The worldwide prevalence of DM has risen dramatically over the past two decades. Although the prevalence of both type I and type 2 DM is increasing worldwide, the prevalence of type 2 DM is expected to rise more rapidly in the future because of increasing number of people with obesity due to reduced activity levels. DM increases with aging. However it has recently become prevalent among children and teenagers especially in the U.S.A.
An article published in pubmed website shows that American Indians of all ages and both sexes have a high prevalence of obesity. The health risks associated with obesity are numerous and include Type 2 diabetes mellitus, hypertension, dyslipidemia and respiratory problems. Obesity has become a major health problem in American Indians only in the past few generations and it is believed to be associated with the relative abundance of high-fat, high-calorie foods and the rapid change from active to sedentary lifestyles.
The authors of the article reviewed selected literature on prevalence of obesity in American-Indian children and health consequences of obesity.
Obesity is now one of the most serious public health challenges facing American-Indian children and it has grave implications for the immediate and long-term health of American-Indian youth. Unless this pattern is reversed, American-Indian populations will be burdened by an increased incidence of chronic diseases. Intervention studies are urgently needed in American-Indian communities to develop and test effective strategies for obesity prevention and treatment.
The authors conclude to be effective, educational and environmental interventions must be developed with full participation of the American-Indian communities.
Also in Iran and many other countries, the rate of obesity in young population has recently increased remarkably. The gene of obesity is inherited from parents and thus its health consequences are threatening the current young generation.
In 2000, the prevalence of DM was estimated to be 0 .19% in people below 20 years of age and 8 .6% in people more than 20. In individuals older than 65 years, the prevalence of DM was 20.1 %. The prevalence is similar in men and women throughout most age ranges but is slightly greater in men >60 years.
W.H.O. the world health organization estimated 170,000,000 diabetics in the year 2000 world over. It says the number will reach 330,000,000. There is considerable geographic variation in the incidence of both type I and type 2 DM. Scandinavia has the highest incidence of type 1 DM (e .g ., in Finland, the incidence is 35/100,000 per year) .
The Pacific Rim has a much lower rate (in Japan and China, the incidence is 1 to 3/100,000 per year) of type 1 DM ; Northern Europe and the United States share an intermediate rate (8 to 17/100,000 per year) .
Much of the increased risk of type I DM is believed to reflect the frequency of high-risk HLA alleles among ethnic groups in different geographic locations. The prevalence of type 2 DM and its harbinger, IGT, is highest in certain Pacific islands, intermediate in countries such as India and the United States, and relatively low in Russia and China.
This variability is likely due to genetic, behavioral and environmental factors. DM prevalence also varies among different ethnic populations within a given country. In 2000, the prevalence of DM in the United States was 13% in African Americans, 10 .2% in Hispanic Americans, 15.5% in Native Americans (American Indians and Alaska natives), and 7 .8% in non-Hispanic whites. The onset of type 2 DM occurs, on average, at an earlier age in ethnic groups other than non-Hispanic whites.