Objective: The aim of this study was to evaluate the effects of passive smoking on diet quality, oxidative stress index and nutritional status.

Materials and Methods: It was a cross-sectional case-control study. The study was conducted in Bingöl with 40 participants aged 19-35. Participants were divided into two groups: passive smokers and non-smokers who were not exposed to smoking. Seven days of 24-hours food consumption status’s data were collected and diet diversity score (DDS), healthy eating index (HEI-2005) and diet quality index (DQI) were calculated. In addition, participants' physical activity levels were determined by the international physical activity questionnaire (IPAQ). Statistical data were evaluated by SPSS 22.0 statistical package programme.

Results: The average age of participants were 21.7 ± 1.5 for men and 20.3 ± 0.8 for women. According to the study groups, except the diet energy of protein ratio, PUFA (Polyunsaturated fatty acids), Vitamin A, Vitamin E and Vitamin B12 other nutrients were significantly different in the control group compared to passive cigarette group (P<0.05). There was no significant difference between groups’ serum TAC (total antioxidant quality) levels (P>0.05), but TOS (total oxidant status) and OSI (oxidative stress index) were high in passive group (P<0.05).

Conclusion: The negative effects of smoking on health are well known. In terms of prevention of illnesses and improvement of health, awareness of individuals about smoking, support of nutrition and physical activity, regulation of nutrition habits will be effective in protecting health against diseases that may arise during old age, especially preventable diseases.