"I try to invest in businesses that are so wonderful that an idiot can run them. Because sooner or later, one will."

That Warren Buffett quote highlights the importance of investing in a business with solid fundamentals. By doing so, you don't have to worry as much about who is running the company, because it's likely to succeed regardless of who's in charge. It's not a guarantee, but it can significantly reduce your risk.

A couple of stocks I would classify as low-risk, no-brainer investments that I think Buffett would like include UnitedHealth Group (UNH -1.41%) and Anheuser-Busch InBev (BUD -1.60%). Their fundamentals are strong, and these companies can take advantage of long-term trends within their respective industries.

1. UnitedHealth Group

A great example of a no-brainer investment is health insurance. And a leading company in that space is UnitedHealth Group.

Having adequate healthcare coverage is an ongoing need, and demand is likely going to rise, not fall, over the years. A big part of the reason for that is that there will be more seniors. According to projections from the U.S. Census Bureau, by 2060, there will be 94.7 million Americans who are 65 years of age or older, accounting for 23% of the population (versus 17% in 2020).

Due to its massive size (UnitedHealth Group served 151 million individuals last year), the company has significant power in being able to adjust its rates as prices increase, should it need to do so. In the long run, the company targets annual earnings growth between 13% and 16%. Last year, the company's net earnings totaled $20.6 billion and were up 16% year over year. 

For long-term investors, UnitedHealth can make for a solid buy as the business is only going to get bigger over time. The company also pays a modest yield of 1.3% that has been growing over the years.

2. Anheuser-Busch InBev

Another no-brainer investment worth considering is alcohol. In good times or bad, there's generally strong demand for beer. And according to Grand View Research, the global alcoholic drinks market will grow at a compound annual growth rate of 10.3% between now and 2028.

Anheuser-Busch InBev is a leading company in that industry that can take advantage of those growth opportunities. It has many top brands in its portfolio, including Budweiser, Bud Light, and Stella Artois.

When the company last reported earnings in October, Anheuser-Busch InBev reported revenue of $15.1 billion for the period ending Sept. 30, which was 12.1% higher than in the prior-year period. Its Beyond Beer business, which includes hard seltzers, canned wines, and other innovative products that look to tap into emerging consumer trends, generated 10% growth. The company's overall earnings during the period totaled $1.4 billion, which was more than 9% of revenue.

Anheuser-Busch InBev isn't done growing, and between its strong history that goes back 160-plus years, more than 100 brands in its portfolio, and some solid financials, this is a stock that has great potential in the long run. Although its high debt levels have made investors bearish on it in the past, the company has been bringing its debt down over the years. And at a forward price-to-earnings multiple of 18 (which is in line with the S&P 500 average), the stock is well-priced and makes for a good buy right now.