JUSTIN BIEBER THROWS UP TWICE ONSTAGE DURING ARIZONA CONCERT

Milk supposedly does the body good, but not for Justin Bieber.

During his Glendale, Ariz. show on the Believe tour Saturday (Sept. 29), the Biebs performed his entire concert like a trooper even though he blew chunks not once...but twice onstage.

According to THR, the 18-year-old heartthrob threw up during a performance of "Out of Town Girl," where he ran off stage while his dancers moved along and a staff member cleaned up the mess. He then apologized to fans, "I'm sorry, I'm going to slow things down" before launching into an acoustic rendition of "Fall."

A few numbers later, the "Baby" singer ran off-stage during a pre-recorded performance of his Nicki Minaj-assisted "Beauty and the Beat," only to emerge with a second round of sorries. "It's hard for me, you know, not feeling great and throwing up in front of a bunch of people," he said. Bieber then asked the thousands of Beliebers in attendance if they still loved him even if he was throwing up onstage to which he received an emphatic "Yes!"

Bieber later tweeted that "Milk was a bad choice," citing the dairy product as the culprit for his messy show. Peep footage of the hurlage below.