You might know Selena Gomez for being a former Disney channel actress, for her acting and for her millions of followers on Instagram. 

But when fans hear her name, they also connect it to lupus. 

According to the Lupus Foundation of America, the disease can damage several parts of the body including the internal organs, joints and skin, which can cause the immune system to fail in discovering the differences between healthy tissues and foreign invaders. 

Though it isn't contagious, women are greatly affected by it than men, with the disease has the tendency to develop between the ages of 15 and 44. 

Symptoms of lupus may include chest pain, muscle pain, fever, hair loss, mouth or nasal ulcer, face rashes, extreme fatigue and many more. there are also different medications to treat the disease, but comes with side effects that include weight gain. 

In 2015, the "Lose You to Love Me" singer opened up about her health and shared that she was battling lupus. During that time, Gomez was undergoing chemotherapy to treat it. 

Two years later, she opened up about the autoimmune disease once again because she had a kidney transplant. On Instagram, Gomez shared in 2016 that a friend of hers had donated kidney to her. 

The singer-actress has been noticeably absent the past couple of years during her time of illness, despite promoting new songs. 

Fast forward to today, though Selena Gomez looks okay and healthy, the Instagram sensation has revealed that having lupus made her feel insecure as she has put on some weight in the last couple of years. 

Speaking to Cosmopolitan as she prepares to release her own cosmetics line, Rare Beauty, the brunette bombshell explained that she has had to change her mindset when it comes to her looks following her diagnosis. 

"I've gotten insecure. I also have lupus so I fluctuate in my weight a lot, so I've had to learn pretty early to have thick skin when it comes to this stuff, and to understand that it doesn't matter at all," she said. 

She bravely said, "It's all it is."

Selena Gomez added that this is why she's making sure that her cosmetics brand would not only just be a "brand," but more of a "community."

"So I wanted to find a way to make this brand into a community - into a lifestyle that's beyond makeup and showing you how to apply it." Gomez further said, "It's about talking about makeup and the relationship you have."

Though she created it, Gomez said she didn't want it to be all about her.

"I would be more proud to see the mission we have behind it as well as enjoy it." 

The 28-year-old star also revealed how the beauty world had inspired her get through the difficult period in her life. 

"Because I have struggled, very openly about anxiety, depression and mental health, I would say therapy and the time that I've taken for myself has actually just reflected everything that I've been releasing."

The "Same Old Love" singer added, "Two and a half years ago was when we started having the conversation, a lot of that bled into my mental health and the relationship that can be with yourself."

"I believe that it's mind, body and soul."

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