The World is Fat: the Overweight Now Outnumber the Undernourished

“Worldwide, more than 1.3 billion people are overweight, whereas only 800 million are underweight – and these statistics are diverging rapidly.” – Barry M Popkin

For most developing nations, obesity has emerged as a more serious health threat than hunger. Although under-nutrition and famine remain significant problems in sub-Saharan Africa and South Asia, even desperately poor countries such as Nigeria and Uganda are wrestling with the dilemma of obesity.

Globalisation over the past 20 years has contributed to the increased consumption of sweetened beverages, vegetable oils and animal-source foods by poor people in developing countries, as they also adopt sedentary Western lifestyles. This combination of lifestyle and dietary changes is paving way for a global public health catastrophe.

Obesity is a burden on the poor

In 1989 fewer than 10% of Mexicans were overweight, nobody talked about obesity and diabetes were almost nonexistent. National surveys in 2006 found that 71% of Mexican women and 66% of Mexican men were now overweight or obese, with almost 1/7th of the country bearing the burden of type 2 diabetes. Incidentally, Mexicans have since surpassed the US as the world’s number 1 Coca-Cola drinkers per capita.

In the developing world, obesity has become predominantly a problem of the poor, just as it is in the US. In all countries with a GDP greater than US$2,500 per capita (which includes most developing nations outside of sub-Saharan Africa) obesity rates are higher for poor women than for those with higher socioeconomic status.

As average incomes have risen, farm labourers and the urban poor have adopted modern habits associated with obesity such as watching television and shopping in supermarkets, but lack access to education, healthier foods and recreational opportunities.

Scientists have also long hypothesised that Latin American, African and South Asian populations carry more “thrifty genes” that may predispose the obese in these developing countries to develop diabetes or high blood pressure than obese individuals of European descent. In China, where obesity levels are climbing rapidly, nearly one third of the population suffers from high blood pressure.

A sickly sweet disaster

One of the biggest contributors to the obesity epidemic in the Third World is the recent popularity of sweetened beverages. The proportion of calories coming from beverages has been relatively small until the past 50 years, when Coca-Cola, Pepsi and other soft drinks began spreading across the globe. The human body did not evolve to reduce food intake to compensate for beverage consumption, therefore people continue to eat the same amount of food and their total calorie consumption increases.

Research has estimated sweeteners in beverages added about 137 kcal to the average American diet between 1977 and 2006, which translates to an average weight gain of 6.4 kgs over a year. The average Mexican now consumes more than 350 kcal from beverages every day.

The expansion of supermarkets in the developing world has greatly increased the availability of cheap sweetened beverages and processed foods. Technological advances in production and processing have made vegetable oil a relatively cheap option for poor families. The consumption of energy-dense vegetable oils (soybean oil, palm oil, corn oil and their variations) has recently skyrocketed in the developing world. In China, the average daily vegetable oil intake rose from 14.8 grams per person in 1989 to 35.1 grams per person in 2004, adding an extra 183 kcals to the daily diet; the poor spend a larger share of their food expenditures on vegetable oil than the rich.

The globalisation of obesity

The overarching trend that is encouraging all these detrimental changes in diet and lifestyle is globalisation. Global food retailers are opening cheap megastores, global media companies have enhanced the attraction of television and the marketing of sugar-loaded foods and beverages. Many governments and industries are contributing to the growth in obesity by flooding developing countries with cheap sweeteners, oils and meat while doing nothing to promote the consumption of fruits and vegetables. Furthermore, international agencies such as the World Bank have promoted agricultural changes that have encouraged the proliferation of unhealthy diets in the developing world.

The long-held philosophy of agricultural experts is that once a country produces enough grains and tubers, it should massively subsidise its livestock, poultry and fish industries. The result has been a major reduction in the prices of animal-source foods.

Over the past 20 years most of the growth in the world’s production of meat, poultry, fish, eggs and milk has come from developing nations. Latin Americans are eating more beef, Chinese are eating more pork, and Indians consuming more dairy products. By 2020 developing countries are expected to produce nearly two thirds of the world’s meat and half its milk.

People are rapidly abandoning their traditional low-fat, high-fibre diets and switching to meals of calorie-rich fats, sweeteners and refined carbohydrates.

The need for a globalised solution

Representatives of the food industry insist that governments should not restrict an individual’s dietary choices, their solution is to teach people how to control their diets and become more physically active (ed: ironically these companies spend billions of advertising dollars on television). Even most health professionals in the US and abroad focus on the narrow, short-term need to educate children and their parents. But this strategy ignores the vast social, technological and structural changes that are pushing millions of people into debilitating lives of obesity. If left unchecked, the momentum of these changes will cause horrendous increases in chronic illness and reductions in life expectancy worldwide.

Government and private aid programs in developing countries can also backfire if national hunger programs do not consider the consequences of transitioning their populations to unhealthy and overweight lifestyles.

The need for healthier, sustainable agriculture

We could begin by restructuring the massive agricultural subsidies that encourage the production of meat, poultry and dairy products. Instead of giving billions of dollars to giant agribusinesses growing grain for livestock, the US and other high-income nations could direct some of that money to farmers cultivating fruits and vegetables.

Reforms are needed to make healthier diets available and affordable for poor people in developing countries (and developed countries). Current food prices do not take into account the health and environmental costs of their production and consumption. Making meat more expensive and vegetables cheaper would provide an incentive for healthier food choices. New farm policies should also promote the global consumption of whole grains, which have more fibre, vitamins and minerals than refined carbohydrates.

Government responsibility is our responsibility

Revamping farm subsidies will not be as effective for discouraging the consumption of sweetened foods and beverages, because the cost of sweeteners represent just a small fraction of their price. The author of this research, professor Barry M Popkin, is working with the Ministry of Health in Mexico to devise taxes on caloric sweeteners and other high-calorie beverages. Working with the Chinese government in testing a tax on vegetable oil, he has found that taxing dietary fat can cut the total calorie intake while increasing protein consumption among the poor in China, because they substitute healthier foods for the fats.

Understanding the wider global, socioeconomic, environmental and agricultural issues driving the obesity epidemic will help all health professionals to design more effective weight-loss programs. No country in modern times has succeeded in reducing the number of its citizens who are overweight or obese and the obesity epidemic is accelerating. Gathering political support for a fight against obesity remains difficult when obesity is still viewed as a sigh of sloth and gluttony rather than as a consequence of global changes. With this knowledge, we all have the responsibility to support policies that can stem this truly globalised epidemic.


  • Popkin BM. 2007. The world is fat. Scientific American Magazine, 88-94, Sept.
  • Monteiro CA, Moura EC, Conde WL, Popkin BM. Socioeconomic status and obesity in developing countries: a review. Bulletin of the World Health Organisation. 2004;82:940-946. [PDF]
  • The Nutrition Transition []


Jinnan Cai from Clinical Nature