The survey was conducted by the London-based Imperial College and its results were published on May 9 in the international science journal "Nature". The data analysed referred to the height and weight of more than 112 million adults from urban and rural areas in 200 countries in the period from 1985 to 2017.
Every person has an extra 5-6 kilograms of body mass
The survey shows that in the period from 1985 and 2017, the body mass index (BMI) grew on average by 2 kilograms in women and by 2.2 kilograms in men, namely, people covered by the survey had an extra 5-6 kilograms of body mass.
More than half the global increase in obesity in the 33-year period can be ascribed to the growth of BMI in rural areas.
In some low and medium-income countries, rural areas contributed to the total BMI increase with 80%. Since 1985 the average BMI in rural areas has grown by 2.1 kilograms among both men and women, while in urban areas the average BMI in women has grown by 1.3 kilograms and in men by 1.6 kilograms.
This points to astonishing changes that have happened in the last three decades. In more than three-fourths of the surveyed countries, women and men who lived in urban areas in 1985 had a higher BMI than those living in rural areas and over time that difference has changed or has even been reversed in a large number of countries.
In the high income countries, the increase in the body mass in rural areas was evident especially among women, and experts attribute this to shortcomings of life outside urban areas - a lower income and lower level of education, limited availability and higher prices of healthy food products, and fewer sports and recreational facilities.
In the period from 1985 to 2017, rural areas in lower and medium-income countries saw an increase in income, improvement of infrastructure, development of agricultural equipment and an increase in the number of cars, which has resulted in less energy consumption but also greater consumption of processed food products and products of lower quality due to lack of adequate legislation. These factors contribute to a faster increase in BMI in rural areas.
BMI higher in all countries
In the 1985-2017 period, BMI dropped mildly among women in 12 countries in Europe - Greece, Spain, Lithuania, the Czech Republic, Italy, Portugal, Serbia, France and Malta - and in Asia Pacific - Nauru, Singapore and Japan.
Conversely, BMI among women grew by 5 kilograms in Egypt and Honduras.
BMI grew in all countries, and the highest increase, of more than 3.1 kilograms, was reported in Saint Lucia, Bahrain, Peru, China, the Dominican Republic and the USA.
Women living in the rural areas of Central and East Europe had, on average, a body mass that was around one kilogram higher than that of women in urban areas, and the increase was reported in Belarus, the Czech Republic and Latvia. That difference has remained almost unchanged since 1985.
In men from rural areas, the greatest difference was recorded in Sweden, the Czech Republic, Ireland, Australia, Austria and the USA. Men in rural areas had a BMI that was around 0.35 kg higher that that of men in urban areas.