"We've seen our forwards make big strides in the last couple of outings," Henry said. "The selectors believe they should have a chance to raise the level of their performance even higher.
"There is nothing separating our top players in some positions. The changes acknowledge the great form of some All Blacks who missed out on selection last week.
"Going forward, the team needs to have more than one player ready for international rugby at every position. It is part of our strategy to develop and maintain that depth."
Injured duo Mose Tuiali'i and Anton Oliver, whose calf injury has ruled him out of the series, were not considered for selection. Tuiali'i is expected to return to full training this week.
There is also concern surrounding prop Carl Hayman who is in hospital receiving antibiotics for an infected toe. Campbell Johnstone is on standby.
New Zealand team to face the British & Irish Lions at the Westpac Stadium, Wellington:
Mils Muliaina; Rico Gear, Tana Umaga (capt), Aaron Mauger, Sitiveni Sivivatu; Dan Carter, Byron Kelleher; Tony Woodcock, Keven Mealamu, Carl Hayman, Chris Jack, Ali Williams, Jerry Collins, Richie McCaw, Rodney So'oialo.
Replacements: Derren Witcombe, Greg Somerville, Jono Gibbes, Sione Lauaki, Justin Marshall, Ma'a Nonu, Leon MacDonald.