We are told to use public transport, take short showers and turn off the lights. Although these choices have some impact on the environment, there is a more significant aspect that only a few of us ever consider: our diet. With time, I have realized that I cannot call myself an environmentalist and still continue to consume meat and animal products. I became a vegan a year ago — and since then have already saved around 1,519,823 liters of water, 1,022 square meters of forest, 365 animal lives, 6,607 kilograms of grains and 3,322 kilograms of carbon-dioxide. Although meat and other animal products are an integral part of Austrian culture, had I known about the difference I could make by changing my diet, I would have done so long before.

Animal husbandry is a key cause of climate change, as a meat-based diet requires more energy, land and water resources. Meat and dairy products only make up 18 percent of all calories consumed worldwide and 37 percent of all protein available for consumption, but utilize 83 percent of the world’s farmland. As the world’s population rapidly increases, this becomes inefficient and unsustainable. A major issue is that the farmland being used for grazing has been specifically deforested for that purpose. For example, in Brazil — the largest exporter of beef in the world — 91 percent of the cleared area of the Amazon rainforest has been converted to accommodate [cattle ranching] (http://documents.worldbank.org/curated/en/758171468768828889/pdf/277150PAPER0wbwp0no1022.pdf).

Not only is this unsustainable for the rainforest, but is also unsustainable in terms of water use. Consuming just one kilogram of beef requires 15,415 liters of water, while one kilogram of vegetables requires only 322 liters. 97.5 percent of the world’s water is salt water, which is not usable for agriculture, leaving only 2.5 percent freshwater, of which over 70 percent is consumed by the agricultural sector. The majority of this water goes to animals; on a per kilo basis, the production of beef, pork and chicken require around nine, four and three times as much water as cereals respectively. This is because animals consume water directly and indirectly through their feed. A quarter of all crops grown is fed to animals, representing half of all protein and over one-third of all calories produced. It also represents a staggeringly inefficient use of resources: meat and dairy products contain only 2.6 percent of the feed and pasture biomass fed to animals; the remaining 97.4 percent is lost. This practice is evidently unsustainable, as a large amount of resources are wasted to produce a small amount of protein. One could ingest exponentially fewer resources by practicing veganism.

Another factor that makes meat and meat-derived products unsustainable is their emission of greenhouse gases. The animal-product industry creates over 14.5 percent of the global greenhouse gas emissions, which is more than the emissions produced from powering all the world’s road vehicles, trains, ships and airplanes combined. Livestock production is also the largest source of methane and nitrous oxide, which are particularly harmful to the atmosphere. Again, it is beef and dairy that contribute the most when it comes to GHG, with beef and dairy emitting around 150 times and pork and chicken 20 to 25 times more GHGs than soy products. Because of the deforestation connected to the clearing for cattle ranching, nearly a billion tons of carbon is released into the atmosphere per year, both directly, as forests are cut down to provide pasture or are degraded through animal grazing, and indirectly, as rising demand for animal feed drives the expansion of cropland into forests.

It is a lack of knowledge about how diet and climate change are related that makes consumers less willing to change their habits to reduce emissions. I did not know anything about food and climate until I informed myself and chose to accept the information. It is possible to make a gradual change in diet by starting to replace first meat, then milk products, eggs and finally, fish, with soy-based and other alternatives to help reverse climate change. This approach has far more rapid effects on GHG emissions than replacing fossil fuels with renewable energy.

It is our responsibility as humans to do something to save our planet, but it is your choice if you are willing to actually commit. A gradual change in diet is all it takes to immediately lessen your negative impact on our environment. I did it, and so can you.