After completing all six of the lifts he attempted, Ilyin became the first weightlifter to successfully defend an Olympic title at the London games, prompting an outpouring of joy from the flag-waving Kazakhstan contingent in the crowd.
"Today I feel very, very different to what I was four years ago ... the training is not that much different but the quality of my victory is very different," he said.
"Here, at the age of 24, I gave everything tonight, everything for this triumph. It's not just a gold medal for me, it's a triumph."
He also said the Kazakh team's decision to import horsemeat to London had helped.
"I have to be careful with what I eat. Chicken and horsemeat are the best foods for weightlifting, good food is very important," he said.
Ilyin set a world record for the clean and jerk lift with 233kg and, when combined with a 185kg snatch lift, also set a world record for the overall total with 418kg - 12kg higher than his total in Beijing.
One of the few lifters to wear a costume bearing his own name, Ilyin won the backing of the neutrals in a packed arena at London's ExCel Centre with his no nonsense technique and faultless execution.
Whereas other lifters spent time over the bar adjusting their grip and composing themselves, Ilyin simply bowed deeply, walked to the bar and hauled it to shoulder level in almost a single movement, before powering it above his head and locking out his arms.
Although the result rarely looked in doubt, silver medallist Ivanov had a chance to take top spot and put the pressure on Ilyin with the penultimate lift of the competition, but he was unable to hold the 229kg barbell above his head.
That left the Kazakh secure in first place and free to raise the weight of his final clean and jerk attempt to a world record, which he subsequently completed with a minimum of fuss.
The bronze went to Moldova's Anatoli Ciricu whose lighter bodyweight put him ahead of Russia's Andrey Demanov after both finished with a total of 407 kg.