Lizzo says her new weight loss is gonna have people asking if she got a Brazilian Butt Lift … and, she’s says TMZ had better investigate to put the rumors to bed.

The singer-songwriter posted a clip to Instagram yesterday … stunning in a red lingerie top and a pair of matching see-through pants — which did little to hide the underwear underneath.

Lizzo shakes her booty a bit … and, says the whole look is “giving BBL” — meaning she’s looking like she went under the knife to get a backside like that.

Lizzo says everyone’s going to come running to TMZ to find out if she got a BBL … and, while we don’t know for sure, we’d venture a guess and say her behind is sculpted from months of working out and eating right.

We’ve told you all about Lizzo’s weight loss … revealing she hit her fitness goals earlier this year. She’s been known to flaunt her figure in her videos — including one she posted late last month which showed her twerking in a pair of jeans.