7. Endocrinology

Most of the diabetes-induced end-organ damages are impairments in the blood-vascular system caused by elevated blood sugar. Smoking harms the circulatory system through at least five different mechanisms: by developing constrictions (stenoses) and obstructions in blood vessels, coronary artery spasms, ventricular arrhythmias and lowered oxygen level in the blood.

Tobacco smoke contains several substances that affect the thyroid gland. Cyanide of the tobacco smoke is converted to thiocyanate in the human organs, which prevents the absorption of iodine and the normal hormone production of the thyroid gland.