Nutrition and longevity – From mechanisms to uncertainties

Association between dietary inflammatory index with all-cause and cardiovascular disease mortality among older US adults: A longitudinal cohort study among a nationally representative sample

OBJECTIVE

To investigate the association between DII with all-cause and cardiovascular disease (CVD) mortality among older adults in the U.

S METHODS

This prospective cohort study included older adults with complete DII data and mortality data from the National Health and Nutrition Examination Survey (NHANES) 2001-2018. Mortality outcomes were linked to National Death Index records through 31 December 2019. The multivariate Cox proportional hazards models were performed to evaluate the association between DII and mortality. Restricted cubic spline analyses were used to examine the nonlinear association of DII with all-cause and CVD mortality.

RESULTS

During the median follow-up date of 6.7 years, 4446 all-cause deaths were documented among 10,827 representative older adults, including 1230 CVD deaths. After multivariate adjustment, linear relationships between DII with all-cause mortality (P non-linear = 0.17) and non-linear relationship between DII with CVD mortality (P non-linear = 0.04) were observed. Compared to participants with the lowest quartile of DII scores (-5.28 to≤0.43), the multivariate-adjusted HRs and 95 %CI for participants with higher DII scores were 1.19 (Q2, 95 %CI: 1.08-1.31), 1.28 (Q3, 95 %CI: 1.14-1.44), 1.30 (Q4, 95 %CI: 1.17-1.44) for all-cause mortality (P trend <0.001) and 1.19 (Q2, 95 %CI: 0.99-1.43), 1.34 (Q3, 95 %CI: 1.10-1.62), 1.30 (Q4, 95 %CI: 1.06-1.58) for CVD mortality (P trend < 0.01), respectively.

CONCLUSIONS

In the representative sample of older adults in the U.S, higher DII scores were associated with increased risks of all-cause and CVD mortality.

The significance of caloric restriction mimetics as anti-aging drugs

Aging is an intricate process characterized by the gradual deterioration of the physiological integrity of a living organism. This unfortunate phenomenon inevitably leads to a decline in functionality and a heightened susceptibility to the ultimate fate of mortality. Therefore, it is of utmost importance to implement interventions that possess the capability to reverse or preempt age-related pathology. Caloric restriction mimetics (CRMs) refer to a class of molecules that have been observed to elicit advantageous outcomes on both health and longevity in various model organisms and human subjects. Notably, these compounds offer a promising alternative to the arduous task of adhering to a caloric restriction diet and mitigate the progression of the aging process and extend the duration of life in laboratory animals and human population. A plethora of molecular signals have been linked to the practice of caloric restriction, encompassing Insulin-like Growth Factor 1 (IGF1), Mammalian Target of Rapamycin (mTOR), the Adenosine Monophosphate-Activated Protein Kinase (AMPK) pathway, and Sirtuins, with particular emphasis on SIRT1. Therefore, this review will center its focus on several compounds that act as CRMs, highlighting their molecular targets, chemical structures, and mechanisms of action. Moreover, this review serves to underscore the significant relationship between post COVID-19 syndrome, antiaging, and importance of utilizing CRMs. This particular endeavor will serve as a comprehensive guide for medicinal chemists and other esteemed researchers, enabling them to meticulously conceive and cultivate novel molecular entities with the potential to function as efficacious antiaging pharmaceutical agents.

Sex differences in frailty among older adults

By definition, aging is a natural, gradual and continuous process. On the other hand, frailty reflects the increase in vulnerability to stressors and shortens the time without disease (health span) while longevity refers to the length of life (lifespan). The average life expectancy has significantly increased during the last few decades. A longer lifespan has been accompanied by an increase in frailty and decreased independence in older adults, with major differences existing between men and women. For example, women tend to live longer than men but also experience higher rates of frailty and disability. Sex differences prevent optimization of lifestyle interventions and therapies to effectively prevent frailty. Sex differences in frailty and aging are rooted in a complex interplay between uncontrollable (genetic, epigenetic, physiological), and controllable factors (psychosocial and lifestyle factors). Thus, understanding the underlying causes of sex differences in frailty and aging is essential for developing personalized interventions to promote healthy aging and improve quality of life in older men and women. In this review, we have discussed the key contributors and knowledge gaps related to sex differences in aging and frailty.

[Early life nutrition and immunity]

Introduction

The first 1,000 days of life, from conception to two years of age, are a critical time window for human growth and development, since the interaction of different factors can generate relevant changes in different structures and functions of the organism, both at short and long term. Most of the studies in this area have been carried out in the prenatal and neonatal period. Some of the most relevant factors that can affect immune development at this time are smoking, maternal obesity and inadequate intake of micronutrients during pregnancy. In the case of the postnatal period, breastfeeding is primarily the most important factor related to the nutritional and immunological status of the newborn, also being associated with a protective effect against obesity. Subsequently, the proper introduction of complementary feeding will be essential to offer an adequate percentage of nutrients. Likewise, the intestinal microbiota also plays a key role during this period since it is part of different metabolic, protective, and immunological functions of the host. Fluctuations in homeostasis will condition the appearance of dysbiosis, which is associated with the development of different diseases in childhood, adolescence, and adulthood.

Are pregnancy and parity associated with telomere length? A systematic review

BACKGROUND

Women's reproduction requires increased energy demands, which consequently may lead to cellular damage and aging. Hence, Telomere Length (TL), a biomarker of biological aging and health status may possibly serve as a biomarker of reproductive effort. The aim of this systematic review is to evaluate telomere dynamics throughout pregnancy and the association between parity and TL.

METHODS

A systematic search was conducted across seven databases including CINAHL, Cochrane, PsycINFO, Proquest, PubMed; Scopus; and Web of Science, using keywords and MeSH descriptors of parity and TL. Predefined inclusion and exclusion criteria were used to screen abstracts and titles. After the removal of duplicates, 3431 articles were included in the primary screening, narrowed to 194 articles included in the full-text screening. Consensus was reached for the 14 studies that were included in the final review, and the Newcastle-Ottawa scale (NOS) was utilized to assess the quality of the selected studies. A mini meta-analysis utilized JASP 0.17.3 software and included 4 applicable studies, comprising a total of 2564 participants to quantitatively assess the estimated effect size of parity on TL.

RESULTS

Of the 11 studies reviewed on parity and TL, four demonstrated a negative correlation; one - a positive correlation and six -found no correlation. Studies demonstrating a negative correlation encompassed rigorous methodological practices possibly suggesting having more children is associated with enhanced telomere attrition. Of the four longitudinal studies assessing telomere dynamics throughout pregnancy, most found no change in TL from early pregnancy to postpartum suggesting pregnancy does not affect TL from early pregnancy to early postpartum. The meta-analysis revealed a negative, yet, non-significant effect, of the estimated effect size of parity on TL(ES = -0.009, p = 0.126, CI -0.021, 0.03).

CONCLUSIONS

Studies assessing pregnancy, parity and TL yielded mixed results, most likely due to the different research methods utilized in each study. Improvements in study design to better understand the short-term effects of pregnancy on TL and the effect of parity on TL over time, include precise definitions of parity, comparisons of different age groups, inclusion of reproductive lifespan and statistically adjusting for potential confounders in the parity and TL relationship.

Impact of an Educational Intervention for Healthy Eating in Older Adults: A Quasi-Experimental Study

The elderly population in Ecuador is increasing rapidly, with an increasing incidence of diet-related diseases. The elderly living in the community seek alternative and complementary methods to improve their diet and quality of life. This study aimed to investigate the impact of an educational intervention on knowledge related to healthy eating among older adults. This intervention is rooted in the principles of meaningful learning and incorporates culturally adapted materials. A quasi-experimental study design was employed using a pre-test-post-test control group. Study participants were a total of 109 elderly (intervention: n = 51, control: n = 58) people in Cuenca, Ecuador. The educational intervention based on Ausubel's theory of significant learning and Vygotsky's sociocultural theory was programmed to be carried out for one session per week, over 24 weeks, with a duration of 120 min per session. The measures were the general characteristics of the study participants and knowledge about necessary amounts, food sources and the consequences of deficits or excesses in the consumption of macro- and micronutrients. Data were collected from August 2018 to February 2019. Statistically significant differences were observed between the intervention group (IG) and the control group (CG) in terms of knowledge about healthy eating for older adults following the educational intervention. The outcomes of this study strongly suggest the efficacy of the program in improving knowledge related to healthy eating among older adults. Healthcare providers should prioritize food education based on meaningful learning, utilizing culturally adapted materials for the elderly individuals residing within the community.

Effect of a 3-year lifestyle intervention on telomere length in participants from PREDIMED-Plus: A randomized trial

BACKGROUND & AIMS

Short telomeres have been observed in chronic disease patients. Identifying environmental and lifestyle factors that could reduce telomere attrition is crucial for disease prevention. The aim of this work was to determine whether weight-loss induced by an energy-reduced Mediterranean diet (erMedDiet) and physical activity (PA) could modify telomere length (TL).

METHODS

In 317 randomized non-smoker participants (mean age, 65.8 ± 4.98 years) with metabolic syndrome from two "Prevención con Dieta Mediterránea-Plus" (PREDIMED-Plus) trial centers, we evaluated MedDiet adherence, PA, anthropometric variables and TL at baseline and after a 3-year intervention using an intensive lifestyle program (IG) with an erMedDiet and PA or an unrestricted MedDiet without PA promotion (CG).

RESULTS

Participants in the IG displayed greater 3-year weight reductions (-3.7 ± 4 kg, P < 0.001) compared to those in the CG. No differences in TL changes between groups were observed in the cohort as a whole. However, an interaction was observed between the intervention group and sex for TL changes (pinteraction = 0.039). Women in the IG showed an increase in TL after 3-y (+0.25 ± 0.9, relative units) compared to women in the CG (-0.07 ± 1.0) (pANCOVA = 0.036), whereas no differences between groups were observed in men. Women in the IG had a lower risk of telomere shortening after the intervention (OR = 0.17, 95%CI: 0.05-0.64, p = 0.008) compared to women in the CG.

CONCLUSIONS

A 3-year lifestyle intervention based on an erMedDiet and PA slowed telomere shortening in women but not in men.

TRIAL REGISTRATION

ISRCTN, ISRCTN89898870. Registered 24 July 2014- Retrospectively registered, https://www.isrctn.com/ISRCTN89898870.

The Association Between Census Tract Healthy Food Accessibility and Life Expectancy in the United States

Accessibility of healthy food is an important predictor for several health outcomes, but its association with life expectancy is unclear. We evaluated the association between U.S. Department of Agriculture's Food Research Atlas measures of healthy food accessibility and life expectancy at birth across contiguous U.S. census tracts using spatial modeling analysis. Both income and healthy food accessibility were associated with life expectancy at birth, as indicated by shorter life expectancy in low-income census tracts when comparing tracts with similar healthy food accessibility level, and in low-access tracts when comparing tracts with similar income level. Compared to high-income/high-access census tracts, life expectancy at birth was lower in high-income/low-access (- 0.33 years; 95% confidence interval - 0.42, - 0.28), low-income/high-access (- 1.45 years; - 1.52, - 1.38), and low-income/low-access (- 2.29 years; - 2.38, - 2.21) tracts after adjusting for socio-demographic characteristics and incorporating vehicle availability. Effective interventions to increase healthy food accessibility may improve life expectancy.

Dietary Patterns and Practices and Leucocyte Telomere Length: Findings from the UK Biobank

BACKGROUND

Shorter telomere length (TL) is associated with risk of several age-related diseases and decreased life span, but the extent to which dietary patterns and practices associate with TL is uncertain.

OBJECTIVE

This study aimed to investigate the association of dietary patterns and practices and leucocyte TL (LTL).

DESIGN

This was a cross-sectional study.

PARTICIPANTS AND SETTING

Data collected voluntarily from up to 422,797 UK Biobank participants, during 2006-2010.

MAIN OUTCOME MEASURES

LTL was measured as a ratio of the telomere repeat number to a single-copy gene and was loge-transformed and standardized (z-LTL).

STATISTICAL ANALYSES PERFORMED

Adherence a priori to a Mediterranean-style diet was assessed through the MedDietScore. Principal component analysis was used to a posteriori extract the "Meat" and "Prudent" dietary patterns. Additional dietary practices considered were the self-reported adherence to "Vegetarian" diet, "Eating 5-a-day of fruit and vegetables" and "Abstaining from eggs/dairy/wheat/sugar." Associations between quintiles of dietary patterns or adherence to dietary practices with z-LTL were investigated through multivariable linear regression models (adjusted for demographic, lifestyle, and clinical characteristics).

RESULTS

Adherence to the "Mediterranean" and the "Prudent" patterns, was positively associated with LTL, with an effect magnitude in z-LTL of 0.020 SD and 0.014 SD, respectively, for the highest vs the lowest quintile of adherence to the pattern (both P values < 0.05). Conversely, a reversed association between quintile of the "Meat" pattern and LTL was observed, with z-LTL being on average shorter by 0.025 SD (P = 6.12×10-05) for participants in the highest quintile of the pattern compared with the lowest quintile. For adherents to "5-a-day" z-LTL was on average longer by 0.027 SD (P = 5.36×10-09), and for "abstainers," LTL was shorter by 0.016 SD (P = 2.51×10-04). The association of LTL with a vegetarian diet was nonsignificant after adjustment for demographic, lifestyle, and clinical characteristics.

CONCLUSIONS

Several dietary patterns and practices associated with beneficial health effects are significantly associated with longer LTL. However, the magnitude of the association was small, and any clinical relevance is uncertain.

Socioeconomic differences in animal food consumption: Education rather than income makes a difference

Background/aims

Evidence points toward more sustainable and health-conscious dietary behaviors among individuals with higher socioeconomic status. However, these differences vary considerably depending on which indicator of socioeconomic status is examined. Here, we present a systematic parallel investigation of multiple indicators of socioeconomic status as predictors of animal food consumption frequency and selected food-related behaviors in Germany.

Methods

Data from the German subsample of two large representative European consumer studies (Study 1 n = 1,954; Study 2 n = 2,045) was used. We assessed the associations between the socioeconomic indicators income, current occupation as well as education and consumption frequency of animal foods and selected food-related behaviors in separate ordinal logistic regressions.

Results

Individuals with higher educational attainment engaged in more sustainable and health-conscious dietary behaviors, indicated by significant associations between educational attainment and the consumption frequency of animal foods. Low- and middle-income participants consumed processed meat more frequently (Study 1 only; medium income: OR 1.5, CI 1.09-2.05, p = 0.012; low income: OR 1.43, CI 1.01-2.05, p = 0.047) and fish less frequently (Study 2 only; medium income: OR 0.76, CI 0.59-0.97, p = 0.026; low income: OR 0.061, CI 0.46-0.82, p < 0.001) than participants with high income. Current occupation did not predict the consumption of animal foods or food-related behaviors. Intake frequency of animal-based foods indicates that most participants exceeded national dietary recommendations for meat and processed meat and remained below recommendations for fish and dairy/eggs intake.

Conclusion

Educational attainment appears to be the strongest and most consistent socioeconomic indicator of sustainable dietary choices in Germany based on current large, representative studies. Future efforts should be directed toward education interventions about nutrition and interpretation of food labels to compensate for differences in dietary behavior among groups with different levels of education.

Mathematical Modeling and Optimization of Lactobacillus Species Single and Co-Culture Fermentation Processes in Wheat and Soy Dough Mixtures

To improve food production via fermentation with co-cultures of microorganisms (e.g., multiple lactic acid bacteria-LAB strains), one must fully understand their metabolism and interaction patterns in various conditions. For example, LAB can bring added quality to bread by releasing several bioactive compounds when adding soy flour to wheat flour, thus revealing the great potential for functional food development. In the present work, the fermentation of three soy and wheat flour mixtures is studied using single cultures and co-cultures of Lactobacillus plantarum and Lactobacillus casei. Bio-chemical processes often require a significant amount of time to obtain the optimal amount of final product; creating a mathematical model can gain important information and aids in the optimization of the process. Consequently, mathematical modeling is used to optimize the fermentation process by following these LAB’s growth kinetics and viability. The present work uses both multiple regression and artificial neural networks (ANN) to obtain the necessary mathematical model, useful in both prediction and process optimization. The main objective is to find a model with optimal performances, evaluated using an ANOVA test. To validate each obtained model, the simulation results are compared with the experimental data.

Fungal-Derived Mycoprotein and Health across the Lifespan: A Narrative Review

Mycoprotein is a filamentous fungal protein that was first identified in the 1960s. A growing number of publications have investigated inter-relationships between mycoprotein intakes and aspects of human health. A narrative review was undertaken focusing on evidence from randomized controlled trials, clinical trials, intervention, and observational studies. Fifteen key publications were identified and undertaken in early/young adulthood, adulthood (mid-life) or older/advanced age. Main findings showed that fungal mycoprotein could contribute to an array of health benefits across the lifespan including improved lipid profiles, glycaemic markers, dietary fibre intakes, satiety effects and muscle/myofibrillar protein synthesis. Continued research is needed which would be worthwhile at both ends of the lifespan spectrum and specific population sub-groups.

DIet and Health From reGIstered Trials on ClinicalTrials.gov: The DIGIT Study

Background

Clinical trial registration has become a valuable tool that can be used to track the status and nature of trials conducted on a specific topic. This approach has been applied to many areas of research, but less is known about the characteristics and trends over time of clinical trials focused on diet and health. The aim of this study was to analyze diet-related clinical trials registered on the National Institute of Health “ClinicalTrials.gov” web platform in the last 10 years, to list and describe their characteristics, and to identify possible gaps to be filled in the future research.

Methods

A search was performed on the ClinicalTrials.gov database. Intervention studies registered from January 2010 to December 2020, conducted on adults, with a follow-up of ≥2 weeks, evaluating the impact of different diets on all outcomes except those assessed with scales or questionnaires were considered.

Results

At the end of the selection process, a total of 1,016 registered clinical trials were identified and included in the analysis. The most investigated dietary approaches were balanced diets (n = 381 trials), followed by those based on a modification of macronutrients (n = 288) and time-restricted feeding and intermittent fasting diets (n = 140). The main measured outcomes included anthropometric parameters and body composition (57.8%), glycemic control parameters (49.7%), lipid parameters (40.1%), inflammatory markers (29.1%), and blood pressure and/or heart rate (24.5%). A growing body of studies also focused on microbiota and host metabolism (17.8%). Most studies had a duration of less than 12 weeks (~60%), and more than 90% of studies enrolled volunteers with overweight/obesity or other diseases. Regarding aging, only 21 studies focused only on older adults.

Conclusion

The number of studies investigating the relationship between diet and health has increased over the years. Despite the growing interest in the topic, there are some gaps, such as the limited duration of most trials, the underrepresentation of some population groups, and the limited number of studies for some diets that, although popular in the population, lack robust scientific evidence.

Rebalancing the unbalanced aged immune system - A special focus on zinc

Nowadays, aging is understood as a dynamic and multifaceted dysregulation process that spares almost no human organ or cell. The immune system being among the most affected, it has been shown predominantly that its integrity determines the tightrope walk between the difference of escaping or suffering from age-related diseases. Next to drug-based anti-aging strategies, micronutrient intervention may represent an emerging but less radical way to slow immune aging. While a sufficient supply of a variety of micronutrients is undeniably important, adequate intake of the trace element zinc appears to tower over others in terms of reaching old age. Inconveniently, zinc deficiency prevalence among the elderly is high, which in turn contributes to increased susceptibility to infection, decreased anti-tumor immunity as well as attenuated response to vaccination. Driven by this research, this review aims to provide a comprehensive and up-to-date overview of the various rebalancing capabilities of zinc in the unbalanced immune system of the elderly. This includes an in-depth and cell type-centered discussion on the role of zinc in immunosenescence and inflammaging. We further address upcoming translational aspects e.g. how zinc deficiency promotes the flourishing of certain pathogenic taxa of the gut microbiome and how zinc supply counteracts such alterations in a manner that may contribute to longevity. In the light of the ongoing COVID-19 pandemic, we also briefly review current knowledge on the interdependency between age, zinc status, and respiratory infections. Based on two concrete examples and considering the latest findings in the field we conclude our remarks by outlining tremendous parallels between suboptimal zinc status and accelerated aging on the one hand and an optimized zinc status and successful aging on the other hand.

Epidemiological and genetic overlap among biological aging clocks: New challenges in biogerontology

Estimators of biological age (BA) - defined as the hypothetical underlying age of an organism - have attracted more and more attention in the last years, especially after the advent of new algorithms based on machine learning and genetic markers. While different aging clocks reportedly predict mortality in the general population, very little is known on their overlap. Here we review the evidence reported so far to support the existence of a partial overlap among different BA acceleration estimators, both from an epidemiological and a genetic perspective. On the epidemiological side, we review evidence supporting shared and independent influence on mortality risk of different aging clocks - including telomere length, brain, blood and epigenetic aging - and provide an overview of how an important exposure like diet may affect the different aging systems. On the genetic side, we apply linkage disequilibrium score regression analyses to support the existence of partly shared genomic overlap among these aging clocks. Through multivariate analysis of published genetic associations with these clocks, we also identified the most associated variants, genes, and pathways, which may affect common mechanisms underlying biological aging of different systems within the body. Based on our analyses, the most implicated pathways were involved in inflammation, lipid and carbohydrate metabolism, suggesting them as potential molecular targets for future anti-aging interventions. Overall, this review is meant as a contribution to the knowledge on the overlap of aging clocks, trying to clarify their shared biological basis and epidemiological implications.

Metabolomics Study of Isocaloric Different Dietary Patterns on the Life Span in Healthy Population

Purpose

How to prolong life by diet has been widely concerned. There are many reports about the effects of different dietary patterns on life span, but the results are not consistent. The main reason may be that total energy intake has not been considered. This study aims to explore the effects of isocaloric different dietary patterns on population life span.

Materials and Methods

From the data of the follow-up population, eligible participators were divided into normal control (NC) group (28.31% fat, 12.37% protein, 62.30% carbohydrate), isocaloric high-fat (IHF) group (38.39% fat, 12.21% protein, 51.32% carbohydrate), isocaloric high-protein (IHP) group (33.41% fat, 17.10% protein, 52.67% carbohydrate) and isocaloric high-carbohydrate (IHC) group (22.23% fat, 10.52% protein, 70.13% carbohydrate) according to the dietary structure and the age stratification. Global serum metabolic profiling analysis by UPLC−Q-TOF-MS/MS technology, fatty acid and amino acid profiles in serum were determined by GC-MS and UPLC-TQ-MS technology. One-way ANOVA followed by Dunnett post hoc test and receiver operating characteristic (ROC) curve analysis were used to statistical analysis.

Results

Non-targeted metabolomics was to identify 18 potential metabolites related to longevity. ROC curve analysis to identify biomarkers indicated that the areas under the ROC (AUC) of the 12 of 18 biomarkers are above 0.9. The 12 biomarkers were mainly enriched in three metabolic pathways: lipid metabolism, amino acid metabolism and tricarboxylic acid cycle. Compared to control, 11 and 10 of 12 biomarkers showed the same trend with aging in IHP and IHC groups, respectively. Conversely, no differences were observed between IHF group and NC group.

Conclusion

Without consideration of the nature of carbohydrates, fats and proteins, IHP and IHC diets might shorten life span by influencing amino acid metabolism, lipid metabolism and tricarboxylic acid cycle metabolism, while the isocaloric IHF diet has no effects on longevity.

Complementary and Alternative Therapies for Weight Loss: A Narrative Review

Despite various strategies, overweight and obesity problems are still increasingly prevalent worldwide with serious health outcomes. Consequently, the continuous demand for more effective, safe and acceptable therapies for reducing body weight is also escalating—including complementary and alternative therapies (CATs). The aim of this review is to provide a summary of the most commonly- and recently-used CATs, with evaluation of their safety and efficacy for weight loss. Electronic scientific databases such as Scopus, PubMed and EBSCO Host were explored for articles that reported CATs for overweight and obesity treatment from 2015 to December 2019. Only systematic reviews, meta-analysis and randomized controlled trials (RCTs) published in English were included. Studies whereby CATs were not utilized for reducing body weight were excluded. Eight systematic reviews and meta-analyses and 11 additional RCTs with 765 participants (50.2% overweight and 49.8% obese) related to hypnotherapy, acupuncture and dietary supplements met the inclusion criteria. Their results suggested that spirulina, chitosan, probiotic, EPA + DHA, vitamin D, fiber, and herbal extract supplementation may all provide small reductions in body weight (ranging from 1-10 kg). Interestingly, hypnotherapy and acupuncture reported significantly greater reduction in body weight compared with placebo (p < 0.001 and p < 0.0001, respectively). Nonetheless, the evidence is still relatively limited and not encouraging to provide a definitive conclusion due to the methodological shortcomings and the presence of adverse events in chitosan and fiber supplementation. Hence, studies of this nature need to be further replicated and improved to corroborate the efficacy and safety of the CATs to combat weight issues.

Whole-Grain Intake in the Mediterranean Diet and a Low Protein to Carbohydrates Ratio Can Help to Reduce Mortality from Cardiovascular Disease, Slow Down the Progression of Aging, and to Improve Lifespan: A Review

Increase in the aging population is a phenomenon all over the world. Maintaining good functional ability, good mental health, and cognitive function in the absence of severe disease and physical disability define successful aging. A healthy lifestyle in middle age predisposes successful aging. Longevity is the result of a multifactorial phenomenon, which involves feeding. Diets that emphasize fruit and vegetables, whole grains rather than refined grains, low-fat dairy, lean meats, fish, legumes, and nuts are inversely associated with mortality or to a lower risk of becoming frail among elderly subjects. A regular physical activity and a regular intake of whole grain derivatives together with the optimization of the protein/carbohydrate ratio in the diet, where the ratio is significantly less than 1 such as in the Mediterranean diet and the Okinawan diet, reduces the risk of developing aging-related diseases and increases healthy life expectancy. The purpose of our review was to analyze cohort and case-control studies that investigated the effects of cereals in the diet, especially whole grains and derivatives as well as the effects of a diet with a low protein-carbohydrate ratio on the progression of aging, mortality, and lifespan.

Casting iron into the cell fate mold

This commentary discusses general concepts introduced in the article 'Bulk autophagy induction and life extension is achieved when iron is the only limited nutrient in Saccharomyces cerevisiae' by Montella-Manuel et al. (Biochem J (2021) 478: 811-837). Montella-Manuel et al. show that like central carbon metabolism, iron metabolism is also closely implicated in autophagy-mediated life extension via the TORC2 activator Ypk1p and the iron regulator Aft1p. While not being an iron-sulfur cluster protein, Aft1p interacts with such proteins and thus senses the redox status of the cell, which, similar to amino acids and AMP, reports its energetic status. Furthermore, glucose and iron deficiencies are interrelated as the diauxic shift in glucose depleted cells requires iron uptake for activating respiration in the absence of fermentation.

Vegetarian Diet: An Overview through the Perspective of Quality of Life Domains

Vegetarianism has gained more visibility in recent years. Despite the well-described effects of a vegetarian diet on health, its influence on the quality of life of the individuals who follow it still needs to be properly investigated. Quality of life relates to a subjective perception of well-being and functionality, and encompasses four main life domains: physical, psychological, social, and environmental. The adoption of a vegetarian diet, despite being a dietary pattern, could potentially influence and be influenced by all of these domains, either positively or negatively. This review aims to present an overview of the background, conceptualization, features, and potential effects of vegetarianism in all quality of life domains. The choice of adopting a vegetarian diet could have positive outcomes, such as better physical health, positive feelings related to the adoption of a morally correct attitude, an increased sense of belonging (to a vegetarian community), and lower environmental impact. Other factors, however, could have a negative impact on the quality of life of those choosing to abstain from meats or other animal products, especially when they go beyond one's control. These include the environment, the social/cultural group in which a person is inserted, gender-based differences, economic aspects, and a limited access to a wide variety of plant-based foods. It is important to understand all the effects of adopting a vegetarian diet-beyond its nutritional aspects. Not only do studies in this area provide more consistent data, but they may also contribute to mitigating all factors that might prevent individuals from adopting a vegetarian diet, or that may have a negative impact on the quality of life of those who already follow it.

Macronutrient Quality and All-Cause Mortality in the SUN Cohort

No previous study has assessed the relationship between overall macronutrient quality and all-cause mortality. We aimed to prospectively examine the association between a multidimensional macronutrient quality index (MQI) and all-cause mortality in the SUN (Seguimiento Universidad de Navarra) (University of Navarra Follow-Up) study, a Mediterranean cohort of middle-aged adults. Dietary intake information was obtained from a validated 136-item semi-quantitative food-frequency questionnaire. We calculated the MQI (categorized in quartiles) based on three quality indexes: the carbohydrate quality index (CQI), the fat quality index (FQI), and the healthy plate protein source quality index (HPPQI). Among 19,083 participants (mean age 38.4, 59.9% female), 440 deaths from all causes were observed during a median follow-up of 12.2 years (IQR, 8.3–14.9). No significant association was found between the MQI and mortality risk with multivariable-adjusted hazard ratio (HR) for the highest vs. the lowest quartile of 0.79 (95% CI, 0.59–1.06; P_trend = 0.199). The CQI was the only component of the MQI associated with mortality showing a significant inverse relationship, with HR between extreme quartiles of 0.64 (95% CI, 0.45–0.90; P_trend = 0.021). In this Mediterranean cohort, a new and multidimensional MQI defined a priori was not associated with all-cause mortality. Among its three sub-indexes, only the CQI showed a significant inverse relationship with the risk of all-cause mortality.

Recent advances in the field of caloric restriction mimetics and anti-aging molecules

Caloric restriction (CR) mimetics are molecules that produce beneficial effects on health and longevity in model organisms and humans, without the challenges of maintaining a CR diet. Conventional CR mimetics such as metformin, rapamycin and spermidine activate autophagy, leading to recycling of cellular components and improvement of physiological function. We review here novel CR mimetics and anti-aging compounds, such as 4,4'-dimethoxychalcone, fungal polysaccharides, inorganic nitrate, and trientine, highlighting their possible molecular targets and mechanisms of action. The activity of these compounds can be understood within the context of hormesis, a biphasic dose response that involves beneficial effects at low or moderate doses and toxic effects at high doses. The concept of hormesis has widespread implications for the identification of CR mimetics in experimental assays, testing in clinical trials, and use in healthy humans. We also discuss the promises and limitations of CR mimetics and anti-aging molecules for delaying aging and treating chronic diseases.

Nutrients and Pathways that Regulate Health Span and Life Span

Both life span and health span are influenced by genetic, environmental and lifestyle factors. With the genetic influence on human life span estimated to be about 20–25%, epigenetic changes play an important role in modulating individual health status and aging. Thus, a main part of life expectance and healthy aging is determined by dietary habits and nutritional factors. Excessive or restricted food consumption have direct effects on health status. Moreover, some dietary interventions including a reduced intake of dietary calories without malnutrition, or a restriction of specific dietary component may promote health benefits and decrease the incidence of aging-related comorbidities, thus representing intriguing potential approaches to improve healthy aging. However, the relationship between nutrition, health and aging is still not fully understood as well as the mechanisms by which nutrients and nutritional status may affect health span and longevity in model organisms. The broad effect of different nutritional conditions on health span and longevity occurs through multiple mechanisms that involve evolutionary conserved nutrient-sensing pathways in tissues and organs. These pathways interacting each other include the evolutionary conserved key regulators mammalian target of rapamycin, AMP-activated protein kinase, insulin/insulin-like growth factor 1 pathway and sirtuins. In this review we provide a summary of the main molecular mechanisms by which different nutritional conditions, i.e., specific nutrient abundance or restriction, may affect health span and life span.

Nutritional status as a predictor of adverse events and survival in pediatric autologous stem cell transplant

Nutritional status is recognized as an independent and modifiable risk factor of outcome in stem cell transplant. Our research aim was to evaluate the impact of body mass index (BMI) and serum albumin on the prevalence of adverse events and survival in autologous transplant in children. A retrospective study was conducted of autologous transplants performed between 2006 and 2017 in the Children's Hospital Zagreb, Croatia. Nutritional status was assessed at the times of diagnosis, procedure, and discharge using BMI (underweight, normal, obese) and serum albumin (grades 1-4). Adverse events (fever, gastrointestinal toxicity, electrolyte disturbances, dysglycemia) and outcome (3-year, relapse, mortality) were documented. Seventy-seven children (54.5% males, mean age 7.9 years) underwent autologous transplant, mostly for neuroblastoma. In terms of BMI and albumin, which showed significant positive correlation at diagnosis (p = 0.026) and transplant (p = 0.016), most participants were well nourished. Average post-transplant weight loss was 4%. Major toxicities were severe mucositis (72.7%) and hypophosphatemia (31.2%). Relapse and mortality rates were 35.1% and 42.9%, respectively. Hypokalemia (p = 0.041) and hypomagnesemia (p = 0.044) were more prevalent in the underweight group, while obese children experienced significantly less severe mucositis (p = 0.016) and hypophosphatemia (p = 0.038). There was no significant difference regarding outcome among children of different nutritional status, although undernourished children tended to have lower relapse and mortality rates. In conclusion, underweight children are significantly more prone to severe electrolyte disorders and mucositis, and although statistical significance was not reached, are more likely to survive.