In (a) 3T3-L1 cells cultured in differentiation media (high glucose, 25 mM) until day 6 and in growth media (low glucose, 5 mM) afterwards. (b,c) 3T3-L1 cells cultured in differentiation media until day 6, on which cells are incubated for 48h (d8) using three different culturing conditions: in growth media (Low gluc, 5 mM), in differentiation media (High gluc, 25 mM) and in differentiation media with 5 nM of GLUT1 inhibitor (GLUT1 Inh). In both, a and b, the mean CBR/c for micrographs of differentiating 3T3-L1 cells measured at 1022 cm-1 fairly correlates with the read-outs obtained by the total carbohydrate assay applied to the imaged dishes (see Methods). Carbohydrate contrast obtained by MiROM accurately reflects the glucose stimulation of the imaged cells accordingly. In a, for both methods each measurement point is the average of two cell-dishes; including the measurement series shown in main Fig. 2f–n. Only the measurement points at day 10 in a slightly shifted from the same trend, most probably reflecting the presence of additional molecules detectable by MiROM for which the assay is not sensitive, e.g. glycerol with an absorption band around 1022 cm-1. Data in a,c are presented as dot plots (n=2 per time point; error bars represent mean ± s.d.).