Don't be afraid of obesity.

Fat and healthy longevity can coexist.　　A recent study published in the Journal of the Canadian Medical Association confirms this conclusion.　　Another study in the American Journal of Applied Physiology, nutrition and Metabolism and the Canadian Medical Association also tells us that fats can live long and healthy lives.　　So fat is not a sin, keeping your weight stable is a healthy way to live.　　A How heavy is called fat? The BMI standard is currently used to measure obesity in a broader way.　　That is, weight (kg) divided by height (m) squared, if the result is 18.5 to 24.9 (kg/m²) is normal weight, 25.0 to 29.9 (kg/m²) is overweight, and 30 (kg/m²) is obese. This standard was originally designed for statistical tools for public health research.　　Previous studies on a large number of cases also did show that when the BMI was more than 25 per 5 units, the overall mortality rate in the studied population increased by 29%, with cardiovascular disease mortality rising by 41%, and diabetes and associated causes of death by 210%. However, with the further research, the limitations of BMI are also obvious. For example, some people may be healthier than many people with lower BMI, although they have a high BMI.　　Another major limitation of BMI is that it does not directly reflect the complications associated with obesity or the decline in quality of life, which is critical to the clinical diagnosis of obese patients. In addition to BMI, another commonly used indicator ——— waistline, has similar limitations.　　[Page]　　B how fat is easy to get sick?　　Canadian scientists have tried to build a more scientific system, the Edmonton Obesity grading system (EOSS), for more accurate diagnosis and treatment of obese people. The system divides them into 5 levels (0-4) according to the health of obese people (with a BMI value greater than 30): 0 represents no obvious health problem, 1 is a slight problem, such as blood pressure and blood lipid standards to reach the upper limit of health standards, the body occasionally have pain symptoms, but did not reach the level of need to seek medical care 2 to 4 indicate chronic diseases such as hypertension and type II diabetes.　　The higher the rank, the more severe the symptom. The researchers, after classifying a large number of cases, found that patients of grades 2 and 3 (because of the severity of the Grade 4, which is less seen in the case and therefore not included in the statistical results), the overall mortality rate and the mortality rate of cardiovascular disease are significantly higher than those with normal weight; grades 0 and 1 of patients,　　There was no significant difference in mortality among those with normal weight.　　It turns out that subjects with grades 0 and 1 had a BMI of more than 30, but were in good health and did not differ significantly from those with normal weight. Scientists have carefully studied the differences between obese people at different levels, mainly on their weight-loss histories and habits. This found that 2 and 3 of obese people with grades 0 and 1 compared to the amount of exercise is smaller, the intake of vegetables and fruit is not enough;The daily diet of 0 and 1 of obese people contains more fruits and vegetables, as well as a certain amount of exercise.　　Interestingly, the study also found that healthy obese people tended to maintain a more stable weight over the years, while obese people of grades 2 and 3 had a much richer history of weight loss. C-body weight more healthy try to lose weight more often, weight has experienced more reduction and increase cycle, this weight loss experience is also known as "yo-yo" weight loss. Studies have shown that this "yo-yo" cycle of weight loss may increase the risk of mortality, especially in cardiovascular diseases, caused by various diseases.　　Today's statistical studies of Eoss indicate the existence of this possibility. Repeated movements of weight may result in a decrease in the body level of a substance called high-density lipoprotein cholesterol. HDL is responsible for transporting cholesterol in the body, which can transport cholesterol from the arteries to the liver and make it available again, thereby inhibiting the occurrence of cardiovascular disease.　　If "yo-yo" weight loss results in lower HDL cholesterol levels, it is not surprising that there is a rise in the incidence of cardiovascular disease in people with this weight loss experience. Dr Cook, who participates in the study, says that through the Eoss system, it's easier for doctors to tell who needs to lose weight and who's doing well, after all, it's unscientific to make all fat people lose weight.　　The researchers believe that about 20% of obese people have no obvious health problems. Although the study itself has some limitations, the BMI as a measure of obesity does not satisfy the accuracy of the study. Before more comprehensive research results come out, if you are overweight but not disease-obsessed, instead of actively losing weight, it is better to eat more fruits and vegetables, and stick to exercise.