A、Because it takes time before your brain realizes that you’re full. B、Because the slower you eat, the less you absorb. C、Becaus

There are many ways to lose weight. First of all, start small. Small changes are a lot easier to stick with than drastic ones. Try reducing the size of the portions you eat and giving up regular soda for a week. Once you have that down, start gradually introducing healthier foods and exercise into your life.
    Second, stop eating when you’re full. Lots of people eat when they’re bored, lonely, or stressed, or keep eating long after they’re full out of habit. Try to pay attention as you eat and stop when you’re full. Slowing down can help because it takes about 20 minutes for your brain to recognize how much is in your stomach. Sometimes taking a break before going for seconds can keep you from eating another serving.
    Avoid eating when you feel upset or bored, try to find something else to do instead (a walk around the block or a trip to the gym are good alternatives). Many people find it’s helpful to keep a diary of what they eat and when. Reviewing the diary later can help them identify the emotions they have when they overeat or whether they have unhealthy habits. A registered dietitian can give you pointers on how to do this.
    Third, eat less more often. Many people find that eating a couple of small snacks throughout the day helps them to make healthy choices at meals. Stick a couple of healthy snacks in your backpack so that you can have one or two snacks during the day. Adding healthy snacks to your three squares and eating smaller portions when you sit down to dinner can help you cut calories without feeling deprived.