Eating junk food won't help you lose weight, but it's not only because those foods tend to be high in calories — it also has to do with insulin. Jason Fung, MD, a nephrologist (kidney specialist), explained that processed carbs and sugary foods such as ice cream, cookies, muffins, crackers, bagels, and white bread spike your insulin levels, which causes weight gain. Keeping your insulin levels low will help you reduce your overall body fat percentage, and that means belly fat.
Aside from being high in carbs and calories, eating these foods also doesn't offer your body any nutrition, so you end up feeling hungry, which makes you eat more. Eating sugary foods also increases your cravings for them, another contributor to overeating.
It's OK to enjoy sugary treats and processed carbs every once in a while, but if you cut down on these types of food, you'll definitely notice a difference in how you feel and how your belly looks.