Diabetes mellitus is one of the worldwide largest growing metabolic diseases. In this study the effects of consumption of raw garlic on serum lipid level, blood sugar and a number of effective hormones on lipid and sugar metabolism (thyroid hormones and insulin) in individuals either with high level of blood sugar or lipid were investigated. Eighty five volunteers having following clinical history enrolled in the study: Group 1: having blood sugar more than 126 mg/dl (30 volunteers); Group 2: having cholesterol higher than 245 mg/dl (30 volunteers); Group 3: having blood sugar over 126 mg/dl and cholesterol more than 245 mg/dl (25 volunteers). In group 1, there wasn't a significant differences between biochemical factors before and after garlic consumption, whereas, in the second group after 6 weeks of garlic consumption a decline in cholesterol (P < 0.001), FBS and TG (P < 0.01) was observed but HDL-C (P < 0.001) was increased. Six weeks after termination of garlic consumption, cholesterol (P < 0.001), FBS and TG (P < 0.05) were increased and HDL-C (P < 0.01) was decreased. In the third group, total cholesterol (P < 0.001), FBS (P < 0.01) and HbA1c decreased while HDL-C was increased. Other factors, including thyroid hormones (T3, T4), TSH and insulin showed no significant alteration. In conclusion our results shown that raw garlic consumption can reduce the FBS and Lipid in hyperglycemic and/or hyperlipidemic individuals.