Serum beta-carotene, lycopene and alpha-tocopherol levels of healthy people in northeast Thailand

Human serum contains many different antioxidants which may be important in the maintenance of antioxidant status. beta-carotene and lycopene are carotenoids with potent antioxidant activity. Carotenoids intake probably protects against cancers and may affect the risk of several chronic conditions. alpha-tocopherol is well known for its function as antioxidant and in reduction of heart disease and cancer risk. We aimed to establish baseline values for serum beta-carotene, lycopene and alpha-tocopherol concentrations in healthy northeast Thais. Fasting serum beta-carotene, lycopene and alpha-tocopherol levels from 294 subjects aged 23-75 years old in northeast Thailand were determined by high performance liquid chromatography (HPLC). The mean serum beta-carotene, lycopene and alpha-tocopherol levels were 0.53 +/- 0.32 micromol/L, 0.57 +/- 0.37 micromol/L, and 26.64 +/- 14.85 micromol/L respectively. Serum beta-carotene and lycopene levels in females (N = 118) were significantly higher than the value for males (N = 176), ie 0.60 +/- 0.31 micromol/L versus 0.48 +/- 0.32 micromol/L (p = 0.002) for beta-carotene and 0.74 +/- 0.38 micromol/L versus 0.46 +/- 0.33 micromol/L (p<0.001) for lycopene whereas alpha-tocopherol level in males (28.60 +/- 14.34 micromol/L) was significantly higher than in females (23.72 +/- 15.16 micromol/L) (p = 0.006). beta-carotene level was positively correlated with alpha-tocopherol (r = 0.22, p<0.001) and lycopene levels (r = 0.63, p<0.001). The results from this study give the baseline data of serum beta-carotene, lycopene and alpha-tocopherol levels in healthy northeast Thai population and also suggest future study on the relationship of dietary intake.