I recently had someone ask me if their backpain was related to the fact that they wore high heels the day before. My answer? Maybe...hard to say. It is not a secret that high heels can put added stress to the low back, ankles and feet. The lifting of our heel changes our centre of gravity and our body shifts to accomodate. We can not avoid stress entirely, nor do we necessarily want to, the bigger question is our body adapting appropriately to the stress.
It may be worth clarifying that there are multiple categories of stress where these ideas can be applied. High heels refer to more of a physical stress, however chemical stress (i.e. alcohol, sugar, etc.) and mental/ emotional stress (i.e. new job, lay-off, wedding, divorce) also apply. A healthy body is able to adapt to, what should be, a temporary stress.
Problems surface when the stress is no longer temporary. If a woman only ever wore high heels, eventually the body would adapt differently and problems may surface. Shortened achilles (the tendon at the back of the ankle), extra pressure on the lower spine leading to back pain, or even changes to the forefoot to accomodate the regular weight load distributed. In moderation however, the body has a chance to "bounce back" more easily so permanent changes don't take place. Even with moderation, ensuring a counter-action to help mitigate the stress produced on the body can provide further benefit, such as stretching the ankle/ calf after wearing heels.
In the response to the initial question, I equated high heels with chocolate and red wine (hard to tell what my vices are haha). Once in awhile, a glass of red, a little chocolate, is not a big deal and should not derail your health. If they became two main food groups however, you most definitely would note some negative repercussions.
When healthy, the 80/20 rule is a fair approach. If 80% of the time the best choices are made...eating the quality and quantity of food that is appropriate and necessary, participating in a well-rounded activity schedule (and as it relates to the above scenario, avoiding undue stress to our physical body), and maintaining an appropriate level of mental stress, then if in the other 20% of the time we choose to indulge, we really should be able to adapt and continue moving forward in a healthy way.
Be honest with the choices you are making 80% of the time. Journal if necessary to stay accountable and see where you may struggle the most, and acknowledge yourself for where you are living a life that will lead you to the outcomes you desire. Being healthy is about choice, not restriction or deprivation.