In a global review of health data from 1980 to 2008, researchers found that health issues which were once thought of as being problems of the rich are now affecting many middle- and low-income populations.
The research was conducted by the World Health Organization in collaboration with several other colleges and institutions, and published in the journal The Lancet.
Researchers speculated that the reasons behind health improvements in high-income countries are largely due to better screening and treatments. They also noted that a shift toward diets that contain healthier fats and lower sodium levels could be the cause.
Rates of disorders like obesity, high blood pressure and high cholesterol have fallen in some high-income countries like the United States but are on the rise in Eastern regions and Southeast Asia.
In North America and Australasia — a region encompassing Australia, New Zealand, New Guinea and nearby South Pacific islands — significant reductions in hypertension rates were observed, while blood pressure was the highest among individuals living in Baltic or East and West African regions.
Total blood cholesterol levels fell for people living in Western countries while those in Asian and Pacific areas showed increased cholesterol levels.
However, the news is not all good for Western regions. Rates of obesity nearly doubled for U.S. residents from 1980 to 2008. Americans also have the highest body mass index in the world.