Detox foot patches and Bad Science

I was happily reading Bad Science: Quaks, Hacks and Big Pharma Flacks by Ben Goldacre and applauding the clarity of his essays against 'pseudo-science'  when I came across a section on detox foot patches. 

I no longer have the book in my possesion and cannot quote sections, but Mr Goldacre basically debunked detox foot patches. This came a bit of a shock as I am a big fan of detox foot patches. I even used them throughout my pregnancy to relieve my body aches!

One of the points Mr Goldacre made was that the foot patches consists of ingredients which would turn dark upon absorbing moisture, much like silica gel changes colour in a humid environment. The 'supposedly detoxed/darkened patches' were nothing more than a colour change due to absorption of moisture.

I decided to test this out (to the best of my abilities). 

I opened 4 patches and did the following:

A) Applied 2 patches to the balls of the feet. Feet were dry before applying.

B) Applied 1 patch to the ankle of one leg. The right leg had 1 patch on the inner ankle and 1 patch on the ball of the feet. 

C) Left 1 patch on the tabletop exposed to the same air-conditioned environment as my sleeping conditions. I even 'covered' half of the patch with a towel to simulate the blanket. I was unable to turn and toss this exposed patch similar to my movements while asleep.

Original detox foot patch when removed from its plastic packaging 

Applying 2 patches to the balls of my feet 

Applying 1 patch to the ankle 

1 patch left out on the table and 'covered' with a 'blanket' - to simulate what happens when I fall asleep

I promptly went to bed and removed the patches when I woke up in the morning. The patches on my feet showed their usual, darkened, slightly moist goopey side. The patch placed at the ankle showed a small corner of darkened & moist surface. The patch left out in the open showed no changes.  

1 & 2 - patches on the balls of my feet

3 - patch placed at ankle 

4 - patch placed at tabletop 

I believe, detox foot patches work on the theory that since every point on the sole corresponds to a part of the body, drawing the toxins out via the sole will similarly draw out toxins from the corresponding part of the body.

Close-up of patch placed at ankle and patch left out in the open

I admit, I had never given the science of detox foot patches much thought before reading Bad Science. Even after reading the book, I'll freely admit that I don't understand how these patches work or why they should make me feel better. It could be a placebo effect or just the impact of a good night's rest on the body.

If Mr Goldacre is entirely correct, then the patch placed at the ankle should show more change as the patches on the feet (since both the sole and the skin on my ankle would perspire during my sleep). The patch left out in the open did not change due to 1)the air conditioned environment is dry and there is no moisture to turn the patch darker or 2)the patch did not come into contact with skin/toxin so there is no change. 

I will continue to use up my current supply of detox foot patches but I might not continue to purchase any in the future until I've figured out the science/philosophy behind this. As it is, I do feel better after using the detox foot patches but I have no way of knowing for sure how much of it is due to the detox foot patches.