Our food contains a lot of (micro) nutrients, but our body only uses 1% of these nutrients. The other 99% we poop and pee out again. This is equal to the amount of nutrients our land needs for the next harvest. Unfortunately, we do not return these (micro) nutrients to the soil. To keep the crops growing we then import fertilizer, but fertilizer has some major flaws. The production uses fossil fuels and emits a lot of CO2. The nutrients used are mined from limited sources and fertilizer contains few essential micronutrients that leave us with an impoverishment of the soil. These micronutrients, on the other hand, are abundant in our poop and pee streams and could be from great use to create a healthy soil. But what do we do with them? We go to a tiny locked room and flush them away. Because these flows are diluted with other water flows (showering, cooking and sometimes rainwater), a lot of time and energy is needed to return to clean drinking water and various residual flows (such as sludge). The products obtained from these residual flows are generally not good enough to provide the soil with the necessary (micro) nutrients. These micronutrients have been lost in the process.