Background. It is well known that inadequate nutrition could be the cause and a risk factor for many noncommunicable diseases, including dysfunction of the digestive system, dental caries, osteoporosis and cardiovascular diseases. Dietary mineral composition is also very important for various physiological processes in the human body. Mineral water is anessential supplement for the renewal of plasma electrolytes. We have investigated the variation in blood serum electrolytes after the consumption of mineral water bottled in Lithuania.
Material and Methods. Blood samples of 30 individuals (19-20 years old) were investigated. Concentrations of sodium (Na+), potassium (K+), chloride (Cl-), calcium (total and ionized) and magnesium (Mg2+) in blood serum were evaluated. The aforementioned blood serum electrolytes were tested in blood serum samples of individuals four times overall: before the investigation, after 20 days of consuming mineral water (1 litre per day), after a 2-week break during which no mineral water was consumed, and after 20 days of consuming spring water (1 litre per day - placebo). Concentrations of Na+, K+, Cl-, Ca2+ (ionized) were measured with an ABL-620 analyzer, and total calcium and Mg2+ were measured with a Dimension RxL. These investigations were performed at the Centre of Laboratory Diagnostics of Vilnius University Hospital “Santariškių Clinics”.
Results. The concentration of ionized calcium in the blood serum of individuals consuming mineral water for 20 days increased significantly from 1.16±0.04 to 1.22±0.05 mmol/L (p<0.0001) and did not change within 2 weeks (1.21±0.05 mmol/L, p<0.001). The consumption of spring water significantly decreased the concentration of calcium (ionized and total) from 1.21±0.05 to 1.15±0.05 mmol/L, p<0.00005 and from 2.32±0.12 to 2.26±0.08 mmol/L, p<0.027 respectively. The concentration of Mg2+ in blood serum was increased only after a longer period. Concentrations of Mg2+ in blood serum amounted to 0.74±0.05 and 0.79±0.05 mmol/L respectively, p<0.003. While consuming mineral water, the concentration of Na+ did not change, but the concentration of Cl- - slightly decreased (from 103.57±1.72 to 102.23±1.7 mmol/L, p<0.007). One-third of the individuals investigated (32.1%) indicated increased frequency of defecation.
Conclusions. The consumption of mineral water for 20 days increased blood serum concentrations of Ca2+ and Mg2+ and slightly decreased the concentration of Cl- but did not influence the concentration of Na++ and K+.
