It is not simply to say that it is better to be thin or fat. A moderate figure is the most important thing. If you are overweight, various metabolic syndromes may affect the quality of life. Being thin can lead to malnutrition, poor resistance and easy to get sick. Thin people are less likely to get high blood pressure and hyperlipidemia. Obese people have better physique and stronger resistance than thin people. If they can stay healthy, they'd better be fat.