The body mass index in inhabitants of villages in the past 30 years, growing as fast or even faster than their urban counterparts, contrary to popular belief about the connection of urban lifestyle and tendency to overweight, write the authors of a study published in the journal Nature.
The body mass index (BMI) the global average in recent decades is increasing: as shown by previous studies, from 1975 to 2014 in men, BMI standardised for age, rose from 21.7 to 24.2, and women — 22.1 to 24.4. The prevalence of underweight during this period decreased from 13.8 to 8.8 percent for men and 14.6 to 9.7 percent in women, and the prevalence of obesity increased correspondingly from 3.2 to 10.8 and from 6.4 to 14.9 percent.
Ezzati Majid (Majid Ezzati) from Imperial College London and his colleagues from project NCD Risk Factor Collaboration decided to check the popular notion that the increase in BMI and prevalence of obesity associated with the continuing urbanization (as residents of cities higher consumption of fast food and broader access to transport and the types of activities that limit physical activity, as well as a greater bias towards intellectual labour in contrast to the physical). To do this, the researchers analyzed 2009 studies with a total coverage of more than 112 million people from 200 countries.
Scientists have shown that from 1985 to 2017 more than 55 percent of the global increase in BMI was accounted for by rural residents, and in some of the poorer regions and countries with a medium level of income up to 80 percent. The average BMI for women during this time has increased by 2 pounds per square yard for men — 2.2 kilograms per square meter. The average growth in rural areas, for and the other was 2.1, and in the cities — 1.3 and 1.6 kilograms per square meter, respectively. For all regions and groups of people, except for women in the countries of Africa South of the Sahara, BMI in the cities is growing as or slower than BMI in rural areas.
To the output of the study, the researchers prepared a set of interactive visualizations that you can find them here. In, according to the study, men were almost zero difference in BMI between urban and rural residents, but for 30 years it has slightly increased (i.e., became positive). For women small negative difference, on the contrary, became even a little more.
The authors note that, apparently, people in poor rural communities are shifting from undernutrition to poor diet. This, according to them, means that the needs of such communities in healthy food should be given more attention in international programs for the eradication of hunger.