Does heating destroys turmeric benefits?

Yes and No.

Turmeric has been used as a spice in India for thousands of years. Most Indian curries require heating the spice along with other ingredients. But research says prolonged heating > 30 min destroys substantial % of curcumin.

Heating for a short span of time would not have that effect. Thus, its best to add turmeric in the end if possible in your recipes.