Forward Chris Wood, midfielder Bruno Guimaraes and defenders Kieran Trippier, Dan Burn and Matt Targett all arrived at St James’ Park last month to bolster the team, who sit second from bottom of the English top-flight.
Newcastle boss Howe said he was pleased with his business in the first transfer window since the Saudi-led takeover of the club in October.
“I think we definitely end the window stronger as a team, as a squad,” he said at his press conference on the eve of Tuesday’s home match against Everton.
“Signing five players seems a lot on the surface but I think we’ve been able to drip-feed players into the team, not have to do it all at once,” he added.
Trippier and Wood have already featured in Premier League matches against Watford and Leeds and all five of the new signings could be involved against Everton.
“It feels like we’ve strengthened the group, we haven’t destabilised the team, which can be a very dangerous thing when you’re bringing five in at once,” said Howe.
But the Newcastle manager said the proof would be on the pitch.
“Nothing is done on paper,” he said. “The additions we’ve made I really like. I really like the players we’ve brought in. I think they’ve got outstanding individual qualities but also I think the most important thing with every player we’ve signed is they’re very good people. They’ve got a winning mentality. I think they are leaders in their own right.”
Howe batted away suggestions he was under increased pressure as a result of his big spending in the transfer window.
“I’m under no illusions as the manager of this huge club but I’m always going to be in the firing line,” he said.
Howe also revealed that forward Callum Wilson faces a battle to be fit before the end of the season.
Wilson, who has scored six goals during the current campaign, was expected to be sidelined for around eight weeks after suffering a calf injury during the 1-1 draw with Manchester United on December 27.
However, Howe admitted the striker might be missing for significantly longer, saying he was making “slow progress”.
“I don’t think it’s going to be short-term,” he said. “Hopefully he can make the last few games of the season and really help us in the key moment.”
Wilson’s lengthy absence is a big blow to the Magpies, who invested £25 million ($34 million) last month in Burnley forward Wood, but failed in their attempts to further boost their firepower as their pursuit of Manchester United’s Jesse Lingard and Reims’ Hugo Ekitike came to nothing.