I also take issue with the preload carb comment.  
If you want your body to start using fat for energy, you need to coerce your body to do it.  
Very low carb (ketosis) for couple weeks on a deficit will do it.  Then gently work minimal complex carbs back into your diet.  
Mark Sisson’s Primal blueprint book covers this topic well and works really well for most people in my experience. Hes done a bunch of podcasts if you want to learn a bit about him before diving into a book.
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