We usually seldom know the good and bad that fat and thin bring us, in fact, many times, our body lightness determines our health. Some people want to be thin and slim, but really those who are thin may be the result of unhealthy body, so you can not be blind. Here’s a look at the relationship between weight and our life expectancy. The genetic thinness, BMI will rarely be less than 18 Thin people are part of the “genetic thinness”, in the long evolutionary process of human beings, the majority of people’s genes are evolved to the calorie intake can be quickly stored. Only a very small percentage of people have genes that are not good at storing calories, so they don’t gain weight by eating. Genetically thin people have normal health and rarely have a BMI below 18. BMI = weight in kilograms divided by the square of height in meters, which is the internationally accepted measure of how fat or thin an adult is. People with BMI <18 are abnormally thin For people with a BMI less than 18, being abnormally thin must find a reason. Statistics from the medical community found that the average life expectancy of people who are too thin is slightly lower than that of normal weight people, and because thin people have too little fat, they are relatively more prone to problems such as gastric prolapse and kidney prolapse, and they recover more slowly than normal people after falling ill. People become fat and thin will be in line with a law: dietary calorie intake > exercise consumption = fat storage dietary calorie intake < exercise consumption = fat consumption Thus, the following three factors determine a person's fat and thin: A, the presence of disease, so that the body can not absorb or consume too much energy; B, whether the dietary calorie intake is sufficient; C, whether the amount of exercise is too much. Many thin people always say, I do not have any reason, just can not eat fat, the actual is not seriously looking for reasons. Different ages, the common reasons for not gaining weight vary. Children Parents should consider whether their children have worms? Children who have worms always have trouble sleeping and grind their teeth at night. The loss of weight is caused by the worms that make the appetite worse and the food is not absorbed by the body. The presence of worms in the intestines used to be more related to poor hygiene. The current onset is more likely to be related to pet ownership and love of raw fish. In addition, children who are paranoid, such as eating only meat or vegetables, of course, do not grow fat, parents will have to improve the dietary habits, so that children a balanced diet. Adults 1, improper diet Some people do not grow fat is caused by poor eating habits. Clinically, some people will deliberately avoid eating after the disease. Received a middle-aged and elderly couple, six months of continuous thinning, careful questioning found that due to diabetes, increased exercise at the same time, only eat vegetables and drink milk, rarely eat starchy food; there is a patient's friends and relatives have diabetes, he was afraid of his own disease, self-restricted diet, a lot of exercise, of course, people will lose weight. Some diseases require a restricted diet, but this is to reduce the amount of intake under the premise of ensuring nutrition. 2, excessive weight loss Some ladies who love beauty take diet pills indiscriminately, and become anorexic and thinning. He once saw a female student who was one meter six but weighed only 60 pounds and was triggered by anorexia due to excessive dieting. Anorexia nervosa is a neurological abnormality that causes the patient to have no appetite at all. Some irregular diet pills on the market will suppress the central nervous system and affect appetite, as well as side effects such as depression and accelerated heart rate. 3, disease factors High metabolic diseases, chronic wasting diseases can affect weight, such as tuberculosis, diabetes, thyroid disease, tumors and so on. For example: hyperthyroidism patients, symptoms are mostly manifested as protruding eyes, palpitations, easily agitated, overeating, easy sweating, etc.; if you love to eat raw fish to raise pets, consider whether the birth of worms; whether suffering from gastrointestinal diseases, such as gastric disorders ate uncomfortable; anxiety patients do not rest well, consumption will increase, people will lose weight; female menopause in a sustained state of high metabolism, also prone to thinning. Chronic diseases are common in the elderly, such as diabetes can cause wasting, diabetic patients such as poor blood sugar control, resistance will be weakened, easy to get tuberculosis and other infectious diseases, to pay attention to. After these kinds of diseases are well, you can soon put on weight. Other people are not sick, but often stay up late working, the body consumes a lot, will also lose weight. To remind you that if the original fat people suddenly become thin, have to exclude the factors of disease. Appropriate weight gain General rule: exercise moderately reduce a little, eat a little more on the basis of balanced nutrition, so that the intake exceeds the consumption. In terms of diet, fat gainers should increase the intake of starchy staples and high-protein foods (fish, meat, eggs, milk). Measure weight once a month to detect changes in weight and adjust the diet. Weight remains the same: exercise the same amount and eat more. Weight is still dropping: it may be too much exercise and consumption, or for the diet intake is not enough, or the primary disease is not dealt with. A relaxed mindset, regular exercise, balanced nutrition, good rest, and timely prevention and treatment of diseases are the keys to maintaining a normal weight. Studies say that people with a BMI between 23 and 25 have the longest average life expectancy. Excessive body weight can increase the burden on the functions of various organs in the body and damage health. However, people who are lighter in weight are slightly weaker and cannot withstand unexpected situations such as illness. Being underweight can also bring damage to the body. I hope that readers pay proper attention to their weight so that they can have a healthy body.