Aim: To investigate morphofunctional changes in the endocardium, arteries’wall of different types, prostate and adrenal glands, taking into account age-related characteristics on the 60th and 90th days of iodine deficiency combined with goitrogen consumption. > Materials and Methods:The experiment was conducted on 50 white outbred male rats (25 sexually immature, 3–5 months old, and 25 sexually mature, 6–8 months old). Eleven animals from both age groups formed the control group, and 14 animals from the second and third experimental groups were subjected to simulated iodine deficiency combined with goitrogen consumption. Material collection was carried out on the 60th and 90th days of the experiment. Morphological (light andelectron microscopy), morphometric, biochemical studies, and statistical data analysis were performed. > Results:On the 60th day of the experiment, the cholesterol content was: in sexually immature rats, 1.66 ± 0.19 mmol/L (p < 0.01); in sexually mature ratswas1.44 ± 0.15 mmol/L (p < 0.01). Ioduria in sexually immature animals of Group 2 was 1.42 ± 0.16 μg/L, and in sexually mature animalsit was1.92 ± 0.21 μg/L (p < 0.01).On the 90th day of the experiment, edema changes in the endocardium progressed. In lightmicroscopystudies, the endocardium appeared as a veil-like strip covering the myocardium. In the light pink cytoplasm, flattened and weakly basophilic endothelial nuclei were visible. The content of endothelin-1 in the blood of sexually immature animals increased by 5.7% (p < 0.05), while in sexually mature animals, it rose by 2.4% (p < 0.05). > Conclusions:Thelevel and degreeof iodine deficiency is confirmed by ioduria indicators and thyroid profile. In all studied organs, edema changes develop in all constituent structures already on the 60th day of simulated iodine deficiency, progressing to the 90th day of the experiment.