November 14, 2014
Fish And Vegetable Diet Could Save The Planet As Well As Our Lives
John Hopton for redOrbit.com - Your Universe Online
A new study from the University of Minnesota has investigated the joint health and environmental impact of dietary habits, and found that changes to a healthier, Mediterranean-style diet would be of benefit to the planet as well as to our own life expectancy.Consumption of refined sugars, refined fats, oils and red meats such as beef, which have increased as cities and incomes have grown and are expected to do so further in the future, has long been known to be detrimental to health and a contributing factor in type II diabetes, heart disease and some cancers. More people are now aware of the need for a better diet, but major trends have not been reversed. The impact of these types of diets on the environment has until now been less publically discussed.
The study, led by ecologist David Tilman with graduate student Michael Clark and published in the November 12 online edition of the journal Nature, synthesized data on environmental costs of food production, diet trends, relationships between diet and health, and population growth. It concluded that a fish-based diet (pescatarian diet) or a vegetarian diet could reduce greenhouse gas emissions and protect the habitats of endangered species, over “resource- and land-intense agricultural products” like beef.
“We showed that the same dietary changes that can add about a decade to our lives can also prevent massive environmental damage,” said Tilman, a professor in the University’s College of Biological Sciences and resident fellow at the Institute on the Environment. “In particular, if the world were to adopt variations on three common diets, health would be greatly increased at the same time global greenhouse gas emissions were reduced by an amount equal to the current greenhouse gas emissions of all cars, trucks, planes, trains and ships. In addition, this dietary shift would prevent the destruction of an area of tropical forests and savannas as large as half of the United States.”
The researchers looked at incomes between 1961 and 2009 and found that people consumed more meat protein, empty calories (food that adds to the calorie total but contains little or no nutrition) and total calories per person. When this income growth was taken with predicted population growth, the study found that diets in 2050 would contain fewer servings of fruits and vegetables, but about 60 percent more empty calories and 25 to 50 percent more pork, poultry, beef, dairy and eggs. Using life-cycle analyses of various food production systems, the researchers also calculated that these 2050 diets would lead to an 80 percent increase in global greenhouse gas emissions from food production as well as habitat destruction due to land clearing for global agriculture.
As the University of Minnesota statement explains, “The authors acknowledged that numerous factors go into diet choice, but also pointed out that the alternative diets already are part of the lives of countless people around the world.” Tilman and Clark stressed that the multiple benefits of improved dietary habits should be seriously considered, concluding that, “the evaluation and implementation of dietary solutions to the tightly linked diet-environment-health trilemma is a global challenge, and opportunity, of great environmental and public health importance.”
No mention was made of the potential impact of a global shift from meat to fish on already overfished waters and on traditional fishing communities whose livelihoods have been significantly affected by existing numbers of industrial fishing trawlers.