Background and objective:Obesity is going to become a serious public health problem around world in the 21st century. Over recent years, the obesity prevalence rates in Taiwan have been on the rise every year. The changes shown by the results of “2005-2008 Nutrition and Health Survey In Taiwan” and “1993-1996 Nutrition and Health Survey in Taiwan” suggested the prevalence rates of mild obesity (BMI≧27) and moderate-to-severe obesity （BMI≧30）among the adults in Taiwan have increased respectively from 8.1% and 2.4% to 13.0% and 6.0%. Obesity is closely related to many death-causing diseases. This study was conducted based on data obtained from “the Survey of the Health Status of the Middle-aged and the Elderly in Taiwan” to examine the cohort effect of the social changes and obesity prevalence experienced by the elderly born before the first half of the 20th century.
Study Method:In this study data such as heights and weights from “the Survey on the Health and Living Status of the Middle-aged and the Elderly in Taiwan” conducted from 1989, 1999 and 2007 were used to examine the changes in obesity prevalence rates among the elder people of difference birth cohorts in Taiwan. Birth cohorts were converted into dummy variables to analyze their influence on obesity prevalence rates using logistic regression analysis.
Study results:The study found that there were obvious differences in the obesity conditions among the seniors of different birth cohorts in Taiwan. In terms of underweight prevalence (BMI<18.5), the “obesity” prevalence rates among the senior citizens aged 70-74 in 1989 (born in 1915-1919), those aged 70-74 in 1999 (born in 1925-1929) and those aged 68-72 in 2007 (born in 1935-1939) went down from 12.3% to 7.0% and then to 4.0%. In terms of obesity prevalence (BMI>27.0), the obesity prevalence rates among the elders aged 60-64 in 1989 (born in 1925-1929), those aged 60-64 in 1999 (born in 1935-1939), and those aged 58-67 in 2007 (born in 1940-1949) went up from 11.9% to 17.0%, and then to 20.5%-21.2%. Moreover, obesity rates would increase with age, and then might decrease after a certain age. Besides, it was found that the obesity rates among females and mainlanders (those who relocated to Taiwan from China after 1948) were higher compared with other communities and there was a lower obesity rate among those who had received education for longer than 10 years.
Conclusion and suggestions:The results of the study suggested that there were significant changes in the nutrition and living standards of senior citizens of different birth cohorts. There were less and less underweight seniors of later birth cohorts, but overweight and obesity have become more and more common. Consequently, the prevention of obesity has now become a task of great urgency to the elderly in Taiwan.
