The MedDiet
[71][72][73], or its components
[74][75], RCD, allied to daily consumption of GSE
[76], DASH patterns
[77], LFHC diet
[78], the Baltic Sea diet
[79], the Nordic diet
[80], SEAD
[81], the KEMEPHY diet
[82], or the use of EDI scores to assess MedDiet adherence
[83], promoted decreased inflammatory markers and improved cardiometabolic risk factors (
Figure 12), including components that belong to MetS. MetS is one of the most significant risk factors associated with CVD
[84][85] and it is defined as having at least three of the following characteristics: (i) central obesity, (ii) increased serum triglyceride levels, (iii) low HDL levels in the blood, (iv) cholesterol levels, (v) hypertension, and (vi) higher fasting blood glucose levels
[85]. Since these diets are very similar, this might explain the similar results. In several studies, researchers note that the MedDiet is able to prevent CVD
[20][22][86][87]; this effect is due to the combination of different foods that have anti-inflammatory properties. The DASH diet pattern was already established as a potential treatment for hypertension
[88], to reduce both fasting and postprandial insulin concentrations
[89], and CRP levels
[90][91]. The KEMEPHY diet, by inducing a physiological ketosis through elevated ketone bodies present in blood or urine
[92], stimulates positive changes in cardiovascular risk factors and body composition
[93].
SEAD, just like the MedDiet, is rich in folate and vitamin C from vegetables, as well as omega-3 fatty acids from fish; these compounds have already been connected with reduced insulin
[94][95] and low hs-CRP
[96]. This inflammatory marker was also reduced in this diet, suggesting that it may reduce CVD risk (
Figure 12). The Baltic Sea diet also promotes the reduction of CRP concentrations (
Figure 12), due to the presence of Nordic fruits and berries and cereals
[79]. They contain antioxidant components, such as polyphenols, minerals, vitamins, and dietary fibers, which diminish these levels and the release of E-selectin
[97][98]. This molecule is produced and released into circulation during endothelial injury, and its reduction improves endothelial function
[98]. The healthy Nordic diet decreases IL-1 Ra
[80], which is one of the most sensitive inflammatory markers, in obesity and MetS. It has been associated with high intakes of SFAs and lower consumption of berries, fruits, and whole-grain products
[99][100][101]. Moreover, higher levels of IL-1 Ra have been revealed to predict T2D and the progression of MetS to T2D
[99]. In addition, this healthy Nordic diet promotes the reduction of non-HDL-C and LDL-C, which are designated to have an important impact on CVD morbidity and mortality
[102][103]. CVD risk is also attenuated by high intakes of potassium (
Figure 12) due to its nonlinear association with CVD biomarkers (
Figure 12)
[104][105][106], which is supported by previous studies
[107][108][109], thus endorsing the World Health Organization (WHO) recommendation that adults increase their potassium intake
[110]. In contrast, CVD, IHD/cerebrovascular disease, and all-cause mortality was linked to UPF consumption
[40][111][112][113].
The MedDiet also decreases risk factors associated with other comorbidities (
Figure 23), such as hepatic steatosis
[72], atherothrombosis
[114], oxidative stress, by promoting the excretion of urinary metabolites
[115], and, allied to virgin olive oil, demonstrates protective effects on bone tissue, by increasing serum osteocalcin
[116].
The MedDiet, allied to a supplementation of CoQ, was shown to protect DNA from oxidative damage (
Figure 23) by reducing the activation of p53
[117] and, consequently, the expression of genes involved in p53-dependent DNA repair were downregulated
[118]. Previous studies demonstrated that DNA damage plays an important role in the pathogenesis of atherosclerosis (buildup of fats, cholesterol, and other substances in and on the artery walls), as well as other aging-related diseases
[119]. As for diets rich in PUFAs—CoQ supplements have been shown to mitigate oxidative and lipid peroxidation chain reaction damage
[120][121], regenerate other antioxidants, such as α-tocopherol and ascorbate
[122][123][124], and reduce CVD risk and inflammation
[120]. The fatty acid content of cellular membranes and fluids is linked to oxidative stress, so it was expected that MedDiet + CoQ helped prevent this event
[125][126][127]. Furthermore, recent research has shown that changes in the expression of p53 and the p53-regulated DNA damage response genes, such as
gadd45a and
mdm2, can be used as genotoxic and carcinogenic stress markers
[128][129]. This diet also has an additional influence on the inflammatory response and ER stress
[130], since it reduces the p65, IKK-b, and IL-1b gene expression.
A low-fat diet rich in fibers has demonstrated protective effects on periodontal disease (
Figure 23), by reducing its biomarkers in older adults
[131]. This disease has already been associated with obesity
[91][132].
In contrast, previous studies
[133][134][135][136][137][138][139] have demonstrated that unhealthy habits, such as westernized diets (high intakes of red meat, processed foods, ‘
‘fast-foods
’’, high-fat dairy products, snacks, and sugary soft drinks, and low intakes of fruits, vegetables, vitamins, and minerals), lack of physical activity, alcohol consumption, or smoking can potentiate the risk of development of diabetes, obesity, cardiovascular diseases, and cancer. Thus, even in the absence of traditional CVD risk factors (smoking, T2D, high BP, and elevated levels of cholesterol), weight-loss strategies should always be recommended in order to keep a healthy body weight to decrease CVD and other comorbidities risk.
3. Conclusions
Diets rich in vegetables, fruits, nuts, cereals, fibers, fish, unsaturated fats, containing antioxidants, vitamins, potassium, omega-3—and reducing red meat and UPF intake—could prevent obesity, CVD, and inflammation, and promote favorable glycemic, insulinemic, and lipidemic responses. Moreover, the MedDiet and KD, or a combination of these diets (MMKD), and increasing consumption of vegetables and green tea catechins, could improve one‘s working memory and decrease destabilization of the brain network and the attention domain, preventing cognitive decline. Finally, the MedDiet, supplemented with CoQ or VOO, or a low-fat diet, also rich in antioxidants, could help to decrease the prevalence of atherothrombosis, hepatic steatosis, diabetes, and telomere attrition, as well as prevent oxidative and DNA damage. These diets can enhance one‘s quality of life and increase life expectancy. Moreover, a putative panel of molecular markers (see Figure 12 and Figure 23) would follow the impact of diet/nutrition alterations during aging.