With no standout team, Best feels the form of the Irish provinces stands them in good stead for Saturday's opener in Rome.
"We're taking part in this competition to win it, that's first and foremost in our mind," said the 28-year-old, who returns to the side after a rib injury.
"I don't think the number of injuries is a worry.
"Look at the strength of the squad with the injuries. It says a lot for the way we've evolved over the last six years.
"It's probably not a bad thing to test the depth of the squad. We owe a lot to the way the provinces have developed over the last few years."
And although Ireland's only three defeats to Italy all came before their entry into the Six Nations more than a decade ago, Best maintains Italy are not to be taken lightly.
He said: "We're under no illusions, Italy are a very good team. We've seen a lot of them in the Magners League and at Ulster we faced Aironi in Europe.
"If you take any of them lightly, they'll beat you. Leinster lost in Treviso at the start of the Magners League and that shows they have the ability to beat teams.
"They've evolved a lot over the last few years under their coach Nick Mallett."