Over time, your feet may appear flatter due to the natural progression and biomechanics of your foot.  When your foot hits the ground heel first, the foot elongates and flattens, which allows the foot to roll inward in normal gait.  Some factors such as weight gain will put extra pressure on the longitudinal arch of the foot, which runs on the inside of the foot from the inner heel to the balls of the foot, causing the arch to flatten.   Age, hormonal changes, or injury can also affect the tendons and ligaments of the feet.  This is especially true for the posterior tibial tendon, which aids in holding up the arch of the foot. Over time, this tendon stretches out and is unable to perform it's function as efficiently, again causing flattening of the feet. This may also be the reason why your feet appear to "grow" in size and you may need to increase your shoe size by one half or full size. Whatever your ailment, and we can evaluate and assess your foot problems and come up with a solution.