1、A review of 30 years of epidemiological study on childhood obesity in ChinaDing Zhong Yi，.Hu Ya Mei and Zhang Jin ZheNo other disease attracts so much attention from people of all age groups like obesity， No other disease causes so much contradictory views and interpretations like obesity； No other
2、treatment intervention attracts so much crazy investments of money， time and emotions like weight losing from people of all age and sex groups， No other disease causes so much opportunities of making big money for pseudoscience and businesses like weight losing. Obesity is an inevitable disease caus
3、ed by life-style of post industrial society， a waste of social energy， a retrogress of the biological revolutionary process， and a loss of traditions and cultures.The 3rd epidemiological study on obesity among children of 0-6years in China by National Task Force on Childhood Obesity means that our n
4、ations study on childhood obesity has been going on for 30 years. These 30 years of hard work and achievements are really worth of good summing up and recalling.We pediatric professionals in China began to make academic preparations for study on childhood obesity in 1978. We first read extensively t
5、he foreign documentations and carefully analyzed the documents of the first international conference on childhood obesity held in Italy in 1978. There existed， at that time,contradictory observations and conclusions on obesity in the international academic field in terms of definition， diagnosis sta
6、ndards， harm caused by obesity and intervention of obesity and we could not find any data for reference.We found it very difficult at that time to locate a fat child of 0-6years in China. But we still began to accumulate data on depth of subcutaneous fat of small groups of people and set up to estab
7、lish an under-water lab of weighting. After the a consensus conference held by NIH in 1985 to consolidate the standards on obesity， things got much better in the international academic field in that people had at last a consolidated thinking and standard on obesity in terms of major methodology.But
8、2 big unknown factors still existed : the first was whether obesity could happen to children of 0-6 years and the second was whether obesity could cause immediate harm to the health of such children during the time span of 0-6 years. It was only known at that time that obesity was an important facto
9、r of cardiovascular diseases but that was the conclusion of Freiminghem survey and was not a conclusion of study on obesity itself.After the consensus conference held by NIH in 1985 to consolidate the standards on obesity，we started to prepare for the epidemiological study on obesity among children
10、of 0-7 years in China in 1986. We as a working unit made many achievements ，innovations ，and progresses in the field of study on child obesity since then: We were the first in China to start studying obesity among children of 0-7 years(1，2)，and this study was redone in the next 10 years and renewed
11、in 2006 for the third time（3,4）.We were the first in China and overseas to report the harm of obesity to the capability of children(5) and set a prescription of exercises for children (6). We were the first to report the test evidence of harm of obesity to the behavior-psychology of children(7).We m
12、ade some researches on the relation between child obesity and hypertension of blood and the related danger factors（8,9）.We make a curve of distribution and cut-up point of Kaup/BMI index which is suitable for Chinese children(10). We wrote and issued a set of treatment rules on preventing and curing
13、 of childhood obesity(11). We later on also began to do molecular researches on Childhood obesity (1215).Based on above researches We clearly indicated the definitions of child obesity and also pointed out that child obesity is a disease of lifestyle closely related with daily habits instead of a di
14、sease of, or an affiliated factor of cardiovascular diseases among adults.We put forward guidelines that calls for preventing child obesity from the time of pre-pregnancy which include: nutritional preparations during pre-pregnancy period ，nutritional monitoring during pregnancy, nutritional support
15、 during breast feeding period, deepening and strengthening breast feeding , using key nutrients similar to human milk to do，strengthening paste food feeding，and emphasizing“natural food and balanced feeding”principle during the period of feeding babies with solidstate food（1821）.The above researches
16、 were of a leading nature not only in China but also internationally. We were invited to make a key-note report on the research we did in China on child obesity in 2001 at the 23rd International Pediatric Conference, and were invited to make a speech as the only scholar to do so from China at the 11
17、th Asian Pediatric Conference held in Thailand, whereas the speech was a review of the research achievements and latest progresses we made within the framework of National Task Force on Childhood Obesity, China from 1978 to 2003.The China Medical Foundation awarded a Yang Cong Rui prize of health fo
18、r women and children to Ding Zong Yi in 2002 and highly praised the creative research made by the Task Force in the field of child obesity and the contribution it made in organizing the research by the Chinese pediatric circles on child obesity. He Qing of Pediatric Institute of University of Columb
19、ia of USA （also member of National Task Force on Childhood Obesity, China）also received a Prize of Academician Hu Ya Mei and Zhang Jin Zhe at the 3rd Asian Pediatric Nutritional Conference because of his remarkable research in the field of.1Views based on epidemiological researchesWe made a forecast
20、 after doing some researches in 1986 that obesity would be a health problem for Chinese children when the prevalence of obesity at that time was only 0.9% (2). We renewed the forecast in 1996 that obesity had become a severe health problem for Chinese children and would become a severe social proble
21、m if uncontrolled properly when the prevalence of obesity at that time was 2.0 and 4.2 respectively (3). The problem of child obesity was severely out of control in 2006 and the prevalence of obesity and overweight at that time was 7.2 and 19.8 respectively which were up 3.6 and 4.7 times than the f
22、igures of 1996 (3). That increase is related in some way with the high speed economic growth of about 10% in China but also related with other factors such as weak resistance against trash food， heavy and unregulated advertising of food，improper propaganda of urban lifestyles which all had an impact
23、 on people in different ways.2How to view childhood obesity？1 What does obesity mean Obesity can be viewed and interpreted in many perspectives such as physiology， biochemistry，biological evolution，behavior science， sociology and economics. From the perspective of economics, obesity is a waste of so
24、cial materials and energy. It distorts the distribution of social resources, cause the unreasonable allocation of public health resources，and delays the sustainable development of social economy. So, containing the growth of population with obesity problems is a social-economic issue which should be
25、 urgently solved by countries and especially developing countries in their planning of social development.2 Viewing obesity from the perspective of culture. The reason that causes so many people get fat is they have an unscientific and incorrect lifestyle. Such a lifestyle is very in vogue，luring an
26、d evidently erodes the traditional and correct lifestyle. Viewing from the perspective of progress of society and culture and keeping a social ethics with good cultural properties， containing the growth of population with obesity problems is a significant issue of protection of socialcultures.3 Refl
27、ecting from the perspective of biological evolution. The fat tissues in the human evolution have a meaning of keeping energy， defending against hunger and protecting the life. When obesity happens the fat tissues would overgrow and pile up， losing the positive meanings in the process of human evolut
28、ion and endangering the human health instead. At this time the pure elimination of some parts of fat tissues would not stop the remaining “bad ”fat from doing further harm. We strongly feel based on our research on dying of fat tissues that the so called weightlosing treatment aimed at eliminating l
29、ocal fat or blood fat is to no avail, and sometimes can stir up or intervene with the distorted dying process of fat tissues and increase the over-growing and piling-up of the fat tissues.4Viewing from the perspective of aesthetics. The modern people seem to think that to be thin is beautiful. Obesi
30、ty brings no sense of beauty to people and erodes fat peoples self-pride and sense of self-image. Faced with life that is getting better and colorful more and more and a pilingup of fat tissues, people begin to admire the spirit of Olympics and recall their ancestors who were once so strong，healthy
31、and powerful.5 Viewing from the perspective of body development. If child obesity is a deviation in the process of body development ，then adult obesity is the first signal of aging. the reason why obesity is a danger factor of many diseases of old people( hypertension,)is that it indicates the begin
32、ning of the aging process.6 Implications and opinions As obesity is a chronic disease closely related with lifestyles so people have to avoid letting children lose weight in a short time， avoid using hunger or covert hunger to treat such children, avoid using medicines or diet drinks to treat such c
33、hildren，and avoid using operations or physical interventions to treat such children. Those means have proved to be harmful for body development and health and are not sustainable.Our definition for child obesity is: it is a chronic disease closely related with lifestyles and has indications such as
34、over-eating, too less physical exercises， behavior deviations and has an end result of overpiling of fat tissues in the whole body.Our research in the past 30 years has proved that our above definition is scientific, so we should have correct views and right interventions faced with the 3 indication
35、s of child obesity when we do clinical and on-site treatment. Our above definition seems to leave no room for heredity.as there is till now no evidence that shows people could be fat because of gene mutation. The detection rate of obesity in China and overseas have increased remarkably in the last 3
36、0 years but our genes have never changed. Many misconceptions on this point mistake family aggregation for an expression of heredity. Family aggregation is just a collective expression of certain behavior and an indication of life style.A big percentage of people with obesity problems will be fat du
37、ring their whole lives and can not reduce their weights to the normal scope. They do not need to try very hard to lose weight if they are always in a good healthy state. The indications for a good healthy state after treatment is: aerobic capability（including exercising capability） is increased, fee
38、ling happy, mentally healthy, being able to give full play to his or her potentials, mastering correct nutritional knowledge and knowledge about lifestyles, and being able to control and condition his or her own daily life.3Is obesity a endocrine disease ？That is a most common misconception among do
39、ctors when they first face obesity. That misconception would be strengthened further when they find that obesity is a risk factor for CHD in adulthood and they also find the patients have some other harms . They often believe these related harms for the health are the independent harms of obesity it
40、self. Our study on adult patient cases has proved that most doctors have such conclusions which in our view are wrong. From the perspective of methodology, the complecte consequence are not the same with the original disease and a risk factor is not the same with the direct harm. Based on our search
41、 of medical theses, none of them has proved that child obesity is caused by endocrine abnormality，or obesity is caused by original endocrine disease according to natural history on obesity. We believe no means of endocrine so far can intervene with the process of obesity.Obesity harms our mind and b
42、ody at the same time: It harms our arobic capability and physical fitness(5)，and also causes the abnormality of character and behavior, makes the patient unable to give full play to his or her potentials，and delays our attainment of related capabilities(7). Aerobic capability is the basis of the phy
43、sical fitness and only influences the health level of childhood but also influences the health level and life quality in later stages(17). For the kids with child obesity problems， being harmed in the aerobic capability when very young is a severe damage which could not be repaired for the whole lif
44、e. Such harms can not be found if we look into cases of child obesity only from the perspective of endocrine disease. Even if some patients show abnormal indications in some parameters, the doctors still can not give it a complete explanation as a kind of disease of endocrinology and develop a strat
45、egy to cope with it.4What kind of a tissue is the adipocyte tissueAdipocyte tissues are not a static “ warehouse ”and do not simply have a “ linear ”correlation with volume of food intake and volume of physical exercises. Adipocyte tissues are an active organ having many functions such as: endocrine
46、， adjustment, nervous endocrine， temperature control, mechanical protection, behavior conditioning. We can not use the simple thermo formulas in “ test-tube science ” to estimate and forecast the piling-up and decreasing of adipocyte tissues.Adipocyte tissues have a strong“memory” . All the “nutriti
47、onal stimulus”（including hunger ，overintake of food，too high intensity of nutrition） they get during pregnancy， baby and child period， and puberty will change the emission of signal from the program controlling the apoptosis of adipocyte tissues and cause it to move to the direction of low intensity
48、 and“ remember” the message. When they get renewed similar “nutritional stimulus”during other times after puberty, they would give a strong expression of decreased control on such apoptosis.Adipocyte tissues are related with but are not the same with it as they have different location of operation a
49、nd different biological properties. Blood fat is more an expression of function of nutrients, including the function of nutritional support and nutritional toxin. But adipocyte tissue are more an expression of physiological function. Here we meet with many questions which need to be explored: the socalled decreasing of blood fat means or the adipocyte tissues 5.Our hopes and wishesAcademician Zhang Jin Zhe pointed out in discussing the scientific meaning of the work done by the task force: Task Force on Childhood Obesity of China
