DIET AND LEVELS OF TWO ENDOGENOUS ANTIOXIDANTS, SUPEROXIDE DISMUTASE AND CATALASE, IN THE BLOOD OF SEVENTH-DAY ADVENTIST VEGETARIANS AND NONVEGETARIANS IN MAYERA AND DANSOMAN IN THE GREATER A

ABSTRACT Background: Vegetarianism is a dietary lifestyle that involves the restriction of diet, disallowing some or all foods of animal origin, thereby consuming mainly foods of plant origin. Vegetarian diets are composed of only plant products which include fruits and vegetables, as well as grains, legumes, nuts and seeds. The plant products they consume are rich sources of vitamins such as Vitamins A, C and E which act directly as antioxidants, as well as protein and minerals such as zinc, iron, magnesium and selenium, which function as co-factors for antioxidant enzymes, synthesized in the body. Free radicals cause cell damage and have been found to be an important contributory factor in the occurrence of diseases such as brain dysfunction, cancer, cardiovascular diseases. Little data exists on dietary composition and serum levels of endogenous antioxidants of vegetarians in Ghana. Objectives: The aim of the study was to compare the diet and serum and plasma levels of two common intracellular antioxidants in Seventh - day Adventist vegetarians and nonvegetarians in Mayera and Dansoman, in the Greater Accra region of Ghana. Methodology: A case – control study was carried out involving 39 vegetarians and 30 non-vegetarians. Blood pressure and anthropometric measurement (weight, height, visceral fat and body fat) was measured for all the participants. A structured questionnaire was used to obtain socio- demographic data of the participants. Dietary intake was assessed using a 24-hour recall and food frequency questionnaire. Venous blood samples were collected to assess serum and plasma levels of the endogenous antioxidants, catalase and superoxide dismutase. Results: The mean age of vegetarians and non-vegetarians was 36.1± 8.2 and 30.7± 7.6 years, respectively. The mean age between both groups was significantly different (p=0.007). Systolic blood pressure was significantly higher in vegetarians compared to non-vegetarians (p =0.049). There was a significant difference in the mean serum level of superoxide dismutase between vegetarians and non-vegetarians (p=0.044). However, there was no significant difference in the mean plasma level of catalase between both groups (p=0.075). Mean intake of protein was significantly different between both groups (p=0.001), whilst significant difference was found in the intake of the antioxidant micronutrient Vitamin E (p=0.006). Mean dietary zinc intake was significantly lower in the vegetarian group (p=0.000), compared to the non-vegetarian group. Dietary vitamin C intake in vegetarians showed a significant moderate positive correlation with SOD levels (p=0.04). Conclusion: Significantly high intake of dietary vitamin E in vegetarians could account for the significantly higher mean level of superoxide dismutase in this group. Comparatively higher intakes of Vitamins A and C in vegetarians, though not significant, could account for the higher levels of endogenous antioxidants in blood. There is therefore the need to examine more enzymatic antioxidants as well as to quantify dietary antioxidants.