You probably prepare a tomato sauce from time to time at home, but do you practice putting the garlic in the hot oil right after you chop it? If you do this, you are making a huge mistake.
Putting the chopped garlic in hot oil right away makes all the allicin from it to disappear, and it is the compound of garlic that makes it so healthy.
The enzyme needed for production of allicin is activated only after you peel garlic, and the immediate contact with high temperature destroys it right away.
If you want to input allicin you will have to leave the chopped garlic on the board at least for ten minutes. It would be even better if you mash the garlic instead of chopping it.