system
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human
ELI5: Losing fat, how does it work?

I heard from someone that you fat goes away from certain areas of your body at a time in a certain order. For example, I can do workouts that work all parts of my body but I will only start to lose fat in one area first (I think it's the neck) and then the next area after the first area is fat-free and so on and so forth. If this is true, what's the best way to exercise to lose the most amount of fat in the shortest allotted time? 

Edit: if that's not how it works, then how does it really work?
gpt
"Spot training" does not exist. 

So if you do ab-workouts, fat will not burn from your belly. You will certainly build muscle, but it will exist *under* the fat. 

To lose fat, the best thing you can do is calorie reduction. This is actually the ONLY thing you need to do. Get an app on your phone like MyPlate LIVESTRONG and keep track of everything you're eating. There's a massive database of virtually any food you'll come in contact with. When you start, you will type in your information (height, weight, age, sex, activity, etc.) and the app will tell you how many calories you need to eat per day to lose weight. Usually, if you need 2,000 calories to maintain, you should drop about 500. 

You can start easily by cutting out all sugary drinks and replacing it with unsweetened tea, black coffee or water. Avoid diet-drinks because they tend to be bad for you in high-amounts for other reasons. Replace cooking oil with 0-Calorie Cooking Spray. Anytime you have the option of getting a sandwich, get it in a wheat wrap. Avoid cream-based soups and go for broth. Order chicken/fish instead of red meat (unless its Bison. Bison is very lean and has 2/3 less fat than chicken). Note: hot sauce is really good because its basically 0-calories. 

Also, this is probably the toughest thing, but instead of doing 2 or 3 meals a day - try doing 5 *small* meals throughout the day, starting with breakfast. This keeps your metabolism *constantly* in action. 

Again, this is the ONLY thing you really need to do to lose fat. 

If you want to add to it, aerobic exercise is best. You don't have to "feel the burn", just get your heart rate up and sweat. 140 minutes a week is recommended.  That's 20 minutes a day, or 40 minutes every other day. Jogging, Jumping Jacks, Biking, Rowing, etc. You know what you can do? Buy a PS2 and a copy of Dance-Dance-Revolution from your local used-gameshop and do that for 20 minutes everyday. 

The rule for losing fat is "Last in, first out." So if you've had a gut for a long time, it'll be a while before you notice it going. But don't let that discourage you: it WILL go.