1 . Why It’s Hard to Lose Weight

What makes people gain weight? This seems like a simple enough question to answer. If we eat a lot and don’t do enough exercise, we will become fat.     1    

As we know, what we eat greatly affects our weight. It is widely accepted that people have 100% control over what they eat and how much they eat. This, however, is partly true.     2     You may rarely touch vegetables while overeating fried chicken. Meanwhile, the serving size and the background music can both affect how much we eat.

Our bodies themselves can decide whether we are more likely to gain weight or lose weight. Scientists have found that the more delicious the food, the more excited our brains get.     3     Compared to people of normal weight, fat people feel more excited when they see delicious   food.

Also, our bodies use a variety of hormones (激素) to tell our brains whether they are hungry or full.   Ghrelin(胃饥饿素), for example, tells the brain that the body wants food. Leptin(瘦蛋白), meanwhile, tells the brain that it’s time to stop eating. Ghrelin and leptin help us to maintain a healthy weight.     4     As we get fatter, the levels of leptin in our bodies rises.   Our brains are told not to eat all the time. In the end, they would no longer trust leptin and would stop responding to its “warnings”. When we start to lose weight, leptin levels drop. Our brains think we are hungry and makes us find food in our fridge.

    5     They may have tried very hard, but their bodies are working against their will.