Nutritional Status And Effect Of Supplementing Vitamin E, C And Beta-carotene On The Antioxidant Activities In The Old People

Objective: To investigate the nutritional status by a dietary survey, and the antioxidant activities by supplementing vitamin E, C and beta-carotene in the old peolpe.Methods: 1. Carried out prospective trial after getting ethic permission and obtaining agreements and signatures of each subject. Divided the subjects into different groups at random and offered them with VitE, VitC and β -carotene for 16 weeks.2. 240 subjects, which were 109 males and 131 females in age of 60-75 years, were selected to participate in the trial, the average age was 66.87 + 5.49 years. Then they were randomly divided into 4 groups, which were supplemented in group I with 300mg VitC + 200mg VitE + 16.70mg β -C, group Ⅱ with 300mg VitC + 200mg VitE + 8.35mg β -C, group Ⅲ with 300mg VitC + 200mg VitE + 5.57mg β-candgroup Ⅳ with 300mg VitC + 200mg VitE.3. A 24hr diet recall for the old people was usded to investigate their total quantity of diet, assess their food consumption, nutrients intake and the constitution of diet. Samples of fasting blood were collected twice before and at the end of the intervention trial to examine the activities of antioxidant enzymes including superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in the plasma as well as the hemolytic degree of red blood cells (RBC) in the old people.Results: 1. According to the investigation, the average daily intake of grain, vegetable, fruit, legume, poultry, milk, egg and aquatic food of the investigated subjects was 292.17,152.98,15.29, 31.45, 47.90, 18.48, 61.45 and 53.34 grams respectively. The average daily intake of energy of the investigated males and females was 91.79% and 85.20% of RNIs; protein was 91.44% and 87.11% of RNIs, VitE was 60.71% and 53.93% of AIs, retinol was 64.04% and 58.31% of RNIs, and VitC was 63.90% and 56.24% of RNIs respectively. In the source of energy, 70.20% was from vegetation, 22.76% from animal food and the rest from pure energy food; in the source of protein, 39.66% was from grain, 11.59% from legume and 38.68% from animal food; moreover, in the males and females of the subjects, 66.20% and 69.70% of the total energy was provided by carbohydrate, 17.49% and 15.81% was provided by fat, and protein provided 16.31% and 15.12%, respectively,2. Nineteen persons withdrew during the period of the trial, the missing ratio of the subjects was 7.92%(19/240). There were no differences in hemolytic degree of RBC induced by H2O2, and the activities of SOD and GSH-Px in plasma between groups before intervention. After 16-week intervention, the hemolytic degree induced by H2O2 in each group was decreased by 28.83%,...