"But honestly, I don't care about my weight because people b**** about it anyway. 'You're too small, you're too big, that doesn't fit.'"
Selena - who has more than 300 million followers on Instagram - previously explained that her weight fluctuates because of her Lupus diagnosis.
The singer explained how her medication influences her weight.
She said: "I fluctuate a lot with my weight.
"It's the medication I have to take for the rest of my life - it depends on even the month, to be honest. So for me, I really noticed when people started attacking me for that. And in reality, that's just my truth. I fluctuate. It depends what's happening in my life."
Earlier this year, meanwhile, Selena admitted she's "excited" to turn 30.
The Lose You to Love Me hitmaker is set to celebrate her landmark birthday on July 22, and Selena can't wait for the next chapter of her life.
She explained: "I love growing up.
"When I was younger, I was scared of it, and I thought by now my life would look so different. But now I'm like, 'Wow, this is not what I ever expected, and I couldn't be more thrilled.' I've stopped caring about what people have to say, and that's been wonderful."
