Comparative analysis of cognitive functions and learning success in military cadets with vitamin D level in body: experimental sutyd

OBJECTIVE. Determine vitamin D status and its effect on cognitive functions and learning success in the fourth-year cadets.

MATERIALS AND METHODS. A pilot survey of 108 cadets (average age – 20 ± 1,4 years), studying in a military higher education institute of St. Petersburg, was conducted. Vitamin D body supply, the level of cognitive function development and success of learning activities were investigated. Vitamin D content was determined on a “Mindray” apparatus by enzyme immunoassay method. To assess the level of the development of cognitive functions, we have used tests aimed at diagnosing spatial figurative and verbal-logical thinking, memory and attention. The average grade for the year was considered as a criterion of success in learning activities.

RESULTS. When evaluating the level of vitamin D content, 31 (28,7 %) cadets experienced severe deficiency, 40 (37 %) – moderate deficiency, 21 (19,4 %) – mild deficiency and 16 (14,8 %) had its optimal level. No differences were found in the results of performing tests aimed at diagnosing thinking, memory and attention in cadets with deficient and optimal levels of vitamin D (p > 0,05). There has been direct correlation between learning success and vitamin D content in the body (p < 0,01).

DISCUSSION. The hypothesis about the effect of vitamin D concentration on level characteristics of thinking, memory and attention at a young age has not been confirmed. The results obtained are echoed in other studies aimed at investigating the effect of vitamin D supplementation on cognitive function in young healthy adults.

CONCLUSION. The study results have shown that low vitamin D status in young adults does not significantly affect the level characteristics of thinking, memory and attention. Vitamin D deficiency in young adults (on the example of military cadets) is a predictor of lower efficiency of cognitive functioning in the process of learning activity performance.

marine medicine, vitamin D, cognitive functions, memory, attention, thinking

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