Kat Kerlin, UC DAVIS NEWS
Eating Too Much Protein Adds to Nitrogen Pollution in U.S. Waters
…when a body takes in more protein than it needs, excess amino acids break it down into nitrogen, which is excreted mostly through urine and released through the wastewater system. This brings additional nitrogen into waterways, which can result in toxic algal blooms, oxygen-starved “dead zones” and polluted drinking water.
Balancing how much protein you eat with the amount your body needs could reduce nitrogen releases to aquatic systems in the U.S. by 12% and overall nitrogen losses to air and water by 4%, according to a study from the University of California, Davis.
Protein consumption in the United States, from both plant and animal sources, ranks among the highest in the world. The study, published in the journal Frontiers in Ecology and the Environment, said that if Americans ate protein at recommended amounts, projected nitrogen excretion rates in 2055 would be 27% less than they are today despite population growth.
The study is the first to estimate how much protein consumption contributes to excess nitrogen in the environment through human waste. It also indicates that coastal cities have the largest potential to reduce nitrogen excretions headed for their watersheds.
“It turns out that many of us don’t need as much protein as we eat, and that has repercussions for our health and aquatic ecosystems,” said lead author Maya Almaraz, a research affiliate with the UC Davis Institute of the Environment. “If we could reduce that to an amount appropriate to our health, we could better protect our environmental resources.”