I HAVE BEEN HAVING EPISODES WHERE MY LEGS GET COLD

I HAVE BEEN HAVING EPISODES WHERE MY LEGS GET COLD FROM THE INSIDE OUT AND NUMB AND I FEEL LIKE I AM GOING TO PASS OUT. IF I EAT PEANUT BUTTER CRACKERS OR SOMETHING IT HELPS BUT IT DRAINS ME FOR A FEW DAYS. WHAT COULD THIS BE? IT IS HAPPENING MORE FREQUENTLY.