A simple change could massively reduce the negative impact of most people's diets: swapping beef for poultry.
It doesn't often make the headlines, but food production is one of the major culprits of climate change, contributing up to 29% of total greenhouse gas emissions. Out of this, meat takes an overwhelming slice of the pie.
At a basic level, it's easy to understand why meat is so inefficient: plants convert around 10% of the energy they receive into edible nutrients. Animals have a similar rate: only about 10% of the plants they eat are converted into something we can eat, so 90% of the energy is wasted (arguably, some of that energy comes from plants we ourselves couldn't eat, but even so, it's a wasteful process).
Over 50% of all the emissions associated with food comes from meat production and consumption, although meat itself provides less than 10% of the calories we eat. Beef, in particular, is extremely inefficient.
A beef with the environment
It takes 75 times more energy to produce a pound of beef than to produce a pound of corn, and beef also requires 54 calories of fuel to produce 1 calorie of protein, compared to 2-3 calories of fossil fuel for 1 calorie of soy or wheat. Study after study has shown that beef is an important contributor to global greenhouse gas emissions -- and this one is no different. In the latest research, scientists show that even by replacing beef with other meat (poultry) it could make a big difference.
Diego Rose, a director of nutrition at Tulane University, analyzed what would happen if people would substitute a beef-focused meal with a similar poultry meal. Along with his colleagues, he analyzed the diet information from more than 16,000 participants in the 2005-2010 National Health and Nutrition Examination Survey, calculating a carbon footprint of all diets.
They found that the 10 foods with the highest impacts on the environment were all cuts of beef.
Then, they looked at what would happen if all beef in the diets would be replaced by an equivalent poultry dish. For instance, broiled beef steak was replaced with broiled chicken and ground beef with ground turkey. The results were impressive.
"Our simulation showed that you don't have to give up animal products to improve your carbon footprint," Rose commented on the study. "Just one food substitution brought close to a 50% reduction, on average, in a person's carbon footprint."
That's how disproportionate beef's carbon footprint is -- even replacing it for something that's not exactly eco-friendly either has a massive impact. Of course, any further reduction of meat consumption has even more environmental benefits. Researchers also stress that food waste and overeating also increase the carbon footprint of our diet.
The results have not yet been peer-reviewed but have been presented at the Nutrition 2019 conference, where they have been selected by a panel of experts.