Nitrate water filters are necessary because nitrate levels above 10 ppm can certainly be harmful to humans. In some areas water with high nitrate levels are restricted for pregnant women, as there is a risk of blue babies disease. The good news is that nitrates are easily removed and controlled, and are normally inexpensive to buy.
You can either add a nitrate filter to just your drinking water at a very nominal cost. Or you can add a whole house nitrate filter to remove nitrates in the entire building. And while that may sound like it would be very expensive, it really is not. You can read more about nitrate filters and their cost on this page: https://waterfiltersofamerica.com/nitrate-filters/