Association of zinc intake with risk of impaired physical function and frailty among older adults

Associations of nutritional intake and inflammatory factors with sarcopenia in community-dwelling older adults: a cross-sectional study

PURPOSE

Sarcopenia is an age-related disease that is related to nutritional intake and chronic low-grade inflammation. The aim of this study was to investigate the association of dietary intake, inflammatory markers and sarcopenia among the community-dwelling older adults.

METHODS

A total of 1001 older adults aged 60 and above were recruited. According to the criteria established by the Asian Working Group for Sarcopenia 2019, this paper assessed the presence of sarcopenia and using a Food Frequency Questionnaire to evaluate daily dietary intake. Serum levels of inflammatory markers were measured using the ELISA method.

RESULTS

A total of 1001 participants took part in the study (mean 70.6 years), comprising 396 males and 605 females, the prevalence of sarcopenia was 19.6%. Multivariate analysis revealed that high levels of leucine, methionine, threonine, histidine, aspartic acid, calcium, zinc, and vitamin C were associated with a lower risk of sarcopenia. Higher dietary inflammatory index scores were associated with a higher risk of sarcopenia (OR  1.67, 95% CI 1.12-2.47). Higher tumor necrosis factor-like weak inducer of apoptosis (TWEAK) (OR 1.04, 95% CI 1.02-1.07) was associated with a higher risk of sarcopenia, and a lower skeletal muscle mass, strength, and physical function. Conversely, higher insulin-like growth factor-1 (IGF-1) (OR 0.83, 95% CI 0.74-0.94) and glutathione S-transferase (GST) (OR 0.75, 95% CI 0.61-0.91) were associated with a lower risk of sarcopenia.

CONCLUSIONS

This cross-sectional study revealed alterations in amino acid and micronutrient intake among older adults with sarcopenia. The levels of TWEAK were associated with an increased risk of sarcopenia, whereas IGF-1 and GST were associated with a reduced risk of sarcopenia.

The role of composite dietary antioxidants in elderly cognitive function: insights from NHANES

Objective

This study investigates the relationship between the Composite Dietary Antioxidant Index (CDAI) and cognitive function among elderly individuals, aiming to understand how increased antioxidant intake affects cognitive abilities in an aging population.

Methods

Utilizing data from the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2014, we analyzed a sample of 2,516 participants aged 60 and above. Cognitive performance was assessed using the CERAD Word Learning and Recall Test, the Animal Fluency Test, and the Digit Symbol Substitution Test. Multivariable regression models were adjusted for demographic, dietary, and health-related factors to explore the association between CDAI scores and cognitive outcomes.

Results

The regression analyses showed a statistically significant positive association between higher CDAI scores and cognitive performance across several tests. Specifically, increments in CDAI were associated with increased scores in the CERAD Word Learning Test: Score 1 (β = 0.04, 95% CI [0.03, 0.06]), Score 2 (β = 0.04, 95% CI [0.02, 0.05]), Score 3 (β = 0.04, 95% CI [0.02, 0.06]), and the Delayed Recall Test (β = 0.04, 95% CI [0.01, 0.06]). Additionally, significant improvements were observed in the Animal Fluency Test (β = 0.19, 95% CI [0.14, 0.24]) and the Digit Symbol Test (β = 0.55, 95% CI [0.39, 0.71]). Subgroup analyses further highlighted that higher CDAI scores conferred more pronounced cognitive benefits in women, individuals aged 80 and above, Non-Hispanic Black people, and those with lower educational levels, suggesting that dietary antioxidants might be particularly beneficial in these groups.

Conclusion

An antioxidant-rich diet may represent a viable intervention to mitigate age-related cognitive decline, supporting cognitive health in the elderly. These results underscore the potential public health implications of dietary recommendations aimed at increasing antioxidant consumption among older adults. Further studies are necessary to confirm these findings and to investigate the underlying mechanisms in detail.

The inverse associations between composite-dietary-antioxidant-index and sarcopenia risk in US adults

BACKGROUND

It remains unknown whether composite-dietary-antioxidant-index (CDAI) is associated with the risk of sarcopenia. This study investigated the association of CDAI with sarcopenia risk among general US adults.

METHODS

A total of 10,093 participants were enrolled in the National Health and Nutrition Examination Surveys (NHANES) from 6 survey cycles (2003-2004, 2005-2006, 2011-2012, 2013-2014, 2015-2016 and 2017-2018). Multivariate logistic regression was carried out to examine the relationship between CDAI and the risk of sarcopenia. Restricted cubic spline (RCS) curves were employed to analyze nonlinear relationships.

RESULTS

In a multi-variable logistic regression model adjusting for demographics, lifestyle, economic status and other dietary factors, higher CDAI score was related to a lower risk of sarcopenia among US adults. Compared the highest quartile of CDAI score with the lowest, the OR and 95%CI were 0.49 (0.31-0.75). Furthermore, the RCS demonstrated a linear dose-response relationship between CDAI and sarcopenia (P non-linearity=0.92). These results remained consistent across subgroups stratified by age, sex, physical activity, drinking status, body mass index (BMI), smoking habits, energy intake, and Healthy Eating Index (HEI) score. In addition, the favorable associations of CDAI were primarily attributed to Vitamin E intake.

CONCLUSION

A higher CDAI score was associated with a lower risk of sarcopenia. According to these results, a greater adherence to CDAI may benefit sarcopenia prevention in adults.

The role of zinc on nutritional status, sarcopenia, and frailty in older adults: a scoping review

BACKGROUND

Zinc (Zn) deficiency, malnutrition, sarcopenia, and frailty are prevalent among older adults and are prominent factors contributing to disability and mortality.

OBJECTIVE

This scoping review was conducted to aid understanding of the extent and types of research addressing the role of Zn in nutritional status, sarcopenia, and frailty, among older individuals.

METHOD

A systematic search was performed in August 2022 of 3 electronic databases (PubMed, Web of Science, and ProQuest) using predefined search terms. The review was conducted referring to the Arksey and O'Malley framework and PRISMA-ScR.

RESULTS

The search retrieved 16 018 records, and a total of 49 studies were included in this review after the screening. Of those, 30 were based on dietary Zn intake, 18 on tissue Zn levels, and 1 on both. Most studies were based on cross-sectional data from community-dwelling older adults. Studies addressing the associations between Zn status and individual anthropometric and sarcopenia-related variables reported inconsistent results. However, most studies reported inverse associations between malnutrition, frailty, and Zn status.

CONCLUSION

There was more consistent evidence of the relationship of Zn status with malnutrition, sarcopenia, and frailty rather than with individual nutritional parameters. Validated screening and assessment tools and criteria and prospective studies are required to elucidate the relationship of Zn with sarcopenia and frailty in the older population.

Association between diet quality and malnutrition: pooled results from two population-based studies in older adults

BACKGROUND

The role of diet quality on malnutrition in older adults is uncertain, due the paucity of the research conducted and the use of use of screening tools that did not consider phenotypic criteria of malnutrition.

OBJECTIVE

To evaluate the association of two indices of diet quality, namely the Mediterranean Diet Adherence Screener (MEDAS) and the Alternative Healthy Eating Index (AHEI-2010), with malnutrition among community-dwelling older adults in Spain.

METHODS

Cross-sectional analysis of data from 1921 adults aged ≥ 60 years from the Seniors-ENRICA-1 (SE-1) study, and 2652 adults aged ≥ 65 years from the Seniors-ENRICA-2 (SE-2) study. Habitual food consumption was assessed through a validated diet history. Malnutrition was defined according to the Global Leadership Initiative on Malnutrition (GLIM) phenotypic criteria. Statistical analyses were performed with logistic regression with adjustment for socioeconomic and lifestyle variables as well as for total energy and protein intake.

RESULTS

The prevalence of malnutrition in the SE-1 study was 9.5% (95% confidence interval: 8.2 to 10.9) and 11.7% (10.5 to 13.9) in the SE-2. Adherence to the MEDAS score was associated with lower prevalence of malnutrition [pooled odds ratio for high (≥ 9 points) vs. low adherence (< 7 points): 0.64 (0.48-0.84); p-trend < 0.001]. Higher adherence to the AHEI-2010 also showed an inverse association with malnutrition (pooled odds ratio for quartile 4 vs. 1: 0.65 (0.49-0.86); p-trend 0.006). Among the individual components, higher consumption of fish and long-chain n-3 fatty acids in MEDAS and AHEI-2010, and of vegetables and nuts and legumes in AHEI-2010, and lower intake of trans-fat and sugar-sweetened beverages and fruit juice in AHEI-2010 were independently associated with lower odds of malnutrition.

CONCLUSION

Adherence to high diet-quality patterns was associated with lower frequency of malnutrition among older adults.

CLINICAL TRIAL REGISTRY

ClinicalTrials.gov identifier: NCT02804672. June 17, 2016.; ClinicalTrials.gov NCT03541135. May 30, 2018.

Dietary inflammatory index, dietary total antioxidant capacity, and frailty among older Chinese adults

OBJECTIVES

Frailty is an age-related syndrome associated with poor health outcomes. Studies in developed countries indicate that the dietary inflammatory index (DII) and dietary total antioxidant capacity (DTAC) are important dietary factors influencing the risk of frailty in older adults. However, few studies have explored the association between DII, DTAC, and frailty among older Chinese adults. The objective of the current study was to examine whether DII and DTAC were associated with pre-frailty or frailty among older Chinese adults.

DESIGN

A cross-sectional study.

SETTING

Community-based.

PARTICIPANTS

We included 6414 participants aged ≥60 years.

MEASUREMENTS

Dietary intake was assessed using a validated food frequency questionnaire (FFQ). The DII and energy-adjusted DII (E-DII) were calculated using food parameters. DTAC was estimated using two widely adopted antioxidant scores: DTAC based on ferric reducing antioxidant power and dietary antioxidant quality score (DAQS) obtained from vitamins (vitamins A, C, and E) and minerals (zinc and selenium) with antioxidant functions. Frailty was assessed using the frailty index (FI) calculated from 28 health-related deficits. Individuals were classified as robust (FI ≤ 0.10), pre-frailty (FI > 0.10 to <0.25), or frailty (FI ≥ 0.25). Multiple logistic regression models were used to evaluate the associations of DII and DTAC with pre-frailty and frailty.

RESULTS

After adjusting for confounding factors, individuals in the highest DII quintile (Q5) were more likely to have pre-frailty (odds ratio [OR] = 1.56; 95% confidence interval [CI]: 1.25-1.93; P for trend <0.001) than those in the lowest Q1. A similar positive association was detected for E-DII and pre-frailty. A significant association was found between DII and frailty. Compared with the lowest Q1, the highest Q5 of DTAC was negatively correlated with pre-frailty (OR = 0.66; 95% CI: 0.52-0.84; P for trend <0.001) and frailty (OR = 0.71; 95% CI: 0.50-0.1.03; P for trend <0.001). The DAQS yielded results similar to pre-frailty results (OR = 0.72; 95% CI: 0.58-0.89; P < 0.001). There was no evidence suggesting an association between DAQS and frailty.

CONCLUSIONS

More proinflammatory diets were linked to higher pre-frailty risk, whereas higher levels of dietary antioxidants were associated with lower pre-frailty and frailty risk among older Chinese adults.

Improving Cognitive Function with Nutritional Supplements in Aging: A Comprehensive Narrative Review of Clinical Studies Investigating the Effects of Vitamins, Minerals, Antioxidants, and Other Dietary Supplements

Cognitive impairment and dementia are burgeoning public health concerns, especially given the increasing longevity of the global population. These conditions not only affect the quality of life of individuals and their families, but also pose significant economic burdens on healthcare systems. In this context, our comprehensive narrative review critically examines the role of nutritional supplements in mitigating cognitive decline. Amidst growing interest in non-pharmacological interventions for cognitive enhancement, this review delves into the efficacy of vitamins, minerals, antioxidants, and other dietary supplements. Through a systematic evaluation of randomized controlled trials, observational studies, and meta-analysis, this review focuses on outcomes such as memory enhancement, attention improvement, executive function support, and neuroprotection. The findings suggest a complex interplay between nutritional supplementation and cognitive health, with some supplements showing promising results and others displaying limited or context-dependent effectiveness. The review highlights the importance of dosage, bioavailability, and individual differences in response to supplementation. Additionally, it addresses safety concerns and potential interactions with conventional treatments. By providing a clear overview of current scientific knowledge, this review aims to guide healthcare professionals and researchers in making informed decisions about the use of nutritional supplements for cognitive health.

The role of nutrition in the prevention of sarcopenia

Sarcopenia is a common skeletal muscle disorder characterized by a loss of muscle mass and impaired muscle function that is associated with poor health outcomes. Although nutrition is considered an important factor in the etiology of sarcopenia, the preventive potential of diet, specifically the extent to which differences in habitual patterns of diet and/or nutrient intakes impact risk of its development, is poorly understood. This narrative review considered research evidence on dietary patterns and nutrient intakes in mid- (<60 y) and young-older (60-70 y) adulthood to evaluate how they relate to age-related changes in muscle mass and function. A key finding was that current evidence on adult diet and sarcopenia risk in older age is limited and fragmented, with different outcomes reported across studies (for example, lean mass, strength) and few reporting links to incident diagnosed sarcopenia. As these outcomes are not interchangeable, it challenges collation of the evidence, leaving many gaps in understanding. There is also limited information about adult (<70 y) diet and few longitudinal studies with repeated dietary assessments to enable definition of cumulative exposures across adulthood. However, despite these limitations, findings from studies of dietary patterns already provide reasonably consistent messages about the benefits of diets of higher quality in earlier adulthood for later physical performance, although whole-diet intervention trials are urgently needed to understand their potential. In comparison, there is little evidence of benefits of higher intakes of individual nutrients in earlier adulthood for later muscle mass and function. Although these gaps need to be addressed in future research, there may already be sufficient data to promote messages about diet quality more widely - that healthier diets of higher quality across adulthood, with known benefits for a range of health outcomes, are also linked to the effective preservation of muscle mass and function.

Effects of Daily Zinc Alone or in Combination with Other Nutrient Supplements on the Risk of Malaria Parasitaemia: A Systematic Review and Meta-Analysis of Randomised Controlled Trials

Zinc supplementation has been explored as a potential intervention to reduce the risk of malaria parasitaemia in randomised controlled trials (RCTs). However, inconsistent evidence has been obtained regarding the efficacy of zinc supplementation in the context of malaria prevention. This systematic review was implemented to survey the existing literature to determine the effects of the daily oral administration of zinc, either alone or in combination with other nutrient supplements, on the risk of malaria parasitaemia. The systematic review was prospectively registered in the PROSPERO database CRD42023424345 and followed PRISMA protocols. A comprehensive search was conducted across multiple databases, including Embase, MEDLINE, Ovid, PubMed, Scopus, ProQuest, and Google Scholar, from their inception until 6 May 2023. The risk of bias in RCTs was assessed using the Cochrane Risk of Bias Tool 2 (RoB 2). The effect sizes, represented as risk ratios (RRs) with 95% confidence intervals (CIs), were standardised by transforming them into log RRs and then pooling them using a fixed-effects or random-effects model depending on the heterogeneity across studies. Comparisons were made between individuals who received zinc alone or zinc in combination with other micronutrient supplements and those who did not receive zinc. A total of 1339 articles were identified through the database searches, and after the screening and selection process, 10 studies were included in the final synthesis. The meta-analysis revealed that zinc supplementation alone did not significantly affect the risk of malaria parasitaemia compared with placebo (p = 0.30, log RR = 0.05, 95% CI: -0.05-0.15, I² = 0.00%, with 566 malaria cases in the zinc intake group and 521 malaria cases in the placebo group). However, the analysis demonstrated a borderline significant effect of zinc supplementation in combination with other micronutrients on the risk of malaria parasitaemia compared with placebo (p = 0.05, log RR = 1.31, 95% CI: 0.03-2.59, I² = 99.22%, with 8904 malaria cases in the zinc intake group and 522 malaria cases in the placebo group). The findings of this systematic review indicate that zinc supplementation, either alone or combined with the supplementation of other micronutrients such as vitamin A, iron, or multiple nutrients, does not significantly alter the risk of malaria parasitaemia. Further research with larger sample sizes is warranted to explore the potential effects of multi-nutrient supplementation and to identify more specific micronutrients and additional factors associated with the risk of malaria, rather than just zinc alone, among individuals in different malaria-endemic areas.

Minerals and Sarcopenia in Older Adults: An Updated Systematic Review

OBJECTIVE

This systematic review aims to reevaluate the role of minerals on muscle mass, muscle strength, physical performance, and the prevalence of sarcopenia in community-dwelling and institutionalized older adults.

DESIGN

Systematic review.

SETTING AND PARTICIPANTS

In March 2022, a systematic search was performed in PubMed, Scopus, and Web of Sciences using predefined search terms. Original studies on dietary mineral intake or mineral serum blood concentrations on muscle mass, muscle strength, and physical performance or the prevalence of sarcopenia in older adults (average age ≥65 years) were included.

METHODS

Eligibility screening and data extraction was performed by 2 independent reviewers. Quality assessment was performed with the Effective Public Health Practice Project (EPHPP) Quality Assessment Tool for Quantitative Studies. Risk of bias was evaluated using the Risk Of Bias In Non-randomized Studies-of Exposure (ROBINS-E) tool.

RESULTS

From the 15,622 identified articles, a total of 45 studies were included in the review, mainly being cross-sectional and observational studies. Moderate quality of evidence showed that selenium (n = 8) and magnesium (n = 7) were significantly associated with muscle mass, strength, and physical performance as well as the prevalence of sarcopenia. For calcium and zinc, no association could be found. For potassium, iron, sodium, and phosphorus, the association with sarcopenic outcomes remains unclear as not enough studies could be included or were nonconclusive (low quality of evidence).

CONCLUSIONS AND IMPLICATIONS

This systematic review shows a potential role for selenium and magnesium on the prevention and treatment of sarcopenia in older adults. More randomized controlled trials are warranted to determine the impact of minerals on sarcopenia in older adults.

Adherence to the Mediterranean diet and risk of frailty and pre-frailty in elderly adults: A systematic review and dose-response meta-analysis with GRADE assessment

BACKGROUND

Several studies have explored the association between Mediterranean diet and frailty, but reported inconsistent results. This systematic review and dose-response meta-analysis summarized the existing evidence on the relationship between Mediterranean diet and risk of frailty and pre-frailty in elderly adults.

METHODS

A systematic search on MEDLINE (PubMed), Scopus, Institute for Scientific Information (ISI) Web of Science and Google Scholar was conducted up to January 2023. Study selection and data extraction were performed by two reviewers working in parallel. Epidemiologic studies reporting relative risks (RRs) or odds ratios (ORs) with 95% confidence intervals (CIs) for frailty/pre-frailty in relation to Mediterranean diet (as a priori dietary pattern) were considered. The overall effect size was determined using a random effects model. The body of evidence was assessed by the GRADE approach.

RESULTS

A total of 19 studies (12 cohorts and 7 cross-sectionals) were included. In cohort studies (89,608 participants/ 12,866 cases), the highest versus lowest category of Mediterranean diet was inversely associated with frailty (RR: 0.66; 95%CI: 0.55, 0.78; I²:52.4%, P_Q-test=0.02). This association was also significant in cross-sectional studies with 1093 cases among 13,581 participants (OR: 0.44; 95%CI: 0.28, 0.70; I²:81.8%, P_Q-test<0.001). Moreover, each 2-point increase in Mediterranean diet score was related to decreased risk of frailty in cohort (RR: 0.86; 95%CI: 0.80, 0.93) and cross-sectional (OR: 0.79; 95%CI: 0.65, 0.95) studies. Nonlinear association showed a decreasing slope in curve, sharper at high scores for cohort studies and a steadily reduction for cross-sectional studies. The certainty of the evidence was graded as high in both cohort and cross-sectional studies. Combining 4 effect sizes of 4 studies (12,745 participants/ 4363 cases), the highest adherence to Mediterranean diet was linked to a lower risk of pre-frailty, as well (pooled OR: 0.73; 95%CI: 0.61, 0.86; I²:40.9%, P_Q-test=0.17).

CONCLUSION

Adherence to Mediterranean diet is inversely associated with risk of frailty and pre-frailty in older adults and thus, has a considerable impact on health of this population.

Leucine Intake and Risk of Impaired Physical Function and Frailty in Older Adults

BACKGROUND

Leucine is suggested to play a central role in age-related physical decline, but the effect of dietary leucine intake on physical functioning is uncertain. We examined the prospective association between dietary leucine intake and impaired lower-extremity function (ILEF) and frailty in older adults.

METHODS

We used data from 2 956 adults aged ≥60 and older from the Seniors-ENRICA cohort. At baseline (2008-2010) and in 2012, dietary information was obtained with a validated computerized face-to-face diet history, from which energy-adjusted cumulative leucine intake per body weight was calculated. Participants were followed up through 2017 to assess incident ILEF, ascertained with the Short Physical Performance Battery, and incident frailty, according to the Fried phenotype criteria. Statistical analysis was performed with Cox models adjusted for the main potential confounders.

RESULTS

During follow-up, we identified 515 incident cases of ILEF and 241 of frailty. Compared with participants in the lowest tertile of leucine intake (35.5-89.0 mg/kg/d), those in the highest tertile (107.4-372.5 mg/kg/d) had a lower risk of ILEF (fully adjusted hazard ratio [95% confidence interval]: 0.70 [0.53-0.93], p trend: .01) and of frailty (0.63 [0.41-0.96], p trend: .03]. A higher consumption of important sources of leucine in this population, including unprocessed beef, oily and white fish, and bread, were also associated with a lower risk of incident ILEF and frailty.

CONCLUSIONS

Higher leucine intake was associated with reduced risk of ILEF and frailty. Dietary leucine, obtained from foods rich in high-quality protein, could be a key nutrient to prevent age-related physical function decline in older adults.

The Association between Dietary Protein Diversity and Protein Patterns with Frailty in Older Chinese Adults: A Population-Based Cohort Study

OBJECTIVES

Frailty is a pervasive condition among older people worldwide. Despite the association between higher protein intake and lower frailty risk has been well documented, older individuals encounter barriers to enhancing their protein consumption due to reduced appetite and impaired digestive capacity. This study aims to delve into the potential correlation between dietary protein diversity, protein patterns, and the risk of frailty among older Chinese individuals.

DESIGN

Prospective cohort study.

SETTING

Community-based.

PARTICIPANTS

2,216 participants aged 65 and above and not frail at the baseline were recruited from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) dataset spanning from 2014 to 2018.

MEASUREMENTS

Dietary protein diversity was evaluated utilizing a protein diversity score (PDS), calculated based on the results of a food frequency questionnaire. Dietary protein patterns were identified by employing principal component analysis (PCA). Frailty was ascertained using a 40-item frailty index (FI) where FI > 0.21 indicated frailty. Logistic analysis was employed to investigate the association between dietary variables and frailty.

RESULTS

541 participants were identified as frail after a 4-year follow-up. After adjusting for confounders, each 1-unit increase in PDS was linked to a 10% decrease in frailty risk. Compared to individuals with PDS ≤ 1, those with PDS scores of 2-3, 4-5, and 6 had lower risks of frailty, with OR (95% CI) of 0.78 (0.58-1.06), 0.58 (0.38-0.87), 0.42 (0.20-0.81), respectively (P trend = 0.038). Individuals who consistently maintained high PDS demonstrated a lower frailty risk in contrast to those who maintained low PDS (OR = 0.60, 95% CI, 0.41-0.87). Additionally, the "meat-fish" pattern exhibited a protective association with frailty, with OR Q4 versus Q1 (95% CI) of 0.54 (0.40-0.74), P trend < 0.001.

CONCLUSION

Maintaining a variety of dietary protein sources and following a "meat-fish" protein pattern might decrease the likelihood of frailty among the older Chinese population.