I think I have flat feet. Someone told me I stand like this (see photo). Is this a symptom of anything, or something to be concerned about?
The rolling in of the ankle when standing is called pronation, and is not believed to be a symptom of any illness or
Pronation is a natural part of our body's motion in the lower leg and ankles while walking.
Excessive or overpronation could potentially contribute to misalignment of joints and subsequently stress other joints or connective tissue (knees, hips, shins, back, etc.).
There are two schools of thought:
In studying biomechanics and working at a running store, I would watch peoples' gait when they walk/run and fit properly for shoes that match the level of overpronation, if it is an issue. There are certain categories of athletic shoes that provide various levels of pronation control.
A specialty running-walking store may be knowledgeable enough to watch your gait and fit you properly if you're concerned or experiencing discomfort because of overpronation. This is the traditional way of thinking about overpronation, by essentially controlling it.
To learn more about this, search and read up on shoe fitting, gait analysis, and pronation. If it's any help, customers who were overpronators and/or had collapsed or low arches would come in daily; personally, I have not observed any correlation to immune or health issues (besides biomechanical as I mentioned above).
Since biomechanics is a continuously growing area of study, some physicians and researchers now maintain that strengthening the feet/lower legs could help resolve low arches or excessive pronation. This can be accomplished by minimalist footwear.
Minimalist footwear means that there is no forced control of that "rolling in," or pronation, but instead, slowly trains the muscles in the feet to eventually adapt and self-correct. It's like strength training for your feet! Transitioning to minimalist footwear must be done very slowly to avoid injury. Though patience is necessary over the 6 months - 1 year to fully transition, it could result in many lasting benefits by improving joint alignment, and reducing discomfort or pain in the shins, knees, hips, or back.