Spirulina, soy, chia or pumpkin seeds… Alternatives to meat are popular because they fill up on protein. If you have decided to choose them to reduce the carbon impact of your food on the planet, be aware that overfilling would not be wise either: it would contribute to nitrogen pollution. Explanations.
We find it in our sirloin, but also in our fried egg or even in a bowl of lentils or a bean sprout salad… Proteins are an essential component of our body because they constitute muscle tissue and participate in the renewal of cells in bones, hair or nails. Of animal or plant origin, this family of macronutrients must represent between 10 and 27% of the daily energy intake of an adult under the age of 60, indicates the National Food Safety Agency (ANSES). More concretely, 100 to 150 grams of meat, fish or egg more than cover these needs, according to the national health nutrition program “Eating and Moving”.
And that’s all ! When you consume too much protein, the excess is filtered by the kidneys and then eliminated in the urine. This is how urea is formed, a kind of waste that is distinguished by its nitrogen-rich compounds. Added to the nutritional problem is another concern of which we were not aware beforehand, that of environmental pollution with nitrogen. And that’s where the whole problem lies !
The scientific journal Scientific American reports that nitrogen can decompose and form oxidized nitrogen gases that can end up in the atmosphere. In this case, the process contributes to global warming by supporting the presence of greenhouse gases. In the end, our excessive protein consumption, which ends up in the urine, ends up being detected in the waste water, and therefore potentially also that of the tap. This is how scientists have proof of the impact of the proteins in our diet on the environment. The observation is clear: 67 to 100% of the nitrogen pollution found in wastewater is produced by what humans eat.
So there is good news: we have the means to act to reduce the supply of nitrogen that pollutes the soil and the atmosphere. Because according to an American study by the University of California at Davis, published in the journal Frontiers in Ecology and the Environment, if the American population consumed the right amount of protein corresponding to the recommended doses, the nitrogen rejection rates in 2055 could be 27% lower than today, even if the number of inhabitants in the country of l Sam rises. Americans are the benchmark for this study simply because the United States is one of the biggest protein eaters.
The technology, too, could help remove nitrogen from wastewater, by up to 90%. Already developed, it is unfortunately expensive to set up. Only 1% of wastewater in North America benefits from it…
(ETX Daily Up)