Adult height, dietary patterns, and healthy aging

Sedentary Behaviors, Light-Intensity Physical Activity, and Healthy Aging

Importance

Sleep duration and moderate-to-vigorous physical activity (MVPA) are associated with healthy aging, but the associations of sedentary behaviors and light-intensity physical activity (LPA) with healthy aging are still unclear.

Objective

To examine the independent association of sedentary behaviors and LPA with healthy aging, and to estimate the theoretical association of replacing sedentary behavior with LPA, MVPA, or sleep with healthy aging.

Design, Setting, and Participants

In this cohort study using data from the Nurses' Health Study, participants aged 50 years or older and free of major chronic diseases in 1992 were prospectively followed up for 20 years. Data were analyzed from January to May 2022.

Exposures

Three measures for sedentary behaviors (hours watching television, sitting at work, and other sitting at home) and 2 measures for LPA (hours of standing or walking around at home [LPA-Home] and at work [LPA-Work]).

Main Outcomes and Measures

Healthy aging was defined as survival to at least age 70 years with maintenance of 4 health domains (ie, no major chronic diseases and no impairment in subjective memory, physical function, or mental health). The isotemporal substitution model was used to evaluate the potential impact on healthy aging of replacing 1 hour of 1 behavior with equivalent duration of another.

Results

Among 45 176 participants (mean [SD] age, 59.2 [6.0] years), 3873 (8.6%) women achieved healthy aging. After adjustment for covariates including MVPA, each increment of 2 hours per day in sitting watching television was associated with a 12% (95% CI, 7%-17%) reduction in the odds of healthy aging. In contrast, each increase of 2 hours per day in LPA-Work was associated with a 6% (95% CI, 3%-9%) increase in the odds of healthy aging. Replacing 1 hour of sitting watching television with LPA-Home (OR, 1.08; 95% CI, 1.05-1.12), LPA-Work (OR, 1.10; 95% CI, 1.07-1.14), or MVPA (OR, 1.28; 95% CI, 1.23-1.34) was associated with increased odds of healthy aging. Among participants who slept 7 hours per day or less, replacing television time with sleep was also associated with increased odds of healthy aging.

Conclusions and Relevance

In this cohort study, longer television watching time decreased odds of healthy aging, whereas LPA and MVPA increased odds of healthy aging and replacing sitting watching television with LPA or MVPA, or with sleep in those who slept 7 hours per day or less, was associated with increased odds of healthy aging, providing evidence for rearranging 24-hour behavior to promote overall health.

Healthy Lifestyle and the Likelihood of Becoming a Centenarian

Importance

Previous studies have reported that lifestyle factors were associated with life expectancy and/or mortality, but most of them studied the middle-aged or older age groups (aged ≥60 years), and few focused on people aged 80 years or older.

Objectives

To examine healthy lifestyle and the likelihood of becoming centenarians among people aged 80 years or older in China.

Design, Settings, and Participants

Using data from the Chinese Longitudinal Healthy Longevity Survey, a nationally representative and one of the largest prospective cohorts targeting people aged 80 years or older established in 1998, a community-based, prospective nested case-control study was performed. Data were analyzed from December 1, 2022, to April 15, 2024.

Exposures

A healthy lifestyle score for 100 (HLS-100, ranging from 0 to 6), including smoking, exercise, and dietary diversity, was constructed, with higher scores indicating potentially better health outcomes.

Main Outcomes and Measures

The primary outcome was survivorship to becoming a centenarian by 2018 (the end of follow-up). Information on sociodemographic characteristics, lifestyle factors, and other covariates was collected.

Results

The sample comprised 5222 individuals (61.7% women, mean [SD] age, 94.3 [3.3] years), including 1454 identified centenarians and 3768 controls (died before becoming centenarians) matched by age, sex, and year of entry. During a median follow-up of 5 (IQR, 3-7) years, 373 of 1486 individuals among the lowest HLS-100 (0-2) group and 276 of 851 individuals among the highest HLS-100 (5-6) group became centenarians. The adjusted odds ratio (AOR) comparing the highest vs the lowest HLS-100 groups was 1.61 (95% CI, 1.32-1.96; P < .001 for trend). An association was noted when we further treated centenarians with relatively healthy status as the outcome, as evaluated by self-reported chronic conditions, physical and cognitive function, and mental wellness (AOR, 1.54; 95% CI, 1.05-2.26). Similar results were observed in other sensitivity analyses.

Conclusions and Relevance

In this case-control study of Chinese older adults, adhering to a healthy lifestyle appears to be important even at late ages, suggesting that constructing strategic plans to improve lifestyle behaviors among all older adults may play a key role in promoting healthy aging and longevity.

Plant-Based Milk Consumption and Growth in Children 1-10 Years of Age

BACKGROUND

The effects of plant-based milk consumption on the growth of children are unclear.

OBJECTIVES

We aimed to evaluate the relationship between plant-based milk consumption and BMI in childhood. Secondary objectives were to examine the association with height and whether these relationships are mediated by dairy milk intake and modified by age or the type of plant-based milk consumed.

METHODS

A prospective cohort study was conducted in healthy children aged 1-10 y through the TARGet Kids! primary care research network in Toronto, Canada. Linear mixed-effect modeling and logistic generalized estimating equations were used to evaluate the association between plant-based milk consumption (number of 250 mL cups/d) and BMI. A mediation analysis was conducted to examine whether dairy milk intake mediated these relationships. Effect modification by age and type of plant-based milk was explored.

RESULTS

Among 7195 children (mean age: 3.1 y; 52.3% male), higher plant-based milk consumption was associated with lower BMI (P = 0.0002) and height (P = 0.005). No association was found with BMI categories. Lower dairy milk intake partially mediated these relationships. A child aged 5 y who consumed 3 cups of plant-based milk compared with 3 cups of dairy milk had a lower weight of 0.5 kg and lower height of 0.8 cm. Associations did not change over time and were similar for children who consumed soy milk compared with other plant-based milks.

CONCLUSIONS

Plant-based milk consumption was associated with lower BMI and height, but both were within the normal range on average. Future longitudinal studies are needed to determine whether these associations persist over time.

Dietary protein intake in midlife in relation to healthy aging - results from the prospective Nurses' Health Study cohort

BACKGROUND

Protein intake plays an important role in maintaining the health status of older adults. However, few epidemiologic studies examined midlife protein intake in relation to healthy aging.

OBJECTIVES

The objective of this study was to evaluate the long-term role of dietary protein intake in healthy aging among female participants in the prospective Nurses' Health Study (NHS) cohort.

METHODS

We included 48,762 NHS participants aged <60 y in 1984. Total protein, animal protein, dairy protein (a subset of animal protein), and plant protein were derived from validated food frequency questionnaires. Healthy aging was defined as being free from 11 major chronic diseases, having good mental health, and not having impairments in either cognitive or physical function, as assessed in the 2014 or 2016 NHS participant questionnaires. We used multivariate logistic regression adjusted for lifestyle, demographics, and health status to estimate the odds ratios (ORs) and 95% confidence intervals for protein intake in relation to healthy aging.

RESULTS

A total of 3721 (7.6%) NHS participants met our healthy aging definition. Protein intake was significantly associated with higher odds of healthy aging. The ORs (95% confidence intervals) per 3%-energy increment with healthy aging were 1.05 (1.01, 1.10) for total protein, 1.07 (1.02, 1.11) for animal protein, 1.14 (1.06, 1.23) for dairy protein, and 1.38 (1.24, 1.54) for plant protein. Plant protein was also associated with higher odds of absence of physical function limitations and good mental status. In substitution analyses, we observed significant positive associations for the isocaloric replacement of animal or dairy protein, carbohydrate, or fat with plant protein (ORs for healthy aging: 1.22-1.58 for 3% energy replacement with plant protein).

CONCLUSIONS

Dietary protein intake, especially plant protein, in midlife, is associated with higher odds of healthy aging and with several domains of positive health status in a large cohort of female nurses.

Determinants and indicators of successful aging as a multidimensional outcome: a systematic review of longitudinal studies

Background

Successful aging (SA) has been coined as a term to describe the multidimensional aspects associated with achieving optimal combination of physical and mental health along with social well-being health, mental and social well-being at older age. In recent years there has been an increased interest in understanding the role of determinants of SA, such as demographic, biological, behavioral, psychological and social factors. To synthesize the recent evidence, we conducted a systematic review of longitudinal studies on a range of determinants and indicators of SA defined as a multidimensional outcome.

Methods

A systematic search of PubMed, MEDLINE and Web of Science for finding eligible papers published between August 2016 and June 2023 was conducted following the Preferred Reporting Items for a Systematic Review and Meta-Analysis (PRISMA) guidelines. The review protocol was registered in PROSPERO International Prospective Register of Systematic Reviews (Registration number: CRD42021250200). The web-based automated screening tool-Rayyan-was used for title and abstract screening. The study quality was assessed using the Quality in Prognosis Studies (QUIPS) tool.

Results

A total of 3,191 records were initially identified using the predefined search strategy. Out of 289 articles selected for full text screening, 22 were found eligible and included in the review. A variety of factors have been explored in relation to SA, ranging from socio-demographic factors, nutrition, lifestyle, biological pathways, psychological health, and well-being. Overall, the results of recent studies have confirmed the role of metabolic health, adherence to healthy dietary patterns, such as the Mediterranean diet, physical activity, non-smoking, and higher socio-economic status as main factors associated with higher odds for SA. Emerging research highlights the role of psycho-social factors and early life health as determinants of SA.

Conclusion

In summary, this review highlights the importance of healthy living and monitoring metabolic risk along with sustaining psychological well-being in adult life as major determinants of SA. Further methodological and research work on SA would pave the way toward development of adequate health promotion policies in aging societies.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021250200, CRD42021250200.

Correlation between dietary patterns and cognitive function in older Chinese adults: A representative cross-sectional study

Objective

The objective of this study was to investigate the relationship between dietary patterns and cognitive function in older adults (≥60 years old).

Methods

Food intake was quantitatively assessed by the Food Frequency Questionnaire (FFQ), and cognitive function was assessed by the Chinese version of the Simple Mental State Examination Scale (MMSE). Four major dietary patterns were identified by the factor analysis (FA) method. The relationship between dietary patterns and cognitive function was evaluated by logistic regression.

Results

A total of 884 participants were included in the study. Four dietary patterns (vegetable and mushroom, oil and salt, seafood and alcohol, and oil tea dietary patterns) were extracted. In the total population, Model III results showed that the fourth quartile of dietary pattern factor scores for the vegetable and mushroom pattern was 0.399 and 7.056. The vegetable and mushroom dietary pattern may be a protective factor for cognitive function, with p-value = 0.033, OR (95% CI): 0.578 (0.348, 0.951) in Model III (adjusted for covariates: sex, ethnic, marital, agricultural activities, smoking, drinking, hypertension, diabetes, dyslipidemia, BMI, and dietary fiber). In the ethnic stratification analysis, the scores of dietary pattern factors of the vegetable and mushroom among the Yao participants were 0.333 and 5.064. The Vegetable and mushroom diet pattern may be a protective factor for cognitive function, p-value = 0.012, OR (95% CI): 0.415 (0.206, 0.815).

Conclusion

The fourth quartile of the vegetable and mushroom dietary pattern scores showed dose-dependent and a strong correlation with cognitive function. Currently, increasing vegetable and mushroom intake may be one of the effective ways to prevent and mitigate cognitive decline. It is recommended to increase the dietary intake of vegetables and mushroom foods.

Your height affects your health: genetic determinants and health-related outcomes in Taiwan

BACKGROUND

Height is an important anthropometric measurement and is associated with many health-related outcomes. Genome-wide association studies (GWASs) have identified hundreds of genetic loci associated with height, mainly in individuals of European ancestry.

METHODS

We performed genome-wide association analyses and replicated previously reported GWAS-determined single nucleotide polymorphisms (SNPs) in the Taiwanese Han population (Taiwan Biobank; n = 67,452). A genetic instrument composed of 251 SNPs was selected from our GWAS, based on height and replication results as the best-fit polygenic risk score (PRS), in accordance with the clumping and p-value threshold method. We also examined the association between genetically determined height (PRS₂₅₁) and measured height (phenotype). We performed observational (phenotype) and genetic PRS₂₅₁ association analyses of height and health-related outcomes.

RESULTS

GWAS identified 6843 SNPs in 89 genomic regions with genome-wide significance, including 18 novel loci. These were the most strongly associated genetic loci (EFEMP1, DIS3L2, ZBTB38, LCORL, HMGA1, CS, and GDF5) previously reported to play a role in height. There was a positive association between PRS₂₅₁ and measured height (p < 0.001). Of the 14 traits and 49 diseases analyzed, we observed significant associations of measured and genetically determined height with only eight traits (p < 0.05/[14 + 49]). Height was positively associated with body weight, waist circumference, and hip circumference but negatively associated with body mass index, waist-hip ratio, body fat, total cholesterol, and low-density lipoprotein cholesterol (p < 0.05/[14 + 49]).

CONCLUSIONS

This study contributes to the understanding of the genetic features of height and health-related outcomes in individuals of Han Chinese ancestry in Taiwan.

Rotating Night Shift Work and Healthy Aging After 24 Years of Follow-up in the Nurses' Health Study

IMPORTANCE

Rotating night shift work is associated with higher mortality. Whether it is also associated with overall health among those who survive to older ages remains unclear.

OBJECTIVE

To examine whether rotating night shift work is associated with healthy aging after 24 years of follow-up in the Nurses' Health Study, a cohort study among registered female nurses.

DESIGN, SETTING, AND PARTICIPANTS

For this cohort study, a composite healthy aging phenotype was ascertained among 46 318 participants who were aged 46 to 68 years and free of major chronic diseases in 1988 when the history of night shift work was assessed. In a secondary analysis in which cognitive function decline was considered in the healthy aging definition, 14 273 nurses were involved. Data were analyzed from March 1 to September 30, 2021.

EXPOSURES

Duration of rotating night shift work.

MAIN OUTCOMES AND MEASURES

Healthy aging was defined as reaching at least 70 years of age and being free of 11 major chronic diseases, memory impairment, physical limitation, or deteriorated mental health.

RESULTS

Of 46 318 female nurses (mean [SD] age at baseline, 55.4 [6.1] years), 3695 (8.0%) achieved healthy aging after 24 years of follow-up. After adjusting for established and potential confounders, compared with women who never worked rotating night shifts, the odds of achieving healthy aging decreased significantly with increasing duration of night shift work. The odds ratios were 0.96 (95% CI, 0.89-1.03) for 1 to 5 years, 0.92 (95% CI, 0.79-1.07) for 6 to 9 years, and 0.79 (95% CI, 0.69-0.91) for 10 or more years of night shift work (P = .001 for trend). This association did not differ substantially by age and lifestyles and was consistent for 4 individual dimensions of healthy aging. Results were similar in a secondary analysis, with an odds ratio of 0.73 (95% CI, 0.60-0.89; P < .001 for trend) comparing 10 or more years of night shift work vs no night shift work.

CONCLUSIONS AND RELEVANCE

In this cohort study, rotating night shift work was associated with decreased probability of healthy aging among US female nurses. These data support the notion that excess night shift work is a significant health concern that may also lead to deteriorated overall health among older individuals.

Do Remittances Enhance Elderly Adults' Healthy Social and Physical Functioning? A Cross-Sectional Study in Nigeria

Existing research demonstrates that the effect of remittances on different health outcomes of elderly adults in low-income countries with inadequate social security is inconclusive. The present study set out to fill this gap by examining the effects of receiving remittances on the healthy social and physical functioning of Nigeria’s elderly adults. We also investigate the nonlinear association between remittances and social and physical functioning to identify the minimum amount required to engender healthy social and physical functioning in Nigerian elderly adults. This study utilized data from the 2018/2019 Nigerian Living Standard Survey (NLSS), which included 55,350 young people aged 12–44 (control group) and 18,937 elderly adults aged 45 and above (treatment group). We addressed our objectives using logistic regression-adjusted predicted probabilities and predictive margins. The results reveal that remittance recipients have higher healthy social functioning probabilities than non-recipients. We also found that the influence that remittances have on social functioning depends on the amount of the remittances received. Quantitatively, receiving more than NGN 1,200,000 in remittances ensures increased social functioning probabilities. Given the disparity between the average remittance amount of NGN 54,306.92 received by elderly adults and the NGN 1,200,000 threshold associated with healthy social functioning, bridging this gap is paramount for promoting social functioning among Nigerian elderly adults. We also discussed policy implications for fostering the healthy aging of the population in the interim.

Factors associated with depression across age groups of older adults: The Singapore Chinese health study

OBJECTIVES

We studied sociodemographic and health factors associated with depression across three age groups of community-dwelling older adults.

METHODS/DESIGN

We used data from 16,785 participants from the third follow-up of the Singapore Chinese Health Study (mean age: 73, range: 61-96 years). We defined depression as having a score of ≥5 using the 15-item Geriatric Depression Scale. We used regression splines to examine the pattern of depression risk with age and applied multivariable logistic regression to study factors associated with depression.

RESULTS

Increasing age was associated with depression in an inverted J-shape relationship with the highest odds ratio (OR) at age 75. Compared to the youngest-old (<70 years), the middle-old (70-80 years) had higher odds of depression [OR = 1.20, 95% confidence interval (CI) = 1.09-1.31], while the oldest-old (>80 years) had no increased risk (OR = 1.01, 95% CI = 0.89-1.15). We also found demographic (men, lower education, unemployment), social (living alone, poor social support, no social activity) and health factors (instrumental limitations, poor physical function, function-limiting pain, chronic diseases, cognitive impairment, poor sleep quality, poor self-rated health) associated with depression. In stratified analysis by age groups, the OR estimates for lower education level, instrumental limitations and cognitive impairment decreased with age, whereas the risk of depression for men increased with age (all p-values for interaction<0.03).

CONCLUSIONS

Compared to the youngest-old, the likelihood of depression was highest among middle-old adults and decreased to null in the oldest-old. The associations between some factors and depression were attenuated with age, suggesting a coping mechanism among oldest-old survivors.

Association Between Combined Lifestyle Factors and Healthy Ageing in Chinese Adults: The Singapore Chinese Health Study

BACKGROUND

The aim of the study was to examine the relations of individual lifestyle factors and its composite score with healthy ageing among Chinese adults.

METHOD

We included 14 159 participants aged 45-74 years at baseline from the Singapore Chinese Health Study, a population-based prospective cohort. A protective lifestyle score (0-5 scale) was calculated at baseline (1993-1998) and updated at the second follow-up visit (2006-2010) on the basis of optimal body mass index (18.5-22.9 kg/m2), healthy diet (upper 40% of the Alternative Healthy Eating Index score), being physically active (≥2 h/wk of moderate activity or ≥0.5 h/wk of strenuous activity), nonsmoking (never smoking), and low-to-moderate alcohol drinking (>0 to ≤14 drinks/wk for men and >0 to ≤7 drinks/wk for women). Healthy ageing was assessed at the third follow-up visit (2014-2016) and was defined as absence of specific chronic diseases, absence of cognitive impairment and limitations in instrumental activities of daily living, good mental and overall self-perceived health, good physical functioning, and no function-limiting pain.

RESULTS

About 20.0% (2834) of the participants met the criteria of healthy ageing after a median follow-up of 20 years. Each 1-point increase in the protective lifestyle score computed at baseline and second follow-up visits was associated with higher likelihood of healthy ageing by 25% (95% CI: 20%-30%) and 24% (18%-29%), respectively. The population-attributable risk percent of adherence to 4-5 protective lifestyle factors was 34.3% (95% CI: 25.3%-42.3%) at baseline and 31.3% (23.0%-38.7%) at second follow-up visits for healthy ageing. In addition, positive increase in lifestyle scores from baseline to second follow-up visits was also significantly associated with a higher likelihood of healthy ageing with an odds ratio of 1.18 (95% CI: 1.12%-1.24%) for each increment in protective lifestyle score.

CONCLUSIONS

Our findings confirmed that adopting healthy lifestyle factors, even after midlife, was associated with healthy ageing at old age.

Sleep Duration and Snoring at Midlife in Relation to Healthy Aging in Women 70 Years of Age or Older

PURPOSE

Both short and long sleep durations are associated with higher mortality. This study examined the association between sleep duration and overall health among those who survive to older ages.

PARTICIPANTS AND METHODS

In the Nurses' Health Study, participants without major chronic diseases in 1986 and survived to age 70 years or older in 1995-2001 were included. Habitual sleep duration and snoring were self-reported in 1986. Healthy aging was defined as being free of 11 major chronic diseases and having no cognitive impairment, physical impairment, or mental health limitations. Logistic regression was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for healthy aging.

RESULTS

Of the 12,304 participants, 1354 (11.0%) achieved healthy aging. We observed a non-linear association between sleep duration and the odds of achieving healthy aging. Compared with women sleeping 7 hours per day, women with longer sleep duration were less likely to achieve healthy aging; there was also a suggestion of lower odds of healthy aging for shorter sleepers, although the associations did not reach statistical significance: the multivariate-adjusted ORs (95% CIs) of healthy aging for those sleeping ≤5, 6, 8, and ≥9 hours were 0.94 (0.70, 1.27), 0.88 (0.76, 1.02), 0.83 (0.72, 0.96), and 0.60 (0.43, 0.84), respectively. Similar non-linear associations were consistently observed for individual dimensions of healthy aging. Regular snoring was associated with 31% lower odds of healthy aging (95% CI: 0.54, 0.88), which was primarily due to lower odds of having no major chronic diseases.

CONCLUSION

Both short and long sleep durations as well as regular snoring at midlife were associated with lower odds of healthy aging in later life.

Proposal of Nursing Diagnosis "Readiness for Enhanced Healthy Aging": A Concept Analysis

PURPOSE

To analyze the concept of healthy aging and propose the development of a nursing diagnosis METHODS: Concept analysis using the method proposed by Walker and Avant FINDINGS: Four bibliographic databases were searched, and 36 articles were included in the analysis. Seven antecedents, seven attributes, and three consequences for "healthy aging" were identified.

CONCLUSIONS

The concept analysis supported the development of the new nursing diagnosis "readiness for enhanced healthy aging," which can assist nurses in implementing actions aimed at promoting the health of older adults.

IMPLICATION FOR NURSING PRACTICE

The establishment of a nursing diagnosis may provide nurses the opportunity to implement interventions that promote the maintenance of functional and cognitive capacity, psychological and spiritual well-being, and social engagement, aiming at healthy aging with high quality of life.

Consumption of Nuts at Midlife and Healthy Aging in Women

Background

Nut consumption may reduce age-related diseases and lead to better health and well-being in aging. Many conditions of aging develop over decades, and thus earlier lifestyle factors may particularly influence later health.

Methods

In 1998 and 2002, we administered food frequency questionnaires to assess nut consumption (peanuts, walnuts, and other nuts and peanut butter) in women in the Nurses' Health Study in their 50 s/early 60 s. In 2012, those who survived beyond 65 years with no chronic diseases, no reported memory impairment, no physical disabilities, and intact mental health were considered "healthy agers." We used multivariable logistic regression to estimate odds ratios for healthy versus usual aging, controlled for sociodemographic, behavioral, dietary, and other potential confounding factors.

Results

Of 33,931 participants at midlife, 16% became "healthy agers." After age adjustment, we observed a significant association between total nut consumption at midlife and higher odds of healthy aging, with strongest associations observed excluding peanut butter (odds ratio (OR) = 1.46, 95% confidence interval (CI) 1.32-1.62, ≥3 servings/week versus none). Findings were attenuated after further control for covariates, including overall diet quality (OR = 1.14, 95% CI 1.02-1.28, P trend = 0.05). For nut types, we found statistically significantly higher odds of healthy aging across peanuts, walnuts, and other nuts after age adjustment. After full control for confounders, only walnut consumption remained associated with healthy aging (P trend = 0.0001); for example, the OR was 1.20 (95% CI 1.00-1.44) for ≥2 servings/week versus none.

Conclusions

Women consuming nuts at midlife have a greater likelihood of overall health and well-being at older ages. Nut consumption may represent a simple intervention to explore and promote healthy aging.

Tryptophan metabolism is differently regulated between large and small dogs

Companion dogs have recently been promoted as an animal model for the study of aging due to their similar disease profile to humans, the sophistication of health assessment and disease diagnosis, and the shared environments with their owners. In addition, dogs show an interesting life history trait pattern where smaller individuals are up to two-fold longer lived than their larger counterparts. While some of the mechanisms underlying this size and longevity trade-off are strongly suspected (i.e., growth hormone/IGF-I), there are likely a number of undiscovered mechanisms as well. Accordingly, we have completed a large-scale global metabolomic profiling of dogs encompassing a range of sizes and ages from three cities across the USA. We found a surprisingly strong location signal in the metabolome, stronger in fact than any signal related to age, breed, or sex. However, after controlling for the effects of location, tryptophan metabolism emerged as significantly associated with weight of the dogs, with small dogs having significantly higher levels of tryptophan pathway metabolites. Overall, our results point toward novel, testable hypotheses about the underlying physiological mechanisms that influence size and longevity in the companion dog and suggest that dogs may be useful in sorting out the complexities of the tryptophan metabolic network.

Cognitive Function and Consumption of Fruit and Vegetable Polyphenols in a Young Population: Is There a Relationship?

Scientific evidence has shown the relationship between consumption of fruits and vegetables and their polyphenols with the prevention or treatment of diseases. The aim of this review was to find out whether the same relationship exists between fruits and vegetables and cognitive function, especially memory, in a young population. The mechanisms by which polyphenols of fruits and vegetables can exert cognitive benefits were also evaluated. These compounds act to improve neuronal plasticity through the protein CREB (Camp Response Element Binding) in the hippocampus, modulating pathways of signaling and transcription factors (ERK/Akt). In the same way, brain-derived neurotrophic factor (BDNF) is implicated in the maintenance, survival, growth, and differentiation of neurons. All these effects are produced by an increase of cerebral blood flow and an increase of the blood’s nitric oxide levels and oxygenation.

Advances in Understanding the Molecular Basis of the Mediterranean Diet Effect

Increasingly, studies showing the protective effects of the Mediterranean diet (MedDiet) on different diseases (cardiovascular, diabetes, some cancers, and even total mortality and aging indicators) are being published. The scientific evidence level for each outcome is variable, and new studies are needed to better understand the molecular mechanisms whereby the MedDiet may exercise its effects. Here, we present recent advances in understanding the molecular basis of MedDiet effects, mainly focusing on cardiovascular diseases but also discussing other related diseases. There is heterogeneity in defining the MedDiet, and it can, owing to its complexity, be considered as an exposome with thousands of nutrients and phytochemicals. We review MedDiet composition and assessment as well as the latest advances in the genomic, epigenomic (DNA methylation, histone modifications, microRNAs, and other emerging regulators), transcriptomic (selected genes and whole transcriptome), and metabolomic and metagenomic aspects of the MedDiet effects (as a whole and for its most typical food components). We also present a critical review of the limitations of the studies undertaken and propose new analyses and greater bioinformatic integration to better understand the most important molecular mechanisms whereby the MedDiet as a whole, or its main food components, may exercise their protective effects.