Our Tropical Future: A new report on the State of the Tropics has revealed rapid changes in human and environmental health in the Earth’s tropical regions. This is the second in a four-part series about the new report, based on the work of 12 universities and research institutions worldwide, which shows the challenges facing diverse nations such as Burma/Myanmar to manage those changes.
If you’re looking for a good news story about the health of the world, then consider taking a trip to the Tropics.
An end to world poverty is still a long way off, but poverty is falling in the Tropics. Among people living in the 130-plus tropical nations and territories, shown below, the proportion living in extreme poverty has almost halved since the 1980s.
The rates of infectious diseases are also declining, along with maternal and child mortality rates. Life expectancy is on the rise.
All of those trends for the better have global significance, given that by 2050 three out of every five children will be living in a tropical part of the world.
However, it’s not all good news on human health, according to the inaugural State of the Tropics Report, launched this week by Nobel Prize winner Aung San Suu Kyi in Myanmar.
As more people have emerged from poverty, obesity is on the rise, increasing even faster than global trends. And with it comes a growing burden of non-communicable diseases like cardiovascular disease, diabetes and cancer.
Even with poverty falling, 99% of the tropical population today still live in a low- or middle-income nation. Rates of infectious diseases are still much higher in the Tropics, leading to a new and debilitating double burden of infectious and non-communicable diseases in many nations.
The coming generations of children in the Tropics are likely to be wealthier, but we clearly need to do more to give them a better chance at growing up healthier than before.
Emerging from poverty into a new world
The State of the Tropics Report highlights two particularly important region-wide trends in human health.
The first is significant progress across a range of social determinants of health, including poverty. The proportion of the tropical population living in extreme poverty dropped from 51% in 1981 to 28% in 2010.
Along with the improvements already mentioned in infectious diseases, maternal and child mortality rates and life expectancy, there are a number of causes for optimism.
However, the other important region-wide trend is more worrying.
Obesity rates are increasing at an alarming rate. Between 2002 and 2010, the proportion of obese adults in the Tropics jumped from 4.4% to an estimated 6.8%. That’s an average annual growth rate of 5.5%.
Compare that with the global obesity increase from 10% of the population in 2002 to 12.8% in 2010 (a growth rate of 3.6%).
Within the Tropics, there is huge regional variation.
The greatest increases occurred in Central America (23.1% to 31.6%), the Caribbean (14.7% to 22.9%) and South America (13.9% to 21.4%).
In Oceania, the island nations of Samoa, Tonga and Micronesia had obesity rates of 51%, 71% and 72% respectively in 2010. These are the highest national rates in the world. The obesity crisis in some regions in the Tropics has already reached epidemic proportions – and the problem across the Tropics is growing fast.
‘The new smoking’
Obesity – defined as a body mass index greater than or equal to 30 – has been dubbed “the new smoking”.
Although long recognised as a major risk factor for cardiovascular disease, cancer, diabetes, osteoarthritis, chronic kidney disease and dementia, obesity has received little attention as a threat worthy of grass-roots change. Action to address it is still sporadic and disconnected.
The new Global Burden of Disease Study has shone new light on the scale and complexity of the problem.
There has been a remarkable increase in the proportion of children and adolescents who are overweight or obese. In developed nations, nearly one in four children was overweight or obese by 2013, while in developing nations the proportion has risen to more than one in eight children. And in the past 33 years, no countries have reported success in reducing obesity rates.
However, a few communities have produced some small signs of progress. In the United States, for example, a raft of initiatives to promote healthy eating and greater physical activity in the state of Mississippi saw obesity fall among some schoolchildren.
And in Oklahoma City, which had been ranked as one of America’s fattest cities, residents collectively lost half a million kilograms over five years, as a result of a redesign based on promoting physical activity: towards a city for people, not cars. By 2012, it had become one of the USA’s fittest cities.
Raising tomorrow’s children
Based on median population growth and life expectancy assumptions, by 2050 the Tropics will be home to 60% of the world’s children under 10 years old. Half of these children will live in the tropical region of Central and Southern Africa, shown on this map.
There is cause for both optimism and concern about those children’s future.
On the one hand, poverty and rates of infectious diseases are decreasing. On the other, increasing obesity rates will fuel growth of non-communicable diseases worldwide, which already disproportionately affect low-and-middle-income nations.
And despite significant progress over the past few decades, infectious diseases and under-nutrition, to which children are particularly vulnerable, remain major public health concerns. This places a huge burden on already fragile health systems and budgets especially in tropical nations.
Like developing nations worldwide, many nations in the Tropics are witnessing the co-existence of under-nutrition and obesity within their borders, and even within the same household.
Giving those children a brighter future will require new ways of delivering health care that match the changing disease profile. And it will require new approaches to tackling the complex causes of obesity.
There are small signs, at least in some parts of the USA, that progress can be made to reduce obesity levels. It’s time to adapt some of these solutions to improve health in our tropical neighbourhoods.