The worst part about those kinds if posts is people who are that fucking fat can lose weight much more quickly and much more easily than someone who is merely overweight by BMI.  When you're morbidly obese, you require a huge amount of calories per day to maintain your weight.  You can cut back significantly but still be eating way more than a healthy weight person, and you'll still lose weight pretty fast.  Meanwhile, someone who is just overweight has to work a lot harder on controlling their diet because they're eating at a smaller deficit and eating relatively much less food overall than the morbidly obese person who is also losing weight. So for example, being 390 pounds and taking a whole year to get down to 350 pounds is laughably bad.  It's nothing at all to brag about.