awake during the day, a symptom of narcolepsy and obstructive sleep apnea. It launched in the U.S. in July, and it's anticipated that it will get the OK from the European Union to commence sales there sometime next year. 

The Ireland-based company has several drugs focusing on hematology and oncology that are in either the second or third phases of testing and that could become available in the near future. This includes Defitelio, a drug that treats veno-occlusive disease which is the blockage of blood vessels leading to the liver, as well as Vyxeos, which treats acute myeloid leukemia -- a type of cancer. Both drugs are currently in phase three.

Prescription medication.

Image Source: Getty Images.

Jazz focuses on finding solutions for rare or complex diseases. This allows the company to fill an important void in the healthcare industry for patients struggling with conditions overlooked by other drug manufacturers, which could open up many growth opportunities for the company in the future.

The company has done a good job thus far of growing its business while also increasing its bottom line. Jazz's sales grew by 43% from 2015 to 2018, and profits rose by 36% during that time. During the trailing twelve months, the company recorded a net income of $609 million on revenue of $2.06 billion, averaging a very strong profit margin of 30%. And with the stock trading at just 14 times its book value, it could be a solid buy for both value and growth-oriented investors. 

Jazz's stock has risen 19% year to date, which underperformed the broader market which grew more than 25%, but 2020 could see several catalysts for Jazz that allow it to start outperforming the healthcare sector and the U.S. market.

2. Bristol-Myers Squibb

Bristol-Myers Squibb (NYSE:BMY) is a more notable name in the industry, with a whopping $150 billion market cap. It offers investors a lot of stability, as this low-volatility stock produced nice returns of 21% in 2019, which still underperformed the S&P 500 for the year but demonstrated an ability to grow.

The company has an even more diverse set of products than Jazz, including treatments for cancer, diabetes, hepatitis, and HIV/AIDS. Although Bristol-Myers hasn't seen much growth in recent years, with its revenue rising from just $19.4 billion in 2016 to $22.6 billion in 2018, there's plenty of potential ahead for the company with its acquisition of Celgene complete. 

Celgene has many more products progressing through the testing phases that provide Bristol-Myers with additional growth opportunities. Opdivo, which treats advanced-stage cancers such as lung, kidney, and liver, in addition to other cancers, is one example of a drug that's exciting investors. Eliquis treats blood clots and is another drug that can be critical to Bristol-Myers' long-term growth. According to estimates from 2018, both drugs are projected to be among the top five drugs in 2024.

Bristol-Myers averaged strong gross margins of at least 70% in recent years, making it no wonder that the company hasn't had a problem turning a profit. In 2018, Bristol-Myers' profit of $5 billion was 22% of its top line. 

It's another good value stock for investors to consider, trading at a modest 18 times earnings. As an added bonus, the stock also pays a dividend of 2.8% per year. Overall, Bristol-Myers gives investors a little bit of everything.

3. HCA Healthcare

HCA Healthcare (NYSE:HCA) doesn't develop or make drugs, but it operates 185 hospitals and 119 surgery centers across 21 states and the U.K., serving 28 million patients every year. It's a more stable and consistent business than what investors might otherwise get with a drug manufacturer that's dependent on clinical trials. The downside is HCA's growth opportunities are more limited.

Sales of $46.7 billion in 2018 rose just 18% since 2015 when HCA's top line was $39.7 billion. That averages out to an annual growth rate of 5.6%,  which translates into very stable profits. In each of the past three years, the company's operating income was more than $6 billion.

HCA's stock climbed 18% in 2019, which is less growth than the broader market enjoyed, but it's a very cheap buy today. Trading at a multiple of just one times its sales and 14 times earnings, HCA is another top healthcare stock that provides investors a lot of bang for their buck. The company also offers investors a modest dividend of 1.1%, lower than the average dividend of the S&P 500 at 1.85%. 

Picking between the three stocks

For investors who value stability, HCA offers the most predictable results moving forward, given that its business isn't dependent on drug approval. Jazz Pharmaceuticals and its market cap of $8.4 billion is the smallest stock on this list, meaning it has the potential to provide the greatest returns with a PEG ratio of 0.86, suggesting it's a good deal for its growth potential. Bristol-Myers has a PEG around one and it could provide the best mix of value and growth for investors.

However, all three healthcare stocks could be great buys today for investors.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.