"The average American doesn't have the geographical knowledge the average New Zealander has," the 42-year-old says from his home in Santa Monica.
"We're isolated so we look outwards a lot and understand we are a small country and don't see ourselves as the centre of the world.
"In America, there are a lot of people who simply don't learn basic geography.
They wouldn't know where Great Britain is or Italy - actually, they probably know Italy, but only because it looks like a boot."
Keoghan's show, a prime-time reality programme in the United States where teams of two compete in a race around the world, has done its bit to help change that over 15 seasons.
"For them to be able to see Muslim people showing kindness to strangers is the only time they see other cultures.
Really, some Americans have a conception that everyone in a turban is a terrorist."
Keoghan also boasts that The Amazing Race has had an amazing diversity of people take part.
Racers have included openly gay couples, a deaf boy, a small person and a lesbian priest.
"We have people with bung knees and pot bellies, ordinary people like the people we know in our own lives."
Keoghan had to learn to put on an American accent to get the Amazing Race role, he says, because network television audiences are so huge in the US.
The show is regularly watched by more than 10 million people so programmers will not risk putting someone on screen who might turn viewers off or be hard to understand.
That attitude is changing somewhat - American Idol judge Simon Cowell is on screen with an English accent - but Keoghan says on prime time television the competition is fierce.
No-one can say Keoghan doesn't do his bit as an unofficial New Zealand ambassador.
He has brought the show to New Zealand three times, most recently including his father in the programme.
There are lots of New Zealand references in Keoghan's conversation: his speech to his old school of St Andrews, conversations with the Canterbury Tourism Board about promoting his home province, his 12 trips home last year.
"Part of it is that people have contacted me, but part of it is my genuine love of the country."
The Amazing Race only makes up about a quarter of his work, which includes speaking engagements and promoting his book, No Opportunity Wasted.
He estimates he flew 650,000km last year.
He is talking to various New Zealand companies about marketing opportunities and how he could help promote their products overseas.
Keoghan seems to have a never-ending amount of energy and determination.
"I'm stubborn when I believe in something", he says.
"I just persevere." - Deborah Hillcone
