Considering the benefits of egg consumption for older people at risk of sarcopenia

Nutrition of aging people with diabetes mellitus: Focus on sarcopenia

As populations age, chronic diseases accumulate, and new health conditions emerge. One noteworthy pair that warrants further evaluation is diabetes mellitus and sarcopenia, given that the latter occurs in 28 % of the population aged over 50 who have diabetes mellitus. The management of both entails nutritional interventions, making the development of unified dietary recommendations an alluring strategy. This review aims to elucidate the current recommendations for the combined management of sarcopenia and diabetes, while featuring elements that require further research. The goal of nutritional management is to improve muscle mass and strength while regulating metabolic risk and glucose levels. To ensure muscle synthesis in the elderly, recommendations align at daily calorie intake that exceeds 30 kcal/kg, with adjustments based on comorbidities. Additionally, a protein intake of at least 1-1.2 g/kg/d is essential, emphasizing both daily and per-meal intake, and can be achieved through diet or branched-amino-acids supplements. Specific considerations for diabetes include restricted protein intake in diabetic nephropathy and exploring the potential link between branched amino acids and insulin resistance. Further recommendations that both promote metabolic health and have demonstrated at least a potential to increase muscle strength include prioritizing polyunsaturated fatty acids as a fat source and maintaining adequate levels of vitamin D. Clinicians should consult their patients on dietary optimization, but evidence is insufficient to recommend additional supplementation. Lastly, an emerging challenge of diabetes and sarcopenia is sarcopenic obesity, which requires the combination of a hypocaloric diet with increased protein intake.

Dietary protein and amino acid intakes for mitigating sarcopenia in humans

Adult humans generally experience a 0.5-1%/year loss in whole-body skeletal muscle mass and a reduction of muscle strength by 1.5-5%/year beginning at the age of 50 years. This results in sarcopenia (aging-related progressive losses of skeletal muscle mass and strength) that affects 10-16% of adults aged ≥ 60 years worldwide. Concentrations of some amino acids (AAs) such as branched-chain AAs, arginine, glutamine, glycine, and serine are reduced in the plasma of older than young adults likely due to insufficient protein intake, reduced protein digestibility, and increased AA catabolism by the portal-drained viscera. Acute, short-term, or long-term administration of some of these AAs or a mixture of proteinogenic AAs can enhance blood flow to skeletal muscle, activate the mechanistic target of rapamycin cell signaling pathway for the initiation of muscle protein synthesis, and modulate the metabolic activity of the muscle. In addition, some AA metabolites such as taurine, β-alanine, carnosine, and creatine have similar physiological effects on improving muscle mass and function in older adults. Long-term adequate intakes of protein and the AA metabolites can aid in mitigating sarcopenia in elderly adults. Appropriate combinations of animal- and plant-sourced foods are most desirable to maintain proper dietary AA balance.

Quality of plant-based diets and frailty incidence: a prospective analysis of UK biobank participants

BACKGROUND

Substantial evidence supports the inverse association between adherence to healthy dietary patterns and frailty risk. However, the role of plant-based diets, particularly their quality, is poorly known.

OBJECTIVE

To examine the association of two plant-based diets with incidence of physical frailty in middle-aged and older adults.

DESIGN

Prospective cohort.

SETTING

United Kingdom.

SUBJECTS

24,996 individuals aged 40-70 years, followed from 2009-12 to 2019-22.

METHODS

Based on at least two 24-h diet assessments, we built two diet indices: (i) the healthful Plant-based Diet Index (hPDI) and (ii) the unhealthful Plant-based Diet Index (uPDI). Incident frailty was defined as developing ≥3 out of 5 of the Fried criteria. We used Cox models to estimate relative risks (RR), and their 95% confidence interval (CI), of incident frailty adjusted for the main potential confounders.

RESULTS

After a median follow-up of 6.72 years, 428 cases of frailty were ascertained. The RR (95% CI) of frailty was 0.62 (0.48-0.80) for the highest versus lowest tertile of the hPDI and 1.61 (1.26-2.05) for the uPDI. The consumption of healthy plant foods was associated with lower frailty risk (RR per serving 0.93 (0.90-0.96)). The hPDI was directly, and the uPDI inversely, associated with higher risk of low physical activity, slow walking speed and weak hand grip, and the uPDI with higher risk of exhaustion.

CONCLUSIONS

In British middle-age and older adults, greater adherence to the hPDI was associated with lower risk of frailty, whereas greater adherence to the uPDI was associated with higher risk.

Microalgae: potential novel protein for sustainable human nutrition

To support a global population of ~10 billion people in 2050, dietary protein demand is forecast to increase 32-78% compared to 2017, requiring significantly higher planetary resources. Microalgae are an attractive sustainable protein source compared with current plant and animal sources. Benefits include mass scalability, low CO2 emissions, and significantly reduced land and freshwater use per unit protein. Microalgae are already used as food products and numerous species exhibit high total protein contents and well-balanced essential amino acid (EAA) compositions for human dietary requirements. Microalgae proteins are also bioavailable for human digestion, and downstream processing steps are likely to further enhance protein digestibility. Species, cultivation, and process/product optimisation are actively being developed to enhance their nutritional, social, and environmental benefits.

Associations of protein intake, sources and distribution on muscle strength in community-dwelling older adults living in Auckland, New Zealand

Protein intake, sources and distribution impact on muscle protein synthesis and muscle mass in older adults. However, it is less clear whether dietary protein influences muscle strength. Data were obtained from the Researching Eating Activity and Cognitive Health (REACH) study, a cross-sectional study aimed at investigating dietary patterns, cognitive function and metabolic syndrome in older adults aged 65-74 years. Dietary intake was assessed using a 4-d food record and muscle strength using a handgrip strength dynamometer. After adjusting for confounders, in female older adults (n 212), total protein intake (β = 0⋅22, P < 0⋅01); protein from dairy and eggs (β = 0⋅21, P = 0⋅03) and plant food sources (β = 0⋅60, P < 0⋅01); and frequently consuming at least 0⋅4 g/kg BW per meal (β = 0⋅08, P < 0⋅01) were associated with higher BMI-adjusted muscle strength. However, protein from meat and fish intake and the coefficient of variance of protein intake were not related to BMI-muscle strength in female older adults. No statistically significant associations were observed in male participants (n = 113). There may be sex differences when investigating associations between protein intake and muscle strength in older adults. Further research is needed to investigate these sex differences.

Eggs: Healthy or Risky? A Review of Evidence from High Quality Studies on Hen's Eggs

Hen's eggs (from Gallus gallus domesticus) provide choline, folate, vitamin D, iodine, B vitamins and high-quality protein and are no longer viewed by national bodies as a risk factor for hypercholesterolaemia and cardiovascular disease (CVD). Yet, questions remain about the benefits and risks of eating eggs regularly. This review evaluates recent high-quality evidence from randomised controlled trials (RCT) and meta-analyses of observational studies and considers new areas of interest, such as weight management, protein metabolism, allergy risk and sustainability. In several RCT, eggs increased muscle protein synthesis and lowered fat mass, which could support optimal body composition. Eggs within a meal improved satiety, which could translate into lower energy intakes, although more RCT are needed. In observational studies, higher egg consumption was associated with a null effect or a modest reduced risk of CVD. For type 2 diabetes (T2D) incidence and risk of CVD in people with T2D, there were inconsistencies between observational and RCT data, with the former noting positive associations and the latter seeing no effect of higher egg intake on markers of T2D and CVD. Sustainability metrics suggest that eggs have the lowest planetary impact amongst animal proteins. To lower allergy risk, earlier introduction of eggs into weaning diets is warranted. In conclusion, the balance of evidence points to eggs being a nutritious food suggesting there are broad health benefits from including eggs in the diet at intakes higher than that currently consumed by European populations.

Understanding consumer liking of beef patties with different firmness among younger and older adults using FaceReader™ and biometrics

Sensorial perceptions change as people age and biometrics analysis can be used to explore the unconscious consumer responses. Investigation was conducted of effects of consumer age (younger, 22-52 years; older, 60-76 years) on facial expression response (FER) during consumption of beef patties with varying firmness (soft, medium, hard) and taste (±plum sauce). Video images were collected and FERs analysed using FaceReader™. Younger people exhibited higher intensity for happy/sad/scared and lower intensity for neutral/disgusted, relative to older people. Interactions between age and texture/sauce showed little FER variation in older people, whereas younger people showed considerable FER variation. Younger people, but not older people, had lowest intensity of happy FER and highest intensity of angry FER for the hard patty. Sauce addition resulted in higher intensity of happy/contempt in younger consumers, but not older consumers. FER collected using FaceReader™ was successfully used to differentiate between the unconscious responses of younger and older consumers.

The Health Benefits of Egg Protein

Once the general public accepts that dietary cholesterol is not a concern for cardiovascular disease risk, foods that have been labeled as high-cholesterol sources, including eggs, may be appreciated for their various other dietary components. One of the nutrients in eggs that deserves further discussion is egg protein. Egg protein has been recognized to be highly digestible and an excellent source of essential amino acids, with the highest attainable protein digestibility-corrected amino acid score. Egg protein has been shown to decrease malnutrition in underdeveloped countries, possibly increase height in children, and protect against kwashiorkor. Egg protein has been demonstrated to be important to skeletal muscle health and protective against sarcopenia. Egg protein also can decrease appetite, resulting in a reduction in the caloric intake from the next meal and weight reduction. Other protective effects of egg protein addressed in this review include protection against infection as well as hypotensive and anti-cancer effects.

Plant-based diets and risk of frailty in community-dwelling older adults: the Seniors-ENRICA-1 cohort

Frailty is a geriatric syndrome that leads to increased risk of hospitalization, disability, and death. The effect of plant-based diets defined by the quality of their plant foods is unclear. Our objective is to study the association between two plant-based diet indices and the occurrence of frailty among community-dwelling older adults in Spain. We analyzed data from 1880 individuals aged ≥ 60 years from the Spanish Seniors ENRICA-1 cohort. We used a validated diet history to build two indices: (a) the healthful Plant-based Diet Index (hPDI) where healthy plant foods received positive scores, whereas less-healthy plant foods and animal foods received reverse scores; and (b) the unhealthful Plant-based Diet Index (uPDI), with positive scores to less-healthy plant foods and reverse scores to animal and healthy plant foods. Incident frailty was defined with the Fried phenotype. Study associations were summarized with odds ratios (OR) and 95% confidence intervals (CI) obtained from multivariable logistic models. After 3.3 years of follow-up, 136 incident frailty cases were ascertained. Comparing the highest vs. the lowest tertile of adherence, the OR [95% CI] for frailty was 0.43 (0.25-0.74; p-trend = .003) for the hPDI, and 2.89 (1.73-4.84; p-trend < .001) for the uPDI. Higher consumption of healthy plant foods was inversely associated with frailty (0.39 [0.23-0.66; p-trend < 0.001]); higher consumption of unhealthy plant foods was associated with higher frailty risk (2.40 [1.23-4.71; p-trend = .01]). In older adults, the hPDI was associated with lower risk of frailty, while the opposite was found for the uPDI.

A lacto-ovo-vegetarian dietary pattern is protective against sarcopenic obesity: A cross-sectional study of elderly Chinese people

OBJECTIVES

The purpose of this study was to investigate the correlation between dietary patterns and the risk of sarcopenic obesity (SO) in community-dwelling elderly people.

METHODS

SO was defined as the coexistence of sarcopenia and obesity. Participants with low skeletal muscle index, low muscle strength, or low physical performance were diagnosed with sarcopenia, whereas obesity was defined as waist circumference ≥85 cm in men and ≥80 cm in women. Dietary patterns were determined by principal component analysis. Multinomial logistic regression analysis was used to evaluate the relationship between dietary patterns and SO.

RESULTS

Among 3795 Chinese participants, 112 (3.0%) were diagnosed with SO. After adjustment for confounding variables, lacto-ovo-vegetarian dietary pattern was negatively associated with risk of SO. The odds ratio for SO was 0.79 (95% confidence interval, 0.65-0.97; P = 0.027) for the lacto-ovo-vegetarian dietary pattern, whereas meat-fish and junk food dietary patterns were not associated with the risk of SO.

CONCLUSIONS

We suggest that older people should have a balanced daily diet such as a lacto-ovo-vegetarian dietary pattern to prevent the occurrence and progression of SO.

Dietary and Lifestyle Factors Modulate the Activity of the Endogenous Antioxidant System in Patients with Age-Related Macular Degeneration: Correlations with Disease Severity

Age-related macular degeneration (AMD) is a common cause of blindness in the elderly population, but the pathogenesis of this disease remains largely unknown. Since oxidative stress is suggested to play a major role in AMD, we aimed to assess the activity levels of components of the antioxidant system in patients with AMD. We also investigated whether lifestyle and dietary factors modulate the activity of these endogenous antioxidants and clinical parameters of disease severity. We recruited 330 patients with AMD (39 with early, 100 with intermediate and 191 with late form of AMD) and 121 controls in this study. At enrolment, patients’ dietary habits and physical activity were assessed, and each study participant underwent a thorough ophthalmologic examination. The activity of several components of the antioxidant system were measured in red blood cells and platelets using both kinetic and spectrophotometric methods. Patients with AMD consumed much lower levels of fatty fish and eggs than the control group (p = 0.008 and p = 0.04, respectively). In the nAMD group, visual acuity (VA) correlated positively with green vegetable consumption (Rs = +0.24, p = 0.004) and omega-3-rich oil intake (Rs = +0.17, p = 0.03). In the AMD group, the total physical activity MET score correlated positively with VA (Rs = +0.17, p = 0.003) and correlated negatively with the severity of AMD (Rs = −0.14, p = 0.01). A multivariate analysis of patients and controls adjusted for age, sex, and smoking status (pack-years) revealed that AMD was an independent variable associated with a lower RBC catalase (β = −0.37, p < 0.001) and higher PLT catalase (β = +0.25, p < 0.001), RBC GPx (β = +0.26, p < 0.001), PLT GPx (β = +0.16, p = 0.001), RBC R-GSSG (β = +0.13, p = 0.009), PLT R-GSSG (β = +0.12, p = 0.02) and RBC GSH transferase (β = +0.23, p < 0.001) activity. The activities of components of the antioxidant system were associated with disease severity and depended on dietary habits. The observed substantial increase in the activity of many critical endogenous antioxidants in patients with AMD further indicates that the required equilibrium in the antioxidant system is disturbed throughout the course of the disease. Our findings explicitly show that a diet rich in green vegetables, fish and omega-3-rich oils, supplemented by physical exercise, is beneficial for patients with AMD, as it might delay disease progression and help retain better visual function.

The provision of recipes and single-use herb/spice packets to increase egg and protein intake in community-dwelling older adults: a randomised controlled trial

OBJECTIVE

This study investigated the impact of recipe and single-use herb/spice packet provision on egg intake and protein intake in community-dwelling individuals aged over 55 years.

DESIGN

Using a randomised-controlled intervention design, 100 older adults were randomised to receive (n 53) or not receive (n 47) high-protein egg-based recipes and herb/spice packets through the post for 12 weeks, from June to December 2016. Egg intake, protein intake, adverse events, lean body mass and functional measures of lean body mass were measured at baseline, after the 12 weeks and after a further 12 weeks.

SETTING

Bournemouth, UK.

PARTICIPANTS

Community-dwelling older adults.

RESULTS

Intention-to-treat data were analysed using regression, controlling for various demographic and lifestyle characteristics. Ninety-three individuals (intervention, n 50; control, n 43) completed assessments at all three time points. Egg intakes increased by end of intervention in both groups (mean: 4-5 eggs/month). After a further 12 weeks, higher egg intakes were sustained in the intervention group, while egg intakes in the control group returned to baseline levels (between-group difference: β = -0·124, P = 0·047). No differences were found in other measures (largest β = -0·106, P = 0·12).

CONCLUSIONS

The provision of high-protein egg-based recipes and single-use herb/spice packets over 12 weeks increased egg intakes up to 12 weeks after end of intervention. Other factors may explain increased egg intakes during the intervention, but the sustained effects most plausibly result directly from recipe provision. Limited effects in other measures suggest that the recipes may have replaced as opposed to added to existing protein intakes.

Dietary Oily Fish Intake and Frailty. A Population-Based Study in Frequent Fish Consumers Living in Rural Coastal Ecuador (the Atahualpa Project)

Oily fish are recommended as part of a healthy diet due to their high content of long-chain omega-3 polyunsaturated fatty acids (ω-3 PUFAs), proteins, and other nutrients. There is preliminary evidence of beneficial effects of ω-3 PUFAs in the prevention of sarcopenia (a major component of frailty). In this study, we aimed to assess the relationship between dietary oily fish intake and a measure of frailty - the Edmonton Frail Scale (EFS) score - in community-dwelling older adults living in rural coastal Ecuador. A total of 363 Atahualpa residents were enrolled. The mean fish servings per week were 8.8 ± 5.2 and mean EFS score was 5 ± 2.8 points. A linear regression model showed no association between the amount of oily fish intake and EFS scores. However, an interaction model, with participants stratified according to their median age and fish intake in quintiles, showed a significant effect for both variables on the EFS score (ß coefficient = 0.104; 95% C.I.: 0.003-0.206; p = 0.044). At the lowest quintile of fish intake, younger individuals have lower EFS scores than their older counterparts. As the consumption of oily fish increases, mean EFS scores margins were found to be progressively reduced in subjects aged 60-69 years but were largely unaffected in persons aged ≥70 years. It appears that oily fish intake has a positive effect on the frailty status of younger subjects but is superseded by the effects of age in the older population.

Consumption of eggs and the 15-year incidence of age-related macular degeneration

BACKGROUND AND AIMS

A naturally rich source of lutein and zeaxanthin are eggs. There is scarce epidemiological data on the temporal association between total egg consumption and age-related macular degeneration (AMD) incidence. We aimed to establish the prospective and independent association between consumption of eggs with the incidence of AMD over a 15-year follow-up.

METHODS

In this population-based cohort study of 3,654 participants aged 49 + years examined at baseline, 2034 participants had complete information on baseline egg consumption and AMD signs over 15 years. AMD was determined from retinal photographs. Egg consumption was assessed using a semi-quantitative food-frequency questionnaire. Total egg intake was calculated through summing up intakes in all forms e.g. boiled, poached, fried, scrambled and/or omelette. We summarized total egg consumption into the following categories: ≤1 egg/week; 2-4 eggs/week; 5-6 eggs/week; and ≥1 egg/day.

RESULTS

At baseline, participants who consumed 2-4 eggs/week compared to those who consumed ≤1 egg/week (reference group) had reduced risk of incident late-stage AMD after 15 years: multivariable-adjusted odds ratio, OR, 0.51 (95% confidence intervals, CI, 0.28-0.92). Participants who consumed 2-4 eggs/week versus ≤1 egg/week at baseline had 62% reduced risk of developing neovascular AMD. Among those whose AMD onset was at or before the 10-year follow-up, consumption of 2-4 and 5-6 eggs/week was associated with 54% and 65% reduced risk of incident late AMD, respectively. When analyzed as a dichotomized variable, participants who consumed >1 egg/week versus ≤1 egg/week at baseline, had 46% reduced risk of developing late-stage AMD 15 years later: multivariable-adjusted OR 0.54 (95% CI 0.3-0.90). Non-significant associations were observed between egg consumption and incident early AMD.

CONCLUSIONS

Our findings suggest that moderate consumption of eggs significantly reduces the risk of developing incident late-stage AMD over 15 years.

Egg Intake in Chronic Kidney Disease

Patients with chronic kidney disease (CKD) are often instructed to adhere to a renal-specific diet depending on the severity and stage of their kidney disease. The prescribed diet may limit certain nutrients, such as phosphorus and potassium, or encourage the consumption of others, such as high biological value (HBV) proteins. Eggs are an inexpensive, easily available and high-quality source of protein, as well as a rich source of leucine, an essential amino acid that plays a role in muscle protein synthesis. However, egg yolk is a concentrated source of both phosphorus and the trimethylamine N-oxide precursor, choline, both of which may have potentially harmful effects in CKD. The yolk is also an abundant source of cholesterol which has been extensively studied for its effects on lipoprotein cholesterol and the risk of cardiovascular disease. Efforts to reduce dietary cholesterol to manage dyslipidemia in dialysis patients (already following a renal diet) have not been shown to offer additional benefit. There is a paucity of data regarding the impact of egg consumption on lipid profiles of CKD patients. Additionally, egg consumption has not been associated with the risk of developing CKD based on epidemiological studies. The egg yolk also contains bioactive compounds, including lutein, zeaxanthin, and vitamin D, which may confer health benefits in CKD patients. Here we review research on egg intake and CKD, discuss both potential contraindications and favorable effects of egg consumption, and describe the need for further research examining egg intake and outcomes in the CKD and end-stage renal disease population.

Towards a Food-Based Intervention to Increase Protein Intakes in Older Adults: Challenges to and Facilitators of Egg Consumption

Abstract: Background: Dietary protein intake is important for health. Eggs, as a protein-rich food with characteristics that appeal to older adults, may provide opportunities for increasing protein intake. Interventions that focus on the challenges or facilitators that affect a large proportion of the population will be of increased impact on a population-wide scale. This work aimed to investigate the relative importance of a number of challenges to and facilitators of egg consumption in a UK population-wide sample of older adults.

METHODS

A cross-sectional postal questionnaire, measuring habitual egg intake, reasons for eating/not eating eggs and a range of demographic and lifestyle characteristics, was administered by post to 1082 older adults.

RESULTS

230 questionnaires suitable for analysis were returned (110 females, ages 55⁻80+ years). Habitual egg intake ranged from 1⁻89 eggs/month, mean (standard deviation) = 18 (13) eggs/month. Reasons for eating/not eating eggs were reduced using Principal Components Analysis to 23 challenges and facilitators of egg consumption. Regression analyses revealed habitual egg intake to be associated with 10 challenges and facilitators (smallest β = 0.14, p = 0.04), and with protein consumption, age and Body Mass Index (smallest β = 0.14, p = 0.03).

DISCUSSION

Many possibilities for future intervention based on existing challenges or facilitators were found. Our results suggest that strategies to increase egg consumption in older adults should focus on: improving liking, tastiness and adding variety; promoting eggs as an everyday type of food; reducing stereotypes about who does and who does not consume eggs; and promoting eggs for people who have noticed the effects of ageing on their food intake. Strategies that highlight value-for-money may be counterproductive. Future work evaluating the value of these strategies for improving protein intake in this age group would be of value.

Could Eggs Help Increase Dietary Protein Intake in Older Adults? - Exploring Reasons for the Consumption and Non-Consumption of Eggs in People over 55 years old

Compared to other protein-rich foods, eggs are of soft texture, easy to cook, and low cost, and may be useful in increasing protein intakes in older adults. Focus groups and interviews were used to explore all reasons for consuming and not consuming eggs in older adults. Forty-two individuals (20 males, 22 females, aged 56-96 years) took part in one of eight focus groups or two individual interviews. Thematic analyses revealed 69 different reasons for eating or not eating eggs in this population. Reasons were related to: hedonics, properties of the food, preparation style, convenience, physical environment, variety, physical health/abilities, nutrition and health knowledge, food safety, social environment, morality, emotion, and habit. Some of these reasons are likely to be specific to egg consumption in older adults, e.g. properties of the food and convenience combined with physical health/abilities. Some reasons are also likely to be more relevant to older than younger individuals, e.g. medical factors. Investigation of the reasons most related to intake on a population-wide scale would aid the development of interventions.