And now the pop star's latest health scare probably isn't helping to alleviate those fears.
"I'm very connected to my aunt, Joanne, who died of lupus," she tells The Times of London. "It's a very personal thing."
When asked if she's been tested, Gaga, 24, says "yes," without elaborating on the results, adding that she doesn't "want anyone to be worried" even though the disease, in which the immune system attacks the body, can be genetic.
"I have heart palpitations and things. But it's okay. It's just from fatigue and other things," the singer, who said she fainted during her New Zealand concert because of jet lag, tells the U.K. newspaper.
Her most recent health emergency: "The other day," Gaga says about her time in Tokyo where she was "having trouble breathing."
After receiving "a little oxygen," the "Bad Romance" singer went back on stage. "I was okay," she says, again adding, "I don't want anyone to worry."
As for buzz about her thin body, Gaga wants to reassure fans that she doesn't "have an eating problem," but rather points to her busy schedule that doesn't allow her "very much time to eat."
"I really don't do drugs. I don't touch cocaine any more. I don't smoke," she says. "I take care of myself."
But don't expect her to slow down anytime soon.
"People say I should take a break," says the singer. "But I'm like, 'Why should I take a break? What do you want me to do? Go on vacation?"