How your sandwich changed the world

What if you could go back in time and follow your food from the farm to your plate? What if you could see each step of your meal's journey — every ingredient that went into its creation, and every footprint it left behind?

Back in February, The Salt reported on English researchers who did just that: they rigorously investigated the origin of a single loaf of bread, from wheat field to supermarket. Their report is full of incredible detail. How big a field would you need to grow enough wheat for a loaf of bread? Seven square feet. How much fertilizer? About a third of a cup. How much greenhouse gas is released in the creation of a loaf? The equivalent of 1.7 pounds of carbon dioxide.

Now, NPR's science YouTube channel Skunk Bear has tackled a BLT in the same way. Their latest video walks through the myriad steps involved in creating this simple sandwich, drawing on research into the production of bacon, the lettuce, the tomato, and the mayonnaise. Scientists have estimated the carbon footprint for each ingredient.

The video is a reminder that every product we buy or consume has traveled a long way before it enters our lives. By understanding those journeys, and the impact each step has on carbon emissions, we can figure out how to change our own impact on the world.

You can see more from Skunk Bear by subscribing to their YouTube channel. If you have a question you'd like them to tackle, submit it here.