“…Consequently, for clinical applications, targeting anatomical regions with substantial homogeneity is a prerequisite. Recently, using spatially resolved diffuse reflection spectroscopy, reference [31] demonstrated a relation between changes in the determined water index and the change in body weight due to heat, physical exercise and diuretic therapy. Although the errors bars in the measured water index were relatively large, they interestingly, found a 10-fold larger effect in the dehydration of the dermis compared to the body weight loss, which may loosen the needed σ μ OCT .…”