Question about age of calories

jicarter01

Ok so we all know the body stores calories as fat. My question is: Are the calories that were stored in my body as fat from 10 years ago that I have never burned (like the bottom levels of belly fat from a beer I drank in high school) still the same calorie??? Or does the body use the oldest calories first and replace like food in a storage cooler (FIFO)??? Just curious.