Circadian rhythm of plasma levels of lipids, carbohydrates and various hormones in healthy pilots

Circadian variations of plasma lipids (cholesterol, total lipids, triglycerides, beta-lipoproteins), sugars and selected hormones (cortisol, testosterone, estradiol, aldosterone) were measured in 30 healthy pilots, aged 30-39 years. The control group consisted of 15 healthy nonpilots of similar age. Experimental data were statistically treated using cosinor analysis. In contrast to the ground-based personnel, the pilots showed in increase in the average daily content of lipids and hormones, a decrease in the average daily content of sugar, and an increase in the amplitude of cholesterol, triglycerides, total lipids, beta-lipoproteins, cortisol, testosterone and aldosterone. Estradiol rhythms were very similar in both groups. Acrophases of triglycerides, testosterone and estradiol were almost synchronized. Acrophases of other parameters were different in values which were greater than the acrophase drift range. The specific features of circadian rhythms of plasma lipids, carbohydrates and hormones seem to reflect the specific features of professional activities of pilots. The above investigations of circadian variations of plasma lipids, carbohydrates and hormones in healthy pilots represent the first attempt of recording circadian parameters of their biochemical substrates.