IJE Advance Access originally published online on December 8, 2005
International Journal of Epidemiology 2006 35(1):12-14; doi:10.1093/ije/dyi250
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Commentary |
Commentary: On ‘public health aspects of weight control’
University of California, Los Angeles, CA, USA. E-mail: breslow{at}ph.ucla.edu
My comment on the paper1 touches briefly on: (i) the context at the time of writing it, (ii) some important advances on the topic since that time, and (iii) the current obesity epidemic.
The paper appeared as part of a growing chronic disease control programme in the California Department of Public Health, which reflected recognition of the epidemiological transition, i.e. ascendancy of the chronic non-communicable diseases over the communicable diseases as the major health problems.2,3 In particular, cardiovascular disease had been expanding substantially during the first half of the century owing in considerable part to excessive weight among increasing numbers of people.
Not all public health leaders immediately accepted the idea being advanced that public health should become involved in chronic disease control. The California Director of Public Health first advised, when I initiated such a proposal in 1946, to ‘go back to Minnesota (where I had come from) and try those notions out there.’ He later agreed to establish a Bureau of Chronic Disease in the Department when federal funds became available for cancer control. Kenneth Maxcy, who asked me to write a chapter on chronic disease for the 1951 edition of Preventive Medicine and Hygiene, insisted that the title of the chapter be Diseases of Senescence. This mirrored the common belief that cardiovascular disease, cancer, and the like were ‘degenerative’ diseases due to aging and not preventable. We compromised on Senescence, Chronic Disease, and Disability in Adults.
The scientific base for including weight control as an important element in the public health approach to the chronic disease problem then consisted largely of the findings by life insurance company actuaries and by Public Health Service statisticians.4,5 Experience in ‘rating’ life insurance premiums to reflect mortality risk showed that being overweight constituted a substantial mortality risk and that losing excessive weight returned people towards the ‘standard’ mortality pattern.6
The 1952 paper on Public Health Aspects of Weight Control suggested three approaches for public health to adopt for obesity control: (i) popularize the ideal of optimum weight as an aspect of good hygiene; (ii) for those who are already overweight, group therapy led by a health professional; and (iii) studies to refine knowledge of obesity and its control.
During the latter part of the 20th century knowledge about being overweight and its health impact advanced considerably. It became common practice to measure weight as body mass index (BMI), i.e. weight in kilograms divided by height in metres squared (kg/m2). Although arguments continued about the significance of various ranges of BMI in various segments of the population, BMI of 25–30 was frequently called overweight and >30, obesity. Observing that standard minimizes the difficulties of comparing different studies that previously had established various cutpoints for overweight and obesity.
Probably the major advance in understanding the relationship of obesity to health has come from studies of how physical activity affects mortality among the overweight. Morris' investigation of London bus drivers and conductors led the way generally towards knowledge of the role of physical activity in health.7
A California Bureau of Chronic Disease follow-up of mortality among ‘3992 longshoreman, averaging 17% over (Metropolitan Life Insurance Company) standards of weight for height, showed no excess mortality from all causes and no excess from coronary heart disease during the first 5 years after examination’; there was no gradient even among those 40% or more over the Metropolitan standard of weight for height.8,9 Presumably the heavy labour of longshore work had established a fitness among them that overcame any negative impact of being overweight. Further studies of the longshoremen's experience confirmed the original findings.10,11
Investigation of mortality among the more than 20 000 men who had attended a fitness centre revealed that obesity did not appear to increase mortality risk in men who were physically fit, measured by treadmill test; and that unfit men who became fit achieved a considerable reduction in mortality.12–14 Further, physically fit overweight and obese men had lower rates of all-cause mortality than normal-weight men who are unfit.15 Nearly 10 000 women showed a similar relationship between obesity, fitness, and mortality.16
Before physical fitness was known to enter into the situation so strongly, public health approached obesity almost exclusively through nutrition, i.e. by dealing with calorie intake. Nutritionists, of course, also pursued the matter of fat consumption beyond its contribution to excessive calories; they also studied its relationship to blood lipids as they became recognized as a factor in cardiovascular disease. Thus, public health agencies mounted efforts to persuade people to eat healthier foods. Campaigns and projects to induce people to eat more fruits and vegetables and less fatty foods in order to reduce obesity and cardiovascular disease became commonplace. Dieting became faddish; and sponsors' names became attached to their particular formulations. Specifics concerning various vitamins and minerals were often included. ‘Crash’ diets became popular, but any weight lost thereby was usually then quickly regained. As might be expected in a market economy without much regulation and where the notion that pills will secure health prevails, dietary ‘supplements’ were marketed and became a big industry in the United States.
Meanwhile overweight and obesity became epidemic. While 45% of United States' residents aged 20–74 years had BMIs > 25, already in 1900–62, the proportion increased steadily to reach 66%, age adjusted, in 1999–2000.17 The proportions were higher in Mexican-American and African-American families, but the increase among children and adolescents generally was particularly alarming. Among those 6–11 years of age, overweight increased from 4.2% in 1963–65 to 15.3% in 1999–2000; and among adolescents 12–19 years of age, from 4.6 to 15.5%.
Corresponding data are not available for trends in fitness.
Responding to the growing attention on the obesity epidemic, various estimates of the number of deaths attributable to obesity have appeared. They range from 400 000 annually, i.e. about one-sixth of all deaths in the United States, to 112 000 depending on the assumptions and data used.18 The higher number came from a study by investigators including the Director of CDC and thus became known as ‘official,’ whereas the smaller number came from a publication whose senior author was an investigator at the National Center for Health Statistics of CDC.19–21
My reflections on the role of obesity in health, including but not limited to its impact on mortality, are:
- Obesity and overweight should be further studied in their health relationship to physical fitness; thus far, though impressive, the major source of data consists of observation of white, upper-class, men and women attending a fitness centre, whereas we need information about the entire population.
- In the present state of knowledge, programmes intended to deal with overweight and obesity as a health factor should include attention to physical fitness as well as the nutritional aspects of the problem.
- Rather than public health strategies aimed solely at single behaviours such as eating too much, especially harmful kinds of food, or the common sedentary lifestyle, or cigarette smoking, we need to develop an overall strategy for health in the modern world where most people have ready access to the above behaviours. We need, in effect, a new kind of hygiene that applies to our current situation. Of course, we should combat each and all the aspects of living that injure health, but we should emphasize a system of hygiene that deals with the whole group of behaviours that influence health favourably. One study, for example, revealed that following six or seven healthful behaviours reduced not only mortality but also disability among the survivors to about half of that which prevailed among those following only zero-three of the seven behaviours; four or five reduced the zero-three level about one-third.22
- We must combat vigorously those commercial interests that market things that are harmful to health, an approach that has proved its worth in the case of tobacco. Obviously we cannot deal with the food industry in a blanket way, as we have with the tobacco industry, but we must struggle against those elements of the food industry that mislead the public in order to peddle their harmful wares.
- Finally, though obesity and other factors in the epidemiological transition, have thus far affected mainly the currently industrialized world, the chronic diseases and the behavioural factors largely responsible for them are already emerging in the developing world. While public health agencies there must still contend with the communicable diseases, epidemiologists as an element of public health should lead the way toward recognizing and dealing with the epidemiological transition in the developing world.23
 |
References |
|---|
 Top References |
|---|
1 Breslow L. Public health aspects of weight control. Am J Public Health 1952;42:1116–20. (Reprinted Int J Epidemiol 2006;35:10–12.)
2 Breslow L. Chronic disease in the modern public health program. California Health 1947;5:277–80.
3 Commission on Chronic Illness. Chronic Illness in the United States, 4 Volumes. Cambridge, Massachusetts: Harvard University Press, 1957.
4 Moriyana IM, Woolsey TA. Statistical studies of heart disease. Public Health Rep 1951;12:335–68.
5 Dublin LI, Speigelman M. Factors in the higher mortality of our older age groups. Am J Public Health 1952;4:422–29.
6 Dublin LI, Lotka AJ, Spiegelman M. Length of Life. New York: Randal Press, 1949.
7 Morris JN, Heady JA, Raffle PA, Roberts CG, Parks JW. Coronary heart- disease and physical activity of work. Lancet 1953; 265:1053–57.[CrossRef][ISI][Medline]
8 Buechley RW, Drake RM, Breslow L. Height, weight, and mortality in a population of longshoreman. J Chronic Dis 1958;7:363–78.[Medline]
9 New York Metropolitan Life Insurance Company. New weight standards for men and women. Stat Bull N Y Metropol Life Ins Co 1959;40:1–4.
10 Borhani NO, Hechter HH, Breslow L. Report of a ten-year follow-up study of the San Francisco longshoremen: Mortality from coronary heart disease and from all causes. J Chronic Dis 1963;16:1251–66.[CrossRef][ISI][Medline]
11 Paffenburger RS Jr, Laughlin ME, Gima AS, Black RA. Work activity of longshoreman as related to death from coronary heart disease and stroke. N Engl J Med 1970;282:1109–14.
12 Blair SN, Kohl HW III, Paffenbarger RS Jr, Clark DG, Cooper KH, Gibbons LW. Physical fitness and all cause mortality. JAMA 1989;262:2395–401.[Abstract]
13 Blair SN, Kohl HW III, Barlow CE, Paffenbarger RS Jr, Gibbons LW, Macera CA. Changes in physical fitness and all cause mortality. JAMA 1995;273:1093–98.[Abstract]
14 Lee CD, Blair SN, Jackson AS. Cardiorespiratory fitness, body composition, and all-cause and cardiovascular disease mortality in men. Am J Clin Nutr 1999;69:373–80.
15 Barlow CE, Kohl HW III, Gibbons LW, Blair SN. Physical fitness, mortality and obesity. Int J Obes 1995;19 (Suppl 4):S41–44.[ISI]
16 Farrell SM, Braun L, Barlow CE, Cheng YJ, Blair SN. The relation of body mass index, cardiorespiratory fitness, and all-cause mortality in women. Obes Res 2002;10:417–23.[ISI][Medline]
17 National Center for Health Statistics. Health, United States, 2003. Hyattsville, MD: NCHS, 2003.
18 Couzin J. A heavyweight battle over CDC's obesity forecasts. Science 2005;308:770–71.
19 Mokdad AH, Marks JS, Stroup DF, Gerberding JL. Actual causes of death in the United States, 2000. JAMA 2004;291:1238–45 (published correction appears in JAMA 2005;293:293–94).
20 Flegal KM, Graubard BI, Williamson DF, Gail MH. Excess deaths associated with underweight, overweight, and obesity. JAMA 2005;293:1861–67.
21 Mark DH. Deaths attributable to obesity. JAMA 2005;293:1918–19.
22 Breslow L, Breslow N. Health practices and disability: some evidence from Alameda County. Prev Med 1993;22:86–95.[CrossRef][ISI][Medline]
23 Senok AC, Botta GA. Chronic versus acute diseases. Science 2005;309:380–81.
CiteULike 
Connotea 
Del.icio.us What's this?
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||