It's been a long day at work. You're beat. You're hungry. The kids are hungry. And you're just short of the ingredients you need to make a decent dinner. So the hell with it — you run down the street and get some burgers and fries. Millions of Americans do exactly that every week, sometimes twice or more.
An increasing amount of the world's population is consuming this type of diet and the cumulative impact is proving to be devastating to human health and the environment.
University of Minnesota researchers have published a study in the journal Nature, looking at the dietary habits of people in developing countries, where meat, refined sugars, and processed foods are becoming a bigger share of their diets. The team's findings not only point to higher rates of diabetes, heart disease, and some cancers but also suggest that carbon emissions from agricultural production could nearly double by 2050.
The report shows that rising incomes are matched by increased meat consumption and higher intake of refined sugars, fat, and alcohol. China's consumption of meat jumped from a per capita average of barely two grams a day in 1961 to nearly 25 grams in 2009 as per capita GDP grew from barely $1,000 to about $7,500, the study says. For a group of nations including Brazil, South Africa, Turkey, and Iran, both meat consumption and income roughly tripled over the same period.
"A lot of the countries that are in the sort of rapidly developing phase, especially in Asia, are about halfway up this curve," David Tilman, lead author, told VICE News.
Tilman said that in countries like China, India, and Malaysia, people are moving to cities from rural villages, where their diets were largely made up of grains, fruits, and vegetables.
"They left that behind when they took a job in a factory, and now they're working literally 10 to 12 hours a day, seven days a week in many of these developing countries," he told VICE News. At the end of those days, he says, prepared food — cheap, full of starches, fat, and sugar — are readily accessible.
"They just follow their taste buds, and these things taste wonderful," he said.
In China, the share of the population suffering from Type 2 diabetes grew from less than one percent in 1980 to 10 percent in 2008. More than two billion people worldwide are now overweight or obese.
And the rise of meat consumption means more grain needs to be grown to feed ever expanding herds of livestock.
'You can be a vegetarian and have a horrible diet.'
"It takes a cow 20 pounds of protein from plants to get one pound of their own protein that we can eat," Tilman told VICE News. "So basically, we have to grow 20 times more crop to be able to eat the beef we want, as opposed to eating the grains we grow."
For chicken and pork, the average is about 5-to-1 — still a big multiplier, said Tilman.
An estimated two million square miles of cropland globally would need to be cleared by mid-century to satisfy the world's growing demand for meat, pork, and poultry. The result is greater amounts of habitat destruction and more mechanized farming, along with more frequent use of pesticides and fertilizers, which are among the leading sources of water pollution worldwide. At sea, mechanized trawling is expected to replace traditional fishing techniques, putting fisheries at risk of collapse and damaging sensitive aquatic ecosystems.
Based on current trends, Tilman estimated, the amount of greenhouse gases released by agricultural production could jump by 1.8 billion tons a year — a figure comparable to all carbon emissions from cars, trucks, and planes in 2010. The United Nations estimates a fifth of global greenhouse gas emissions come from the agricultural sector. The study concludes that by 2050 these dietary trends, if unchecked, will be "a major contributor" to an estimated 80 percent increase in greenhouse gas emissions from food production.
University of Michigan's Martin Heller, who has undertaken similar research on diets in America, said feed commodities, like corn, are heavily subsidized in the US. Those subsidies mask the true cost of beef.
Making matters worse, he said, up to 30 percent of US-produced food items go into the garbage rather than someone's stomach. "That ends up being about a third of the carbon footprint of a meat-based diet," Heller told VICE News.
The study found that although these changes in eating habits are causing globally significant increases in carbon emissions and contributing to land clearing, consumers in developing countries can avoid those outcomes if they shift toward less meat-intensive diets.
Tilman said the trend toward eating more meat has been slower in India, where religious and cultural norms emphasize vegetarianism. But India is still seeing an increase in diabetes as sugary and starchy foods become more common.
"You can be a vegetarian and have a horrible diet," he said.
If everyone on Earth became a vegetarian, the study says, levels of farm-related emissions would drop by 55 percent from their projected 2050 levels. Diets where fish is the only animal protein consumed cut the 2050 estimate by 45 percent, while a Mediterranean diet — one high in seafood, fruits and vegetables, with beef, lamb, poultry, or pork consumed in moderation — cuts the emissions level by 30 percent. Those diets also have the advantage of reducing the risk of heart disease and other illnesses.
"I think that some governmental policies and educational programs in developing nations as they undergo this transition could make a big, big difference in the health of their citizens, and it really lowers the costs," Tilman told VICE News. "Diet is one solution. Having much more efficient farming is another big part of it."
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