DO I LOOK FAT?
How do you tell the woman in your life that those pants really do make her look fat? If she’s bothering to ask the question, she already
knows the answer. She doesn’t want you to disagree; she wants your help.

If you decide to be honest here are a couple of Suggestions

“They’re not the best on you”
“They aren’t the most flattering.”

Why does she want your input? Because you’re there and another woman isn’t.
‍

Source: Esquire magazine, 8/11/21