Health effects of 100% fruit and vegetable juices: evidence from human subject intervention studies

A New Mediterranean Lifestyle Pyramid for Children and Youth: A Critical Lifestyle Tool for Preventing Obesity and Associated Cardiometabolic Diseases in a Sustainable Context

Cardiovascular disease risk factors begin in childhood and track into adulthood, increasing the possibility of impaired cardiometabolic health. Adopting healthy dietary patterns can help curb childhood obesity, a worrisome epidemic problem at present. In the era of personalized nutrition, dietary recommendations should be adapted to different stages of life, including children (older than 3 y) and adolescents. In this study, we present an updated version of the Mediterranean Lifestyle Pyramid addressed to children and adolescents, which may be used as a prevention tool by health professionals, teachers, and stakeholders. This pyramid arises from a consensus position between participants in an International Congress on Mediterranean diet held in Barcelona. During this meeting, after reviewing all literature published, a consensus was reached on the new Mediterranean Lifestyle Pyramid for kids including details such as labels of the pyramid, position of foods, servings, type of foods, and healthy lifestyle habits. All components of the pyramid are supported by the most recent scientifically sound research and are based upon top-level evidence in nutritional sciences. Fruit, vegetables, legumes, nuts, wholegrains, and extra-virgin olive oil continue to be at the basis of the pyramid, but the importance of an adequate intake of fish, dairy products, and meat during these particular ages, when body and brain development occurs, is also considered. The promotion of physical activity, adequate sleep, and good emotional health are emphasized, as well as the consumption of seasonal and local products, and overall sustainability. Improving dietary habits in early stages of life should increase health in adulthood and reduce future incidence of noncommunicable chronic diseases. The Mediterranean diet and its graphic representation in the Lifestyle Pyramid should be a health-fostering tool not only for adults and children but also for the entire planet because it promotes the diversity of species, respect for the earth, and the local economy.

Effects of Vegetable and Fruit Juicing on Gut and Oral Microbiome Composition

BACKGROUND

In recent years, juicing has often been promoted as a convenient way to increase fruit and vegetable intake, with juice-only diets marketed for digestive cleansing and overall health improvement. However, juicing removes most insoluble fiber, which may diminish the health benefits of whole fruits and vegetables. Lower fiber intake can alter the microbiota, affecting metabolism, immunity, and mental health, though little is known about juicing's specific effects on the microbiota. This study addresses this gap by exploring how juicing impacts gut and oral microbiome composition in an intervention study.

METHODS

Fourteen participants followed one of three diets-exclusive juice, juice plus food, or plant-based food-for three days. Microbiota samples (stool, saliva, and inner cheek swabs) were collected at baseline, after a pre-intervention elimination diet, immediately after juice intervention, and 14 days after intervention. Moreover, 16S rRNA gene amplicon sequencing was used to analyze microbiota taxonomic composition.

RESULTS

The saliva microbiome differed significantly in response to the elimination diet (unweighted UniFrac: F = 1.72, R = 0.06, p < 0.005; weighted UniFrac: F = 7.62, R = 0.23, p-value = 0.0025) with a significant reduction in Firmicutes (p = 0.004) and a significant increase in Proteobacteria (p = 0.005). The juice intervention diets were also associated with changes in the saliva and cheek microbiota, particularly in the relative abundances of pro-inflammatory bacterial families, potentially due to the high sugar and low fiber intake of the juice-related products. Although no significant shifts in overall gut microbiota composition were observed, with either the elimination diet or the juice intervention diets, bacterial taxa associated with gut permeability, inflammation, and cognitive decline increased in relative abundance.

CONCLUSIONS

These findings suggest that short-term juice consumption may negatively affect the microbiota.

Development and Validation of the Meiji Nutritional Profiling System per Serving Size

Serving size may be the appropriate reference for calculating food nutritional value. We aimed to assess the nutritional values of Japanese foods based on serving sizes rather than per 100 g by adapting the Meiji Nutritional Profiling System (Meiji NPS). Given the variability in serving sizes across countries, we used Japanese serving sizes to calculate the Meiji NPS scores. We confirmed the convergent validity of the Meiji NPS scores per serving size with the Nutrient-Rich Food Index 9.3 using Spearman's correlation coefficients (r = 0.51, p < 0.001). Food groups recommended by official guidelines, such as pulses, nuts and seeds, fish and seafood, fruits, vegetables, and milk and milk products, scored relatively high. Furthermore, the nutrient density scores of food items with small serving sizes, such as mushrooms, algae, seasonings, and fats and oils, were moderated when calculated by per serving size, despite having considerably higher or lower scores per 100 g. These results indicate that calculating NPS per serving size allows for the assessment of the nutritional value of food items in accordance with actual consumption quantities. Therefore, the Meiji NPS calculated per serving size, alongside the per 100 g version, may be useful for dietary management depending on specific purposes.

Association between sugar-sweetened beverages and pure fruit juice with risk of six cardiovascular diseases: a Mendelian randomization study

BACKGROUND

In observational and prospective cohort studies, intake of sugar-sweetened beverages (SSBs) and pure fruit juice (PFJ) has been associated with cardiovascular disease (CVD). Still, the causality of the connection has not yet been determined. Our objective was to uncover the relationship between SSBs/PFJ and CVD.

METHODS

Genetically predicted causal associations between SSBs/PFJ (obtained in a published genome-wide association study) and six common CVDs (atrial fibrillation (AF), angina, heart failure (HF), acute myocardial infarction, hypertension, and coronary atherosclerosis) were assessed using MR analytic modeling. The primary analysis method utilized was the inverse variance weighted (IVW) method, complemented by additional methods such as the weighted median method, MR Egger regression, Cochran's Q test, MR pleiotropy residual, funnel plot, Bonferroni correction, and others for MR analysis. To ensure the robustness of the findings, F-values were calculated as a complementary test to set looser thresholds for exposing genetic instrumental variables (P < 1e-5).

RESULTS

The results of MR analysis suggested genetically causal associations between SSBs and AF (odds ratio (OR): 1.023; 95% confidence interval (CI) 1.007-1.038; P = 0.0039) as well as between PFJ and angina (OR: 0.968; 95% CI, 0.943-0.993; P = 0.0138) there was genetic causality. However, MR analysis showed no causal association between SSBs/PFJ and other CVD risks.

CONCLUSION

This study suggests that there may be a potential causal relationship between SSBs intake and AF and a causal negative association between PFJ intake and angina.

Comparison of vitamin C and flavanones between freshly squeezed orange juices and commercial 100% orange juices from four European countries

Knowing the true levels of nutrients and dietary bioactives in fruit juices at the point of consumption is key to properly understand their potential health benefits. The objective was to characterise the vitamin C and flavanone content in commercial orange juices consumed in Europe, compared with fresh-squeezed juices. Commercial juices were a rich source of vitamin C (>30% of the Nutrient Reference Value). Vitamin C in fresh-squeezed juices, at the end of their shelf-life, remained 33% higher than the levels found in the commercial juices. Flavanones had similar values from both commercial and fresh juices, except for fresh samples stored for 48 h, where fresh juices had higher values (22.36 mg/100 mL). Thus, orange juices preserve their bioactive compounds during storage, with very little influence of the brand, country, industrial process or storage conditions. Main bioactive compounds in commercial juices are present at nutritionally significant levels to the freshly-squeezed ones.