Pop star Justin Bieber took to Instagram on Wednesday to address rumors about his "sickly" appearance. 

Bieber said he was recently diagnosed with Lyme disease, a disease caused by the bacterium spread by ticks. 

"...not only that but [I] had a serious case of chronic mono which affected my, skin, brain function, energy, and overall health," Bieber said in the post.

The "Love Yourself" singer said more details on his health will be discussed in his upcoming documentary series Justin Bieber: Seasons set to arrive on YouTube January 27.

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