The head of WADA says the 34 current and past Essendon players who received 12-month doping bans were responsible for what went into their bodies.
The Court of Arbitration for Sport upheld WADA's appeal on Tuesday and imposed the sanction, meaning 17 current AFL players will not be allowed to play this season.
WADA director general David Howman said the players' lack of curiosity about the Bombers' controversial supplements regime was one aspect contributing to their suspensions.
"They've been educated so they are responsible for what went into their bodies," Howman told 3AW on Wednesday.
"The players were not consistent in what they told various people and the way the evidence was actually presented to the Court of Arbitration.
"The matters relating to each player came out in a different fashion including one who didn't even concede to his doctor, when treated for a special illness, that he had been taking these things.
"That could have led to real detrimental aspects to him health-wise."
Howman said WADA launched the appeal to CAS to ensure the standard of proof required in anti-doping cases was equal worldwide.
"It's not a question extending sympathy (to the players) when you have to administer laws, it's a question of following the process and following the laws properly," Howman said.
"If you stop doing that then you open up avenues of appeal for all sorts of people in all sorts of sports around the world."
AFLPA boss Paul Marsh on Tuesday called for the AFL to consider severing ties with WADA in the wake of CAS' decision.
Howman dismissed Marsh's criticism.
"We cater for all team sports throughout the world," Howman said.
"It's not as though the AFL is alone in this."