# Drug-Food Interactions with a Focus on Mediterranean Diet
## 4 Discussion  
It is of no debate that a healthy diet and nutrition is essential for good health and shields from several chronic non-communicable diseases, such as cardiovascular heart disease, diabetes, CNS disorders, autoimmune disease and cancer [11; 179; 163; 177; 22; 160; 178] Thus, in the context of optimum healthcare provision is important to support patients as well as the general population to embrace a healthier balanced diet and remain adherent and compliant to it along with their medication [181]. Healthcare providers should be able to educate patients and in the context of precision medicine era, to individualize their consultation so as to empower patients to improve their health and well-being [182; 183; 184]. Med-D remains one of the most valuable and widely studied dietary habits for promoting well-being. The clinical evidence supports that long-term adherence to Med-D is valuable against metabolic disorders and cardiovascular diseases. Numerous studies demonstrate the anti-inflammatory and anti-oxidative properties of constituents found within the Med-D foods against risk factors and pathophysiological mechanisms lowering the risk for developing most of the major non-communicable disorders [2; 6; 8; 23; 28; 185; 186]. All those food products and nutraceuticalals that promote well-being have been the focus of research the recent years for the identification of bioactive compounds that can be related with molecular mechanisms by which dietary components promote health and prevent diseases [187; 188; 189]. On the other hand, these bioactive dietary compounds can share same biological mechanisms with drug molecules and interfere with pharmacological mechanisms modulating the clinical outcome due to DFIs [45]. The DFIs, although seeming to be summarized in a simple clinical question \"shall I take this drug with this food?\" are more than that. DFIs depend on the type and amount of food consumed on daily basis, patient's health status, comorbidities, drug categories that are prescribed, time of drug administration and meal intake, the clinical significance of the DFI and whether it is beneficial or not [50; 52]. [PERSON] et al. in their work [45] described that DFIs can be categorized in three groups: (i) pharmaceutical, (ii) pharmacokinetic and (iii) pharmacodynamic based on the mechanism involved. Alternatively, four types can be considered based on the process prior to systemic concentration. Hence, pre-systemic interactions are referred to as type I ex-vivo interactions or type II modulation of enzyme (subtype a) or carriers (subtype b) and/or other deactivations in GI-track (subtype c). Post-systemic interactions are described as type III for modulation of distribution and metabolism in the body and type IV as modulation of drug's renal or enterohepatic clearance. The latter description omits the PD-DFIs which could be considered as a type V post-systemic phase interaction. This work aimed to provide a literature review regarding DFIs focusing on examples of foods that are included in the Med-D and discuss cases in which they can be related with significant DFIs. DFIs for Med-D food products are associated with modulation of PK processes and primarily with drugs' first pass effect from the GI-track to reach the systemic circulation. The majority the cases discussed refer to type II and III (subtypes a and b) with the addition of PD-effects that can occur for some products (Figure 5). Absorption and metabolism are the two main processes that should be considered when the question comes to food effects for a drug and the main pathways involved are the carrier-mediated transport across membranes and/or the mediated metabolism from Phase I and Phase II enzymes [39; 112].