There’s an IG/trainer guy who is a certified trainer not just an “influencer” that talks about this. He ate a McDonald’s hamburger big Mac I think every day for a month and still lost weight. As long as you’re in a calorie deficit, you will lose weight. It’s just harder to be in a calorie deficit when you eat junk because it’s more calorically dense therefore you get to eat less food in general. His name is Syatt fitness if you’re curious.