A once quintessentially American disease has become a global pandemic. Obesity and the diseases that come with it – diabetes, hypertension and heart disease – are finding new frontiers in the developing world.

The US spends roughly $150 billion a year on obesity and associated diseases. Most countries don’t have that kind of money to spend: people will either go untreated or health budgets will be strained.

In richer countries diabetes is a manageable disease. However, as an endocrinologist put it recently in The New York Times, elsewhere on the globe ‘patients often lack access to care and can’t get insulin, blood-pressure pills and other medicines that diminish the risk of complications. As more and more people develop the disease, hospitals may soon be overrun with patients experiencing all of its worst outcomes: blindness, limb amputation, kidney failure (necessitating dialysis), coma and death.’

While the US government likes to brag about its foreign aid, it has played a large role in creating an obesity crisis in poorer countries that will saddle their health budgets with billions of dollars of extra spending.

America’s public-health crisis hasn’t stopped Taco Bell from a prolonged advertising campaign urging people to consume a fourth meal; however, at this point, the US market is so saturated that it is difficult to sell Americans more junk food than they’re already eating.

Therefore, the junk food oligopoly is looking to push their products onto the Majority World.

All the way back in 2005, Mark Berlind, executive vice-president for global corporate affairs at Kraft, testified before the US senate: ‘The 50 US states are currently Kraft’s largest market. Given US demographic realities, however, future growth for Kraft – as well as for the entire US food and agriculture complex – is inextricably tied to our ability to access export markets. Mr Chairman, as you and most other farm state members know, 95 per cent of the world’s consumers live outside the US. That is where future growth will take place.’

The US is exporting the worst of its eating habits to once-healthy countries and traditional diets have been supplanted by globalization. According to the medical journal The Lancet, 70 per cent of adult women and nearly 40 per cent of men in South Africa are overweight or obese.

Meanwhile, in the Gulf region, Business Week refers to America’s gastronomic influence as ‘the other Gulf-war syndrome’. When thousands of US troops were stationed in Kuwait, fast-food outlets followed them there. Today, Kuwait, alongside its neighbours Saudi Arabia, Bahrain, the United Arab Emirates and Qatar, is one of the fattest countries in the world.

Places as far-flung as the Marshall Islands (where diabetes takes up 25 per cent of healthcare expenditure) and Samoa are also home to some of the most morbidly obese populations on the planet.

Since the implementation of the North American Free Trade Agreement (NAFTA) in 1994, Mexicans, too, have ballooned in size. According to a study by the Institute for Agriculture and Trade Policy, this is no coincidence. Trade liberalization has facilitated a significant change in Mexico’s food consumption patterns, which has resulted in a decline in public health. Mexico is now the highest consumer of soft drinks per capita in the world (163 litres per year) while many people in the country lack access to potable water. Indeed, soft drinks are often cheaper than bottled water.

Of course, the soft-drink market is dominated by US-based companies. Exports of high-fructose corn syrup from the US have massively increased and NAFTA has also led to a greater flow of ready-to-eat calorific processed snack food into Mexico and the expansion of US fast-food restaurant chains.

KFC, for example, is seeking to expand across Africa. Similarly, as The Guardian reports, ‘Nestlé is using a floating supermarket to take its products to remote communities in the Amazon. Unilever has a small army of door-to-door vendors selling to low-income villages in India and west and east Africa. The brewer SABMiller, as a leading Coca-Cola bottler and distributor, is aiming to double fizzy-drink sales in South African townships.’ America’s ‘obesogenic’ environment is becoming a global norm.

A 2004 article in the American Journal of Clinical Nutrition found that for $1 spent in a supermarket, an American could buy either 1,200 calories of unhealthy processed food or 250 calories’ worth of carrots, 875 calories of soda or just 170 calories of fruit juice. Why are nutrient-poor, energy-dense foods so much cheaper?

The agriculture lobby is a powerful force in the US and it has used its influence on government to create some perverse agricultural policies. A 2013 report by the US Public Interest Research Group, ‘Apples to Twinkies: Comparing Federal Subsidies of Fresh Produce and Junk Food’, found that since 1995, high-fructose corn syrup, corn-starch and soy oils (all commonly used in junk food) have been subsidized by the US taxpayer to the tune of over $19 billion, without an equivalent subsidy for fruit and vegetables.

The resulting cheap junk products are exported throughout the world.

Obesity now kills more people worldwide than hunger, but the political response couldn’t be more different: while emaciated bodies elicit calls to do something, the obesity crisis induces diatribes against the ‘nanny state’. The government, we are told, shouldn’t meddle in our lives. Meanwhile, corporations are free to meddle as much as they want – to subject us to manipulative, pervasive and sophisticated marketing.

The US spends untold sums on the war on drugs, yet junk food kills more people than crack cocaine and heroin combined. Billions of dollars and whole careers are spent researching cures for diseases, yet today’s biggest problem is an ailment humanity has inflicted upon itself.