As you build your portfolio over time, it's good to diversify your investments into a wide range of stocks and sectors. Be sure they align with your overall goals and risk tolerance -- and that they can help you work toward the returns you desire.

The healthcare industry is full of compelling businesses that are often at the forefront of medicine, developing cutting-edge treatments, medical devices, and other products that are changing the face of healthcare while serving a broad and growing market.

While healthcare businesses are not wholly impervious to downturns, they tend to be less vulnerable to tough economic conditions as a result of their essential nature. Consumers need medical care no matter what is happening with the economy.

Here are two such healthcare stocks that could add considerable juice to your portfolio in the years to come.

1. Vertex Pharmaceuticals

Vertex Pharmaceuticals (VRTX 2.86%) has built a successful business around a relatively small set of highly successful drugs. All of them treat cystic fibrosis and bear the distinction of being the only treatments approved and commercialized to date that actually target the underlying cause of this genetic disease.

While all of its treatments have been clear commercial successes, the product that currently accounts for the lion's share of Vertex's revenue and profits is the triple-drug cocktail Trikafta. At the time of its approval in 2019, Trikafta was indicated for roughly 90% of the cystic fibrosis patient population in the U.S.

Considering that patent exclusivity on this treatment won't lapse until the latter half of the 2030s, there's considerable ongoing profit potential for Vertex as expanded approvals -- and the reality that its drugs are helping patients live better and longer -- are widening its total addressable market.

Vertex is working on other cystic fibrosis treatments. These include a different triple-combination therapy that it intends to seek approval for later this year, as well as an mRNA-based drug it is developing with Moderna designed specifically for patients whose variant of the disease is not treatable with its existing medicines.

That latter candidate has a potential addressable market that represents thousands of cystic fibrosis patients who are currently in need of a therapy to address their particular mutation and have virtually no treatment options.

Vertex is looking well beyond the cystic fibrosis treatment market for future growth. It just garnered approval for Casgevy in several markets, including the U.S. Casgevy is the gene-editing therapy it developed with CRISPR Therapeutics, and is designed to be a one-dose functional cure for patients with sickle cell disease or transfusion-dependent beta-thalassemia.

Initial approvals for patients with severe versions of those conditions would cover around 35,000 patients just in the U.S. and Europe, but considering there are about 100,000 individuals domestically and 20 million individuals worldwide in the sickle cell disease patient population alone, there is a significant growth opportunity here.

Long-term investors may want to consider a position in this healthcare stock sooner than later.

2. Intuitive Surgical

Intuitive Surgical (ISRG 3.19%) has a chokehold on the surgical robotics market, a reality it demonstrated again with its stunning results from 2023. It has been a tough few years for the business in some ways, particularly given changes in hospital spending due to the ongoing macroeconomic environment and fluctuations in procedure volumes in key markets.

However, the company has remained profitable, steadily growing its revenue, and maintaining a solid market share. Considering that Intuitive Surgical controlled a roughly 80% share of the global surgical robotics market as of 2021 -- a space that is growing as adoption of these tools in both non-invasive and open surgeries expands -- there's still a lot of room for the business to flourish over the next decade and well beyond.

In 2023, Intuitive Surgical brought in record profits as procedure volumes recovered and its installed base of surgical systems expanded. Revenue totaled $7.1 billion, a roughly 15% increase from 2022, while net income came in at $1.8 billion, a whopping 35% jump from the prior year.

Intuitive reported a 21% year-over-year increase in worldwide procedures using its flagship da Vinci systems in the final quarter of 2023. The company also ended the year with 14% more da Vinci systems installed globally than at the end of 2022. Intuitive Surgical reported $7.3 billion in cash and investments on hand at the end of the year, while trailing-12-month operating cash flow totaled $1.8 billion.

If you're looking for a solid healthcare business with a wide moat and a profitable portfolio of products that face a vast and growing total addressable market, Intuitive Surgical meets the mark on all counts.