Related to cycloalkanes, the application of HPT processing in human milk samples caused relevant reductions in the levels of these compounds with respect to those found in untreated samples. Some of these reductions were highly noticeable (p < 0.05) after the application of HPT processing at 80 °C, particularly in 1,2,4-trimethyl-(1α, 2α, 4β)-cyclopentane and methyl-cyclooctane.