“Over the past 40 years, we have changed from a world in which underweight prevalence was more than double that of obesity, to one in which more people are obese than underweight,” explains senior author Professor Majid Ezzati from the School of Public Health at Imperial College London, London, UK. “If present trends continue, not only will the world not meet the obesity target of halting the rise in the prevalence of obesity at its 2010 level by 2025, but more women will be severely obese than underweight by 2025.”
The study researchers estimated trends in mean BMI and in the prevalences of a complete set of BMI categories for adults in 200 countries, as well as calculating the probability of meeting the target of halting by 2025.
They found that the largest increase in men’s mean BMI occurred in high-income English-speaking countries and in women in central Latin America. In 2014, men and women in high-income English-speaking countries had substantially higher BMIs than those in continental Europe, whereas in 1975 their BMI had been similar or lower, especially for women.
They also reported that in 2014, more men were obese than underweight in 136 (68%) of 200 countries; in 113 of these countries, more men were severely obese than underweight. For women, obesity surpassed underweight in 165 (83%) countries and severe obesity surpassed underweight in 135 countries.
Obesity prevalence was less than 1% in men in Burundi and Timor-Leste and 1–2% in another 15 countries in central, east, and west Africa and in south and southeast Asia. The lowest prevalences in women were in Timor-Leste, Japan, Vietnam, North Korea, Cambodia, Laos, and Bangladesh, all less than 5%. In comparison, more than 45% of men in six island nations in Polynesia and Micronesia, and more than 50% of women in 11 such island nations were obese. The prevalence of obesity in women in several Caribbean and Middle Eastern countries was 40–50%. Severe obesity surpassed 20% in men and 30% in women in some Polynesian and Micronesian islands, reaching 33·4% in American Samoa in 2014. More than 15% of women in Nauru and American Samoa were morbidly obese.
In 2014, about 266 million men and 375 million women were obese in the world, compared with 34 million men and 71 million women in 1975. In 2014, 58 million men and 126 million women were severely obese. High income English-speaking countries and these countries contained the largest share of the world’s severely obese people (27·1%; 50 million), followed by 13·9% (26 million) in the Middle East and North Africa.
Country by country BMI and rankings available below – highlights include:
- Women in Singapore, Japan, and a few European countries including Czech Republic, Belgium, France, and Switzerland had virtually no increase in average BMI (less than 0.2 kg/m² per decade) over the 40 years.
- Island nations in Polynesia and Micronesia have the highest average BMI in the world reaching 34.8 kg/m² for women and 32.2 kg/m² for men in American Samoa. In Polynesia and Micronesia more than 38% of men and over half of women are obese.
- Timor-Leste, Ethiopia, and Eritrea have the lowest average BMI in the world. Timor-Leste was the lowest at 20.8 kg/m² for women and Ethiopia the lowest at 20.1kg/m² for men.
- More than a fifth of men in India, Bangladesh, Timor-Leste, Afghanistan, Eritrea, and Ethiopia, and a quarter or more of women in Bangladesh and India are still underweight.
- Among high-income English-speaking countries, the USA has the highest BMI for both men and women (over 28 kg/m²). More than one in four severely obese men and almost one in five severely obese women in the world live in the USA.
- Men in Cyprus, Ireland, and Malta (27.8 kg/m²), and women in Moldova (27.3 kg/m²) have the highest average BMI in Europe. Bosnian and Dutch men (both around 25.9 kg/m²) and Swiss women (23.7 kg/m²) have the lowest average BMI in Europe.
- The UK has the third highest average BMI in Europe for women equal to Ireland and the Russian Federation (all around 27.0 kg/m²) and tenth highest for men along with Greece, Hungary, and Lithuania (all around 27.4 kg/m²).
- Almost a fifth of the world’s obese adults (118 million) live in just six high-income English-speaking countries—Australia, Canada, Ireland, New Zealand, UK, and USA. Over a quarter (27.1%; 50 million) of the world’s severely obese people also live in these countries.
- By 2025, the UK is projected to have the highest levels of obese women in Europe (38%), followed by Ireland (37%) and Malta (34%). Similar trends are projected in men, with Ireland and the UK again showing the greatest proportion (both around 38%), followed Lithuania (36%). By comparison, 43% of US women and 45% of US men are predicted to be obese in 2025.
“To address this problem will require social and food policies that enhance food security in poor households, but also avoid overconsumption of processed carbohydrates and other unhealthy foods,” the authors write. “Second, although adiposity has been consistently shown to be an independent risk factor for several NCDs in individual-level epidemiological studies, at the population level, the effect of rising BMI on the course of mortality reduction has so far been somewhat small in high-income countries, possibly because pharmacological treatment has helped reduce blood pressure and serum cholesterol and manage diabetes complications, which are mediators of the effects of BMI on cardiovascular diseases.”
Writing in a linked Comment, Professor George Davey Smith from the MRC Integrative Epidemiology Unit, School of Social and Community Medicine, Bristol, UK discusses “a fatter, healthier but more unequal world”. He points out that although in high income countries obesity is a major and growing problem, under-nutrition in low income countries remains a major health issue, including for the offspring of seriously under-weight women. He writes, “A focus on obesity at the expense of recognition of the substantial remaining burden of undernutrition threatens to divert resources away from disorders that affect the poor to those that are more likely to affect the wealthier in low income countries.”
“Even antihypertensive drugs, statins, and glucose lowering drugs will not be able to fully address the hazards of such high BMI levels, and bariatric surgery might be the most effective intervention for weight loss and disease prevention and remission,” they write. “However, long-term health outcomes of bariatric surgery are largely unknown and it is not accessible to most people in low-income and middle-income countries because of financial and health system barriers.”
To access this paper, please click here