Heat, which is the most destructive to nutrients can be controlled very precisely. This will insure cooking at lower temperatures. Besides preserving the nutrients in the food, thermal cooking preserves the natural flavors in the food. When cooking homemade soup in the thermal cookware, you're not losing the aromatic flavor into the air. Everything is locked into the vacuum sealed thermal cookware.
Grains have many nutrients that are sensitive to heat and oxidation.
Thermal cooking insures that you preserve the nutrients by not overcooking the grains. The best part is you don't have to worry about the grains sticking to the bottom of your pan when it's time to clean up.