Revealing the secret of his amazing physique to E! News, he said he keeps a strict, lean diet, filled with proteins and low in carbs.
"It's really just being strict within reason," Derulo advises.
"...I was kind of doing just like those crash diets where I was going hard, going hard, going hard. [But] it's easy to fall off and when you fall off, it's kind of hard to get back up. So if you create yourself a reasonable diet...if you want something, you can have it, but within reason, do like an 80/20, 80-percent healthy and 20-percent...don't go too crazy!" he joked.
Derulo will be continuing his tour arounf the United States later this month, and is also set to perform for CMT Crossroads with Luke Bryan in the summer.