I don't know if anyone has already done this, but I compiled this three months ago.
I think the stats are interesting.
Ages from wikipedia:
http://en.wikipedia.org/wiki/List_of_The_Amazing_Race_(U.S._TV_series)_contestantsCombined ages of all TAR winners from oldest combined age to youngest combined age:.
TAR5 -- Chip & Kim, 46 and 44, COMBINED AGE = 90
TAR7 -- Uchenna & Joyce, 40 and 44, COMBINED AGE = 84
TAR4 -- Reichen & Chip, 28 and 36, COMBINED AGE = 64
TAR14 -- Tammy & Victor, 26 and 35, COMBINED AGE = 61
TAR6 -- Freddy & Kendra, 34 and 25, COMBINED AGE = 59
TAR1 -- Rob & Brennan, 27 and 29, COMBINED AGE = 56
TAR10 -- Tyler & James, 29 and 27 , COMBINED AGE = 56
TAR9 -- BJ & Tyler, 26 and 25, COMBINED AGE = 51
TAR11 -- Eric & Danielle, 28 and 23, COMBINED AGE = 51
TAR2 -- Chris & Alex, 25 and 24, COMBINED AGE = 49
TAR3 -- Flo & Zach, 23 and 23, COMBINED AGE = 46
TAR15 -- Meghan & Cheyne, 23 and 23, COMBINED AGE = 46
TAR12 -- TK & Rachel, 22 and 23, COMBINED AGE = 45
TAR13 -- Nick & Starr, 22 and 21, COMBINED AGE = 43
TAR8 -- Linz family, 24 22 21 19, COMBINED AGE = 86
-- TAR1-TAR7 have 5 of the 7 oldest winning teams in TAR history.
-- TAR12-TAR15 have 3 of the 4 youngest winning teams in TAR history.
-- Ten of the winning teams in TAR1-TAR15 have all team members in their twenties or younger.
-- Every winning team in TAR1-TAR15 has either all members in their twenties or younger, all members in their forties, or one member in their twenties and one in their thirties.
-- Out of the six remaining teams in TAR16, there are 2 teams of twenty-year-olds, 2 teams of forty-year-olds, 1 team with a twenty-year-old and a thirty-year-old, and 1 team with a fifty-year-old and a twenty-year-old.