## 4 Discussion  
The present study is an original investigation to verify the effect of antioxidant snacks intake and a regular diet on the glutathione-related antioxidant defence system expressed by GPx and GST. To our best knowledge, this is the first study to apply a customised DI in CVD patients and evaluate its effectiveness in promoting their nutritional habits, particularly healthy snacking, to increase diet antioxidant capacity. Following the aim of this project, we established that high-antioxidant snacks, such as juice or vegetable crisps, might enhance the body's antioxidant capacity. We observed significant (\(p<0.01\)) improvement in the GPx and decrease in the GST (0.05) following changes in daily dietary snacking with either a 15 g package of beetroot crisps or a 330 mL bottle of chokeberry juice. This modification increased the participant's diet antioxidant capacity by 48% (CVD) and 24% (CON) in relation to their habitual consumption and resulted in a 32% decrease in GST and a 13% increase in GPx blood concentration. First, it should be noted that despite the increase in the diet antioxidant capacity in both groups, changes were observed only in the group with CVD. This group presented significantly higher levels of GST (\(p<0.01\)) and GPx (\(p<0.01\)) at the beginning of the intervention. In addition, the diet analysis in both groups also showed that the CVD subjects had a higher energy density related to the supply of saturated fat, protein, cholesterol and sodium, significantly reducing the body's antioxidant capacity. This poor diet quality was \begin{table}
\begin{tabular}{c c c} \hline \hline
**Variables** & **CVD** & **CON** \\ \hline ORAC (\(\mu\)MTx/day) & 1924 \(\pm\) 654 & 4865 \(\pm\) 1865 ** \\ ORAC\({}_{\text{snacks}}\) (\(\mu\)MTx/day) & 924 \(\pm\) 154 & 973 \(\pm\) 92 \\ Energy (kcal) & 2420 \(\pm\) 355 & 2087 \(\pm\) 681 * \\ Proteins (in total) (g) & 97 \(\pm\) 47 & 64.5 \(\pm\) 19.4 * \\ Total fats (g) & 111 \(\pm\) 39 & 79.1 \(\pm\) 29.2 * \\ \% energy from proteins & 12.8 \(\pm\) 1.4 & 10.6 \(\pm\) 1.6 \\ \% energy from fats & 36.9 \(\pm\) 8.7 & 26.0 \(\pm\) 3.4 \\ \% energy from carbohydrates & 50.2 \(\pm\) 8.7 & 49.7 \(\pm\) 4.0 \\ Saturated fatty acids SFA (g) & 35.6 \(\pm\) 29.8 & 28.7 \(\pm\) 13.2 ** \\ Monounsaturated fatty acids MUFA (g) & 45.5 \(\pm\) 29.5 & 27.1 \(\pm\) 12.7 ** \\ Polyunsaturated fatty acids PUFA (g) & 22.2 \(\pm\) 16 & 17.1 \(\pm\) 7 \\ Cholesterol (mg) & 359 \(\pm\) 187 & 220 \(\pm\) 76 ** \\ Total carbohydrates (g) & 315 \(\pm\) 142 & 302 \(\pm\) 93 \\ Fibre (g) & 28.2 \(\pm\) 11 & 23.6 \(\pm\) 7.8 \\ Sodium (mg) & 3159 \(\pm\) 810 & 1689 \(\pm\) 169 ** \\ Potassium (mg) & 54,951 \(\pm\) 333 & 3738 \(\pm\) 1484 ** \\ Calcium (mg) & 567 \(\pm\) 188 & 601 \(\pm\) 342 \\ Phosphorus (mg) & 1386 \(\pm\) 509 & 1246 \(\pm\) 382 \\ Magnesium (mg) & 368.6 \(\pm\) 131 & 337 \(\pm\) 96 \\ Iron (mg) & 14.1 \(\pm\) 6.0 & 11.7 \(\pm\) 3.0 \\ Zinc (mg) & 12.9 \(\pm\) 5.5 & 10.1 \(\pm\) 2.3 \\ Vitamin A (retinol equivalent) (\(\mu\)g) & 1488 \(\pm\) 651 & 896 \(\pm\) 300 ** \\ Vitamin D (\(\mu\)g) & 5.4 \(\pm\) 2.5 & 2.5 \(\pm\) 0.7 \\ Vitamin E (alpha-tocopherol equivalent) (\(\mu\)g) & 18.5 \(\pm\) 5.8 & 2.5 \(\pm\) 0.7 \\ Thiamine B1 (mg) & 1.5 \(\pm\) 0.8 & 1.2 \(\pm\) 0.6 \\ Riboflavin B2 (mg) & 1.5 \(\pm\) 0.6 & 1.4 \(\pm\) 0.5 \\ Niacin B3 (mg) & 19.1 \(\pm\) 5.9 & 14.7 \(\pm\) 6.4 \\ Pyridoxine B6 (mg) & 2.5 \(\pm\) 0.9 & 2.1 \(\pm\) 0.9 \\ Foldates (\(\mu\)g) & 369 \(\pm\) 149 & 191 \(\pm\) 49.5 \\ Cyancobalamin B12 (\(\mu\)g) & 4.3 \(\pm\) 2.6 & 3.3 \(\pm\) 1.5 \\ Vitamin C (mg) & 149.1 \(\pm\) 34.6 & 81.7 \(\pm\) 70.2 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Dietary intake of the study sample during 2 nd phase of the DI and CON group. confirmed by assessing their antioxidant capacity without antioxidant snacks. These factors may have contributed to the higher initial levels of oxidative stress in CVD patients and caused them to respond to the inclusion of antioxidant snacks in their diet.