Significant seasonal variations have been found by several authors in serum lipids. The aim of this study was to determine whethere there were seasonal variations in serum lipid concentrations in Korean healthy population.

The subjects consisted of 20,819 men and 10,248 women screened between January in 1997 and December in 1997. We performed spectral analyses to confirm whether there is seasonal variation in serum lipid levels.

The monthly serum total cholesterol, HDL cholesterol and LDL cholesterol levels were significantly higher in the period from September to December with the peak in October (p<0.001, except, HDL cholesterol p<0.02), and by the seasonal analysis, these lipid levels in autumn were significantly higher than those in spring and summer (p<0.001). Those patterns of monthly and seasonal variations were similar in both men and women. Howevere triglycerides levels were slightly different by the sex. In men, significantly increased triglycerides levels were found in the period from August to December with the peak in September and those in autumn were the highest (p<0.025). In women, serum triglycerides levels were significantly higher in the period from July to February with the peak in December (p<0.04). Serum triglyceride levels in winter were higher compared with in spring and summer (p<0.001). Additionally, we analysed the seasonal variations of serum lipid levels according to the body mass index (BMI) and the age groups. In these analysis, there were also similar patterns of seasonal variations in serum lipid levels (p<0.001).

Above results show that there were prominent seasonal variations of serum lipid levels with higher in autumn and winter compared with those in spring and summer.