Froome made the statement after the 15th stage of the Tour de France on Sunday, where he finished in the same time as stage winner Andre Greipel to defend his lead in the general classification.
The Team Sky rider's dominance of this year's race has seen allegations and questions raised about whether he has used banned substances.
"Times have changed. Everyone knows that. This isn't the Wild West that it was 10, 15 years ago," Froome said.
"Of course, there are still going to be riders who take risks (with performance-enhancing drugs) in this day and age, but they are the minority. It was the other way round 10, 15 years ago.
"There is no reason in this day and age for that level or suspicion to continue. There is absolutely no reason."
Froome went on praise the crowds along the route for creating a "great atmosphere out on the road".
"The fans and supporters who are out on the roads – the thousands and thousands of people – they are the heart and soul of this race," he said.
"It's great to be received in that way and have that kind of really positive energy from everyone."
After Saturday's 14th stage Froome had complained that a fan had thrown urine at him and called him a "doper".
Richie Porte, Froome's team mate, had previously complained of being punched by a spectator along the route on Tuesday 14 July.
On Monday 13 July Team Sky principal David Brailsford complained that the team's computers had been hacked for data on Froome's power output in hopes of proving that he had used performance enhancing drugs.