Silicon is the second most prevalent element in the Earth's crust and the third most abundant trace element in the human body. Silicon compounds counteract the crystallization of minerals in the urinary tract, impede the deposition of lipid plaques in the walls of blood vessels and through their presence prevent the absorption of calcium compounds, which reduce the elasticity of blood vessels and may cause diseases of the circulatory system. The article presents the results of studies on the level of silicon and magnesium in the hair of patients with atherosclerosis (N=137, age 60-94) and the control group of healthy people (N=242, age 20-80). The measured silicon content by ICP-OES in healthy people decreases with age, especially after 40 years of age, and ranges from 43.3 ± 7.8 to 22.4 ± 8.4 μg g-1. The average level of silicon in patients with atherosclerosis is much lower and ranges from 14.0 ± 6.7 to 7.9 ±4.9 μg g-1, depending on the age range. However, a wide spread of Si values is observed in every age group, even in the group of healthy military students living for several years in the same conditions and using the same diet. Among the patients, there is a group with Si levels below 10 μg g-1, a value that does not appear in healthy people, even those aged 70-80. Due to the presence of a concentration range of 10-20 μg g-1 among all tested samples, the Si content in the hair cannot be unequivocally considered a certain atherosclerosis marker, although particularly low Si content below 10 μg g-1 should be a clear signal heralding a disease. In such patients, there is also a significantly reduced level of magnesium (5-15 μg g-1) compared with the norms adopted in Poland (25-35 μg g-1).

25.4.2020