As the Federal Reserve kicks off a long-awaited rate cutting cycle, some investors are wary that richly valued U.S. stocks may have already priced in the benefits of easier monetary policy, making it harder for markets to rise much further.

U.S. stocks rose after the Federal Reserve lowered its benchmark interest rates by 50 basis points to a range of 4.75% to 5%. That was the first rate cut in over four years that marked the beginning of a monetary-easing cycle in the world's largest economy.

Investors’ giddy reaction turned slightly negative to the hotly anticipated Federal Reserve decision to lower interest rates by 50 basis points Wednesday, as the central bank opted for the more stock-friendly route to kick off its rate cutting cycle.