The diagnostic criteria for obesity in China issued by the China Obesity Working Group in 2003 are: BMI<18.5 is underweight; 18.5≤BMI≤23.9 is normal weight; BMI≥24 is overweight; BMI≥28 is obese .
Body fat content refers specifically to the fat content in the human body; body fat rate refers to the fat content in the human body as a percentage of the body weight. The calculation formula for the latter is: body fat rate (%) = body fat weight/body mass *100%. Using the body fat rate evaluation method eliminates the phenomenon of excessive weight caused by developed muscles, bones, edema, etc., making the determination of obesity more accurate. The commonly used critical points for judging obesity by using body fat percentage in China are: male body fat percentage >20%, female body fat percentage >30% are obese; the most suitable body fat content is: 6%~14% of body weight for males. , 10%~14% for women.
Conclusion: The optimal body fat rate is below 14%.
The prevalence of hypertension in obese people is twice that of normal-weight people and three times that of underweight people. Moreover, the prevalence of obesity and hypertension increases with age. Upper body obesity is associated with further increases in blood pressure. Obese people are at a higher risk of suffering from hypertension and hyperlipidemia than those of normal weight. Hypertension and hyperlipidemia are important causes of arteriosclerosis, so the prevalence of coronary heart disease in obese people is also increased.
According to the latest research, about 10% of 10-year-old children in Beijing have early-stage arteriosclerosis lesions, with fatty streaks on their arteries, and 1/4 of young people aged 15 to 39 have middle- and late-stage lesions. If the causative factors are not controlled, the incidence of cardiovascular disease will definitely increase, and may even cause sudden death in young adults.
Obese people are at greater risk of developing diabetes, and this risk increases with the degree and duration of obesity. 80% of type 2 diabetes is caused by obesity. The prevalence of diabetes in obese people is four times higher than that in people of normal weight, and the prevalence of diabetes in severely obese people is as much as 30 times higher than that in people of normal weight. Among people with diabetes over 40 years old, 80% had a history of obesity before developing the disease.
Cause analysis: Essentially, it is a decrease in pancreatic beta cells and functional disorders
Obese people will cause a large increase in blood sugar due to a large intake of high-fat and high-calorie foods, stimulating Pancreatic beta cells secrete large amounts of insulin to reduce blood sugar to the normal range. In the long run, the islet β cells are overburdened, causing the function of the islet β cells to decline, the islet β cells to fail, and the function of lowering blood sugar is lost, leading to diabetes.
In obese people, the fat cells proliferate and enlarge, and the size of the fat cells increases significantly by 2 to 3 times, just like an inflated "balloon." The number of insulin receptors distributed on the tissue cell membrane is significantly reduced, thus making the tissue cells insensitive to insulin. The effect of the same amount of insulin is weakened, and insulin resistance occurs. More insulin is needed to reduce blood sugar to normal levels, thus Increase the burden on pancreatic beta cells.
Therefore, the length of the history of obesity has a more important impact on diabetes than the degree of obesity. If obesity persists for too long, pancreatic beta cells will experience secretory fatigue or failure, causing blood sugar to become higher and higher. , eventually leading to the occurrence of diabetes.
Diabetic patients who lose weight will greatly reduce insulin resistance and the burden on pancreatic beta cells, which will help maintain blood sugar in the normal range for a long time, reduce the dosage of hypoglycemic drugs, and even eliminate the need for hypoglycemic drugs. Weight reduction in overweight and obese patients can also reduce or delay the occurrence and development of diabetes and its chronic complications.
Due to excess energy intake, it is converted into fatty acids and transported to the liver. The liver cells cannot digest them all, causing fat infiltration in the liver cells, leading to fatty liver. Severe fatty liver can evolve into cirrhosis.
Obese people are 6 times more likely to develop cholelithiasis than those of normal weight. This is because obese people have high cholesterol and are less active, so they are more likely to form cholesterol stones.
For people aged 40 to 45 years old, the mortality rate increases by about 1% for every 0.5kg increase in weight. When the body weight exceeds 25% of the standard weight, the mortality rate can increase by 74%.
The 2017 JAMA research report shows: The study found that compared with people who maintain a stable weight in young and middle-aged people, even if they gain only moderate weight before the age of 55 (weight gain of 2.5 to 5.0 kg, that is, 5 to 10 pounds) also significantly increases the risk of chronic disease and premature death, and reduces the likelihood of healthy aging. More weight gain is associated with greater risk of chronic disease. This research was published in the latest issue of JAMA on July 18, 2017.
Every 5 kg (10 pounds) of weight gain in youth and middle age is associated with a 30% increase in the risk of diabetes, a 14% increase in the risk of hypertension, an 8% increase in the risk of cardiovascular disease, and a 6% increase in the risk of obesity-related cancer. It is associated with a 5% increase in mortality (for never smokers) and a 17% decrease in the chance of achieving "healthy aging". /s/upomrjh9niGoUXzupQCR_Q
Overnutrition is the main cause of obesity. The two fundamental factors that affect body weight are heat energy intake and heat energy consumption. When energy intake is equal to energy consumption, it is called energy balance; when energy intake is greater than energy consumption, it is called positive energy balance. Energy is stored in the body in the form of fat, thus causing obesity; when energy intake is less than energy expenditure, it is called a negative energy balance and weight loss. Obviously obesity is in a state of positive energy balance. Such people generally have a very strong appetite and prefer high-sugar and high-fat foods. The excess energy is converted into fat, thus leading to obesity.
With the progress of society and the improvement of people's living standards, people's opportunities to engage in physical labor have been relatively reduced, so energy consumption has also been reduced accordingly. Epidemiological surveys have found that among adults and children, people who do not participate in exercise are prone to obesity or excess weight, while people who actively participate in physical exercise generally have a normal weight.
Among the causes of obesity, heredity has always been the main factor. is a factor that cannot be ignored. Obesity has a familial tendency. Research reports that if both parents are obese, the probability of their children being obese is "75%-80%"; if one parent is obese, the probability of their children being obese is 50%; if both parents are of standard weight, the probability of their children being obese is only 10%. . This may have a lot to do with the hereditary nature of obesity and the family's dietary structure and eating habits.
?Some studies have shown that once offspring become obese, their degree tends to exceed that of their parents. Obesity that begins in early childhood is more heritable than obesity that begins in adulthood. Therefore, preventing obesity in children and adolescents is of great significance to reducing familial obesity.
Insufficient exercise leads to energy metabolism imbalance, which is the main cause of obesity.
a. High-intensity exercise to lose weight: High-intensity exercise consumes more sugar and water than fat, which can easily cause insufficient brain function.
b. Dieting to lose weight: Dieting will cause insufficient nutrient supply, damage human immunity, and have great harm to health
c. Gain muscle and lose weight: it cannot increase the basal metabolic rate. The efficiency of fat loss is very low
The absorption and conversion efficiency of sugar is about 70%, the absorption efficiency of fat is about 96%, and the absorption rate of protein has no fixed value. The amount you lack is the upper limit of your absorption. So obviously, eating less fat and sugar and increasing protein intake is key at this time. A study in the United States showed that high-protein breakfast can help lose weight. According to blood tests, compared with the food-deficient group, the high-protein group had less growth-promoting hormone that stimulates appetite and more peptide YY, the hormone that suppresses appetite.
Walking or climbing a little faster (considering the tolerance of the knee joint) will have the best effect on achieving slight breathlessness. Among aerobic exercise, water exercise is considered to be the most promising way to lose weight because of its small impact and non-weight-bearing characteristics. At the same time, weight loss equipment like the current emerging weight loss method is also a good way to lose weight. Healthy people require the heart rate to reach 60%-70% of the maximum heart rate (220-age) during fitness training.
In the early stage of exercise, 70% of the energy consumed is glycogen and 30% is fat. When the exercise time exceeds 30 minutes, fat consumption begins to gradually increase, accounting for about 50%. In addition, moderate exercise before meals can effectively reduce fat and achieve weight loss and health care in the near future. Japanese medical knowledge believes that losing weight after a meal is not as good as before a meal. Because just after eating, the body's blood sugar rises and fatty acids enter the fat cells from the blood. Exercise at this time cannot effectively reduce fat. On the contrary, moderate exercise before meals will consume more energy because brown fat (an anti-obesity substance in the human body) moves away from hot meals in the body, so more fat will be reduced!
According to the British " The Daily Telegraph reported that many studies have shown that sleeping at least 7 hours a day can increase the chance of successful weight loss. There is increasing evidence that lack of sleep stimulates our brains to send hunger signals and changes endocrine, thus affecting appetite. , making people eat more. In a separate experiment, subjects were divided into two groups, sleeping 5.5 hours and 8.5 hours a night for 2 weeks, and eating only low-calorie foods.
The results found that subjects who slept for 8.5 hours burned 55% more body fat and built 60% more muscle than those who slept for only 5.5 hours.