Effect of Mediterranean diet and Mediterranean diet plus calorie restriction on cognition, lifestyle, and cardiometabolic health: A randomized clinical trial

Lifestyle Interventions and Innovative Approaches for the Management of Neurodegenerative Disorders in Older Adults-State-Of-The-Art and Future Directions

Aging increases the risk of neurodegenerative diseases (NDs) like Alzheimer's (AD) and Parkinson's (PD), characterized by neuronal loss and cognitive decline. Potential preventive/therapeutic interventions also include lifestyle changes like nutrition & diet, exercise, leisure and social engagement. Here, we discuss several lifestyle interventions for healthy brain aging, and in older adults with NDs. Balanced diets like the Mediterranean and MIND diets can reduce cognitive decline during aging. Long-term use of specific nutrient combinations in medical food may also exert benefits on memory. Metabolic interventions like calorie restriction (CR) and intermittent fasting (IF) have shown potential benefits in aging. However, their effects on cognitive function in older adults were modestly explored and remain unclear. Clinical trials are ongoing to test the cognitive and health outcomes of CR/IF variants in older adults with AD or PD (associated or not with metabolic disorders). We also highlight the role of cognitive reserve (CoR) in delaying dementia symptoms. Engaging in diverse leisure activities like music and bilingualism may enhance CoR and reduce AD risk. Finally, we outline future directions for promoting healthy brain aging through lifestyle interventions (e.g., personalized diets, precision nutrition, synergistic lifestyle approaches, AI-based technologies to monitor the effectiveness of lifestyle practices).

Effect of Mediterranean Diets on Cardiovascular Risk Factors and Disease in Overweight and Obese Adults: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

We systematically evaluated effects of Mediterranean diets (MED) on cardiovascular (CV) disease and risk factors in overweight or obese adults. Five engines and two registries were searched until October 2023 for randomized controlled trials (RCTs) evaluating any type of MED compared to other diets or advice in adults. Outcomes of interest were clinical outcomes and CV risk factors (anthropometric, lipids, blood pressure, glucose metabolism, liver function). Inverse variance random effects models were used for meta-analyses; effects of MED were described as mean differences (MDs) and their 95% confidence intervals (CIs). Quality of evidence (QoE) per outcome was evaluated using GRADE methodology. Twenty-six RCTs (n = 10,352) were included. Four RCTs evaluated only obese patients and 22 evaluated overweight and obese patients. Clinical outcomes were only described in the revised 2018 PREDIMED trial where MED was associated with 35% lower risk of myocardial infarction, stroke, or CV death vs advice (hazard ratio, 0.65; 95% CI, 0.50-0.85). MED significantly reduced the values of body mass index (MD, -0.61 kg/m2; 95% CI, -1.14 to -0.09; 17 RCTs), waist circumference (MD, -2.48 cm; 95% CI, -3.99 to -0.96; 17 RCTs), triglycerides (MD, -7.93 mg/dL; 95% CI, -13.48 to -2.39; 19 RCTs), and fatty liver index (MD, -12.26; 95% CI, -23.96 to -0.56; 3 RCTs) compared with controls. MED did not significantly change any other CV risk factors. QoE was very low for most of the outcomes; 85% of RCTs had some concerns or high risk of bias. In overweight or obese adults, MED significantly decreased body mass index, waist circumference, triglycerides, and fatty liver index score but no other CV risk factors when compared with other diets or advice. There was paucity of data on effects of MED on clinical outcomes.

Systematic evaluation and meta-analysis of the effects of major dietary patterns on cognitive function in healthy adults

PURPOSE

Evidence shows diet promotes brain health. Combining foods and nutrients may have beneficial synergistic effects, but the effects on cognitive function interventions are inconsistent. So, a meta-analysis of RCTs was conducted to examine the specific effects on cognitive function.

METHODS

We searched four databases from creation to April 2023. Eligible randomized controlled trials were identified. A random-effects meta-analysis was used to combine standardized mean differences (SMD) (95% confidence intervals [CI]), and homogeneity tests for a variance were calculated.

RESULTS

A total of 19 studies involving 12,119 participants were included in this systematic review. The dietary intervention group had a positive effect on overall cognitive functioning compared to the control group (SMD = 0.14, 95% CI [0.08, 0.20], P < 0.00001). The dietary intervention improved executive function, processing speed and language skills (SMD = -0.10, 95% CI [-0.17,-0.04], P = 0.002, I2 = 0%), (SMD = -0.16, 95% CI [-0.23,-0.09], P < 0.00001, I2 = 0%), (SMD = 0.10, 95% CI [0.01, 0.20], P = 0.03, I2 = 0%). The dietary intervention had no effect on delayed memory and spatial ability (SMD = 0.04, 95% CI [-0.02, 0.09], P = 0.20, I2 = 0%), (SMD = 0.08, 95% CI [-0.01, 0.16], P = 0.08, I2 = 0%).

CONCLUSION

The Mediterranean diet, a diet with restricted caloric intake, a diet incorporating aerobic exercise, a low-carbohydrate diet, and a healthy lifestyle diet (increased intake of fruits and vegetables, and weight and blood pressure management) appear to have positive effects on cognitively healthy adults, as reflected in their overall cognitive, processing speed, executive, and language functions.

PROSPERO REGISTRATION NUMBER

CRD42023414704.

Effectiveness of exercise interventions, alone or in combination with dietary modifications, on working memory in overweight and obese individuals: A systematic review

This systematic review aimed to establish the effectiveness of exercise interventions, alone or in combination with dietary modifications, on working memory (WM) in individuals living with overweight and obesity. A comprehensive literature search was conducted using the Scopus, PubMed, Springer-Link, RefSeek, and Cochrane Library databases to identify relevant publications up to January 18, 2024. Data on participants' characteristics, intervention settings, and key outcomes related to WM were extracted. The quality of the studies was assessed using the PEDro scale. A total of 15 articles met pre-established inclusion criteria, involving participants across nine countries with a range of 12-125 individuals and ages spanning from 6 to 80 years old. Among the studies analyzed, 10 exclusively investigated exercise interventions, whereas five explored the combined effects. Notably, 70% of the exercise interventions (7 out of 10) exhibited positive improvements in WM. Likewise, 60% of the combined interventions (3 out of 5) demonstrated favorable enhancements in WM. No differences were found between the two protocols. Common features between the protocols were identified and described. Both protocols showed favorable and promising effects on WM in this clinical population. Nonetheless, the limited evidence addressing the combination of exercise and diet in the same research approach reduces the generalizability of the findings. This review offers valuable insights for future clinical and research applications in people with overweight and obesity.

Long-Term Impact of Nutritional Intervention with Increased Polyphenol Intake and Physical Activity Promotion on Oxidative and Inflammatory Profiles in Patients with Metabolic Syndrome

Obesity and overweight pose significant risks to health, contributing to the prevalence of chronic conditions like type 2 diabetes mellitus (T2DM) and cardiovascular diseases (CVD). The current study aimed to assess the impact of a 6-year nutritional and lifestyle intervention on oxidative and inflammatory markers in individuals aged 55 to 75, specifically those at high risk of CVD. A study was carried out in a group of 80 participants with metabolic syndrome (MetS) residing in Mallorca, Spain, who underwent nutritional intervention based on a low-calorie Mediterranean diet (MedDiet) and promotion of physical activity. Before and after the intervention, several parameters including anthropometric data, haematological factors, blood pressure, and physical activity level were measured. Oxidative and inflammatory biomarkers in plasma were analysed. After the 6-year intervention, participants who managed to reduce their body mass index (BMI) had greater reductions in abdominal obesity, waist to heigh ratio (WHtR), diastolic blood pressure, and glucose levels, and increased high density protein cholesterol (HDL-c) compared to those who did not reduce BMI. This higher reduction in BMI was related to reduced energy intake and increased adherence to MedDiet, with greater polyphenol intake, and total physical activity (PA). Furthermore, improvements in oxidative stress and proinflammatory status were observed in participants who reduced their BMI. Significant reductions in the activity of the prooxidant enzyme, myeloperoxidase (MPO), levels of the lipid oxidation marker, malondialdehyde (MDA), and the proinflammatory chemokine, monocyte chemoattractant protein-1 (MCP-1,) were found in those who reduced their BMI. In contrast, participants who did not improve their BMI exhibited higher levels of proinflammatory markers such as MCP-1 and tumour necrosis factor α (TNFα), as well as increased activity of the antioxidant enzyme catalase (CAT). Current findings suggest that an effective way to reduce BMI is a hypocaloric MedDiet combined with tailored physical activity to improve oxidative stress and proinflammatory status, and potentially reducing the risk of CVD.

Short-term effects of Mediterranean diet on nutritional status in adults affected by Osteogenesis Imperfecta: a pilot study

BACKGROUND

Osteogenesis Imperfecta (OI) is a heterogeneous group of connective tissue disorders, characterized by varying degrees of skeletal fragility. Patients experience a range of comorbidities, such as obesity, cardiovascular, and gastrointestinal complications, especially in adulthood. All aspects that could benefit from dietary intervention. The aim of this study was to evaluate the effects of a 6-months restricted Mediterranean Diet (rMD) on nutritional status in adult patients affected by OI. We carried out a 6-months longitudinal pilot study. 14 adults (median age: 35 years; 7 women; 7 OI type III) where recruited in 2019 among the members of As.It.O.I., the Italian Association of Osteogenesis Imperfecta. As.It.O.I. All the evaluations were performed at the University of Milan, Italy. The rMD provided a reduction of 30% from daily total energy expenditure. 45% of calories derived from carbohydrates, 35% from fat and 0.7-1.0 g/kg of body weight from proteins. Comparisons of continuous variables after 6 months of intervention were performed by the paired t-test. All P-values were two-tailed, and p < 0.05 was considered significant.

RESULTS

Patients showed significant improvement in anthropometric measurements (BMI = 30.5 vs 28.1 kg/cm2, p < 0.001; Body Fat % = 32.9 vs 29.9, p = 0.006; Waist circumferences = 83.6 vs 79.6 cm; p < 0.001; Arm Fat Area = 29.8 vs 23.07 cm2; p < 0.011) and energy expenditure (REE/kg = 27.2 vs 29.2 kcal/kg, p < 0.001). Glucose and lipid profiles improved (Δglycemia = - 8.6 ± 7.3 mg/dL, p = 0.003; ΔTC = - 14.6 ± 20.1 mg/dL, p = 0.036; ΔLDL = - 12.0 ± 12.1 mg/dL, p = 0.009). Adherence to the MD significantly increased, moving from a moderate to a strong adherence and reporting an increased consumption of white meat, legumes, fish, nuts, fruits and vegetables.

CONCLUSION

A rMD was effective in improving nutritional status and dietary quality in adults with OI. These results underscores the need to raise awareness of nutrition as part of the multidisciplinary treatment of this disease.

The impact of consuming technologically processed functional foods enriched/fortified with (poly)phenols on cardiometabolic risk factors: a systematic review of randomized controlled trials

Cardiovascular diseases are a major global cause of death and healthcare costs, emphasizing the need for effective prevention and management of cardiometabolic risk factors. One promising approach is the consumption of technologically processed functional foods enriched/fortified with (poly)phenols. The current systematic review aimed to evaluate the human clinical trials evidence on the effect of intake of these foods on reducing the most common cardiometabolic risk factors. 12 randomized controlled studies were included in the systematic review, with varying food intake amounts (27-360 g/day) and (poly)phenol doses (32.5-850 mg/day). These interventions included consumption of functional bakery goods, cereal bars, pasta, chocolate, and yogurt, with supplementation periods spanning from 2 to 52 wk. Several foods, such as green tea extract-fortified rye bread and olive fruit (poly)phenol-fortified yogurt, significantly lowered blood pressure. Flavonoid-enriched chocolate, hydroxytyrosol-fortified bread, and other products influenced glucose metabolism. Additionally, various functional foods were associated with improved blood lipid levels. While these results indicate the health advantages of consuming technologically processed functional foods enriched/fortified with (poly)phenols, caution is warranted due to the scarcity and limitations of existing studies. Further research is needed to confirm and expand upon these results in the prevention and management of cardiometabolic risk factors.

Diversity of Culture Microorganisms from Portuguese Sweet Cherries

Consumers today seek safe functional foods with proven health-promoting properties. Current evidence shows that a healthy diet can effectively alleviate oxidative stress levels and reduce inflammatory markers, thereby preventing the occurrence of many types of cancer, hypertension, and cardiovascular and neurological pathologies. Nevertheless, as fruits and vegetables are mainly consumed fresh, they can serve as vectors for the transmission of pathogenic microorganisms associated with various disease outbreaks. As a result, there has been a surge in interest in the microbiome of fruits and vegetables. Therefore, given the growing interest in sweet cherries, and since their microbial communities have been largely ignored, the primary purpose of this study is to investigate their culturome at various maturity stages for the first time. A total of 55 microorganisms were isolated from sweet cherry fruit, comprising 23 bacteria and 32 fungi species. Subsequently, the selected isolates were molecularly identified by amplifying the 16S rRNA gene and ITS region. Furthermore, it was observed that the communities became more diverse as the fruit matured. The most abundant taxa included Pseudomonas and Ralstonia among the bacteria, and Metschnikowia, Aureobasidium, and Hanseniaspora among the fungi.

Exploring the Effects of a Mediterranean Diet and Weight Loss on the Gut Microbiome and Cognitive Performance in Older, African American Obese Adults: A Post Hoc Analysis

African American adults have a higher prevalence of Alzheimer's dementia (AD) than non-Hispanic Whites. The impact of a Mediterranean Diet (Med Diet) and intentional weight loss (IWL) on the gut microbiome may alter AD risk. A post hoc analysis of the Building Research in Diet and Cognition (BRIDGE) trial was performed to determine whether participation in an 8-month Med Diet lifestyle intervention with (n = 35) or without IWL (n = 31) was associated with changes in gut microbiota structure, abundance, and function and whether these changes were related to changes in cognitive performance. The results showed that family and genus alpha diversity increased significantly in both groups combined (p = 0.0075 and p = 0.024, respectively). However, there were no other significant microbially related within- or between-group changes over time. Also, an increase in Med Diet adherence was significantly associated with a decrease in alpha diversity at the phylum level only (p = 0.049). Increasing alpha diversity was associated with decreasing cognitive performance, but this association was attenuated after controlling for Med Diet adherence. In sum, an 8-month Med Diet lifestyle intervention with or without IWL did not appreciably alter the gut microbiome.