Associations between dietary intake of flavonoids and antioxidant status and some inflammatory markers in women with chronic asthma

This study was designed and conducted to determine the difference between the intake of dietary antioxidant components (vitamins A, C, and E, and the minerals zinc, magnesium, selenium, copper, and flavonoids) between women with chronic asthma and healthy women, to examine the relationship between serum oxidative stress and some serum inflammation parameters and to evaluate the relationship with asthma risk. The study was carried out on a total of 60 people, including women with chronic asthma (case=30) and healthy women (control=30), aged between 19 and 50 years, who volunteered for the study at Antalya University Health Sciences Training and Research Hospital. General dietary habits, physical activity status, some biochemical, oxidative stress and inflammatory parameters, lung function, nutritional status, and adherence to the Mediterranean diet were analysed in the case and control groups. Dietary intake of antioxidant components was assessed using a quantitative food frequency questionnaire, and adherence to the Mediterranean diet was assessed using the "Mediterranean Diet Adherence Scale". The oxidative stress status of the subjects was assessed by measurement of serum total antioxidant status (TAS), total oxidant status (TOS) and oxidative stress index (OSI) markers and the inflammatory status by measurement of serum IL 6, TNF α and hs CRP levels. Since there was a significant difference in dietary energy intake between the case and control group individuals, the nutrient residual model was applied. According to the nutrient residue model, no significant difference was found between the groups in terms of daily dietary intakes of vitamin A [1784.92 μg; 1709.91 μg], vitamin C [198.94 mg; 213.38 mg], vitamin E [21.61 mg; 20. mg], and zinc [10.06 mg; 10.40 mg], as well as magnesium (365.24 mg; 366.14 mg), selenium [11.32 μg; 11.75 μg], copper (2.08 mg; 2.03 mg), and manganese (4.70 mg; 4.74 mg) minerals, when analyzed (p>0.05). When other dietary components showing antioxidant properties were analyzed, it was determined that only total anthocyanidin intakes were significantly lower in the case group than in the control group [31.74 (18.63-56.69) mg and 52.50 (33.32-97.99) mg, respectively] after the nutrient residue model was applied (p<0.05). No association was found between dietary antioxidant nutrients and the inflammatory parameters IL-6 and TNF-α in women with chronic asthma (p>0.05). However, in the control group, an inverse relationship was found between dietary vitamin C and IL-6 level according to the nutrient residual model (r=-0.442; p<0.05). In addition, a significant and inverse relationship was found between total dietary flavonol intake and TOS (r=-0.384; p<0.05), and a significant and inverse relationship was found between total dietary flavan-3-ol and flavonol intake and OSI in women with chronic asthma (r=-0.377 and r=-0.457, respectively; p<0.05) according to the nutrient residue model in the case group. After adjusting for potential confounders, olive oil consumption was found to significantly reduce the risk of asthma (OR= 0.809, 95% CI: 0.679, 0.963) according to logistic regression analysis. These findings indicate potential differences in the intake of dietary flavonoids and flavonoid-rich foods between asthmatic women and healthy women, which could be related to serum IL-6 and oxidative stress markers. Based on the results of this study, it is recommended to identify modifiable dietary factors that may reduce asthma risk or improve asthma-related outcomes, provide personalized dietary advice, and conduct comprehensive trials. Furthermore, encouraging asthmatic women to consume a healthy diet rich with flavonoids and a variety of nutrients may have a beneficial effect by reducing chronic inflammation and oxidative stress.