No need.
All of those food you mention have more available nutrition when cooked then raw. When they are raw many of the nutrients are locked up inside the fiber and pass through the body without being absorbed.
When the fibers have been softened by cooking the nutrients trapped are available for the body to absorb.
So while the heat of cooking destroys some of the nutrients it frees up more.
The most dramatic example would be a mostly stripped joint.
You could gain a little nutrition by gnawing on it, more by splitting the bone open and scooping out the marrow, still more by roasting the bone and then scooping out the marrow but you would gain the most nutrition by roasting the joint, splitting it then putting it in water and boiling it for about three days.
This would give you a nutrient rich bone broth.
Depends on what you are eating...
http://www.scientificamerican.com/article/raw-veggies-are-healthier/