She put daylight in between her black boat and her rivals on a choppy morning session in Milan, pulling away over the last 100m to win in 1:49.398 minutes, 1.727 seconds clear of rising Hungarian Anna Karasz, with Yu Zhou (China) a surprise third.
"I had an idea I was in the lead but I couldn't back off it at any stage," the 26-year-old said.
"It was a tough race and I had to be really prepared to give it everything and do what I could because the competition was so strong. I couldn't leave anything up to chance."
The win completed a near seamless 500m progression for the New Zealander, who finished third in 2013 and second last year at the world champs. She also became the second non-European to win the 500m title after Canada's Caroline Brunet from 1997-99.
Last night, Carrington defended her K1 200m title, the same event she won at the 2012 London Olympics.
Despite a slow start, she won in a time of 40.06 seconds, about half a second ahead of second-placed Marta Walczykiewicz and just over one second ahead of third-placed Teresa Portela.
Carrington admits the chance to compete at the top in both events was helping keep her competitive fires burning.
"It's all about keeping the challenge and trying to get better and better every year and every day.
"It's allowed me to become a better paddler and, as I get older, I seem to get fitter and stronger and work on more things."
