It is scientifically proved that being happy makes you younger, think about your body as a machine that works with vibrations that activate each one of your DNA particles to renew itself every day, those vibrations are produced by your feelings which are created by your thoughts and memories, so when you have good memories and positives thoughts you are sending positive vibrations to each one of the cells in your body and therefore they do this renovation process faster, when your thoughts and feelings are negative your body react to that by not working properly causing diseases and pain.
I have noticed that the more I think about things that make me happy and make me smile the better my body feels and the more amazing my memories are of each moment, the other great perk about it is that other people notice this kind of good vibrations that your body produce and they are positively affected by the power of your thoughts so amazing things start to happen to you just because you are genuinely happy and other people want to be happy around you too, I invite you to practice this simple exercise each time you remember something try to pick a positive thought and you will see the ripple effect it will have in your life just by doing this your whole mood and vibrations of your body become positive energy and attract more positive energy that combined can change anything and everything you want at your will.