In my opinion, the problem begins with misunderstandings about how feet function. Feet are indeed extremely important to humans for survival. There’s a reason we invented shoes in the first place! However, like many things that are extremely important to us, modern humans have gone overboard. At one point sugar, salt, and rest was crucial for our survival. Now we’ve got excess sugar and salt in foods and much of our day is spent being sedentary. Resulting in modern disease or as evolutionary biologist Dr. Lieberman calls them ‘mismatch diseases’ of diabetes, hypertension and a number of diseases associated with a lack of movement including obesity. 

Our modern foot has experienced something similar. We’ve ‘babied’ our precious feet with cushioned and restrictive shoes. We walk on simple flat surfaces that don’t challenge our feet (and body). As a result the 33 joints in feet (66 in total) don’t experience the movement they were designed to experience. It doesn’t take an anatomist to understand that joints are meant to move!

When joints don’t move they start to weaken and/or overuse tissues. Modern humans’ solutions to pain is often to ‘off-load’, cast, and restrict movement. This solution works for serious acute injuries such as fractures and tears in the short term. Unfortunately it does not work for many others. You would never cast an arm if you had tennis elbow (lateral epicondylitis) so why would it make sense to essentially cast your foot with an orthotic for plantar fasciitis?

I could see the benefit to using orthotics as a temporary tool to potentially ‘off-load’ an aggravated area. Unfortunately this does not always happen. I have had many clients report that their orthotics are not comfortable and making their symptoms worse. Yet many of them continue to wear them because they have been convinced that they are supposed to work!

And when the orthotics are comfortable, they can be even more dangerous. If someone starts to rely on the external support from an orthotic your foot joints and muscles are no longer needed and therefore atrophy. This can bring on issues to your feet themselves but more often leads to issues elsewhere in the body that are compensating for the weak feet. 

Unfortunately even the research on orthotics doesn’t look good. There is no quality evidence to support that orthotics reduce your risk of injury. A 2018 randomized control trial determined that there was NOT sufficient high quality evidence to support the use of orthotics (Healy et al., 2018). A 2019 paper by Tran and Spry, determined that there was NO difference between custom orthotics compared to simple Over-The-Counter (Prefabricated) orthotics. This is alarming for an expensive product that is so commonly used and prescribed by so-called medical professionals!

The research that is often cited by orthotics companies shows no significant difference over the placebo group. When an orthotic costs upwards of $500 there surely is a placebo effect at play. Unfortunately this costly orthotic is no more effective than the $50 one you can get at the drugstore.