A higher protein intake at breakfast and lunch is associated with a higher total daily protein intake in older adults: a post-hoc cross-sectional analysis of four randomised controlled trials.

BACKGROUND: A protein intake of 30-40 g per meal is suggested to maximally stimulate muscle protein synthesis in older adults and could therefore contribute to the prevention of sarcopenia. Protein intake at breakfast and lunch is often low and offers a great opportunity to improve daily protein intake. Protein, however, is known for its satiating effects. Therefore, we explored the association between the amount of protein intake at breakfast and lunch and total daily protein intake in older adults. METHODS: Protein intake was assessed by a 3-day food record in 498 community dwelling older adults (≥55 years) participating different lifestyle interventions. Linear mixed model analysis was used to examine the association between protein intake at breakfast or lunch and total daily protein intake, adjusted for sex, age, body mass index, smoking status, study and total energy intake. RESULTS: After adjustment for potential confounders, a 10 g higher protein intake at breakfast was associated with a 3.2 g higher total daily protein intake (P = 0.008) for males and a 4.9 g (P < 0.001) higher total daily protein intake for females. A 10 g higher protein intake at lunch was associated with a 3.7 g higher total daily protein intake (P < 0.001) for males, and a 5.8 g higher total daily protein intake (P < 0.001) for females. CONCLUSIONS: A higher protein intake at breakfast and lunch is associated with a higher total daily protein intake in community dwelling older adults. Stimulating a higher protein intake at breakfast and lunch might represent a promising nutritional strategy to optimise the amount of protein per meal without compromising total daily protein intake.

Physical activity, dietary intake and quality of life during COVID-19 lockdown in patients awaiting transcatheter aortic valve implantation.

BACKGROUND: The COVID-19 pandemic has led to a national lockdown in the Netherlands, which also affected transcatheter aortic valve implantation (TAVI) patients. The objective of the study was to describe physical activity, dietary intake and quality of life (QoL) in patients on the waiting list for TAVI pre-lockdown and during lockdown. METHODS: Consecutive patients awaiting TAVI at the Amsterdam University Medical Centers, the Netherlands were included. Measurements were self-reported effect of lockdown, physical activity, dietary intake and QoL. RESULTS: In total, 58 patients (median age 80, interquartile range (IQR) 76-84, 45% female) were observed pre-lockdown and 16 patients (median age 78, IQR 76-82, 25% female) during lockdown. Ten of the 16 patients during lockdown reported a decline in physical activity. However, we observed a median number of 5861 steps a day (IQR 4579-7074) pre-lockdown and 8404 steps a day (IQR 7653-10,829) during lockdown. Median daily protein intake was 69 g (IQR 59-82) pre-lockdown and 90 g (IQR 68-107) during lockdown. Self-rated health on a visual analogue scale was 63 points (IQR 51-74) pre-lockdown and 73 points (IQR 65-86) during lockdown. CONCLUSIONS: More than half of the patients during lockdown reported less physical activity, while we observed a higher number of steps a day, a similar dietary intake and a higher QoL. Therefore, patients on the TAVI waiting list appeared to be able to cope with the lockdown measures.

The impact of protein quantity during energy restriction on genome-wide gene expression in adipose tissue of obese humans.

BACKGROUND: Overweight and obesity is a growing health problem worldwide. The most effective strategy to reduce weight is energy restriction (ER). ER has been shown to be beneficial in disease prevention and it reduces chronic inflammation. Recent studies suggest that reducing the protein quantity of a diet contributes to the beneficial effects by ER. The organ most extensively affected during ER is white adipose tissue (WAT). OBJECTIVE: The first objective was to assess changes in gene expression between a high-protein diet and a normal protein diet during ER. Second, the total effect of ER on changes in gene expression in WAT was assessed. METHODS: In a parallel double-blinded controlled study, overweight older participants adhered to a 25% ER diet, either combined with high-protein intake (HP-ER, 1.7 g kg-1 per day), or with normal protein intake (NP-ER, 0.9 g kg-1 per day) for 12 weeks. From 10 HP-ER participants and 12 NP-ER participants subcutaneous WAT biopsies were collected before and after the diet intervention. Adipose tissue was used to isolate total RNA and to evaluate whole-genome gene expression changes upon a HP-ER and NP-ER diet. RESULTS: A different gene expression response between HP-ER and NP-ER was observed for 530 genes. After NP-ER, a downregulation in expression of genes linked to immune cell infiltration, adaptive immune response and inflammasome was found, whereas no such effect was found after HP-ER. HP-ER resulted in upregulation in expression of genes linked to cell cycle, GPCR signalling, olfactory signalling and nitrogen metabolism. Upon 25% ER, gene sets related to energy metabolism and immune response were decreased. CONCLUSIONS: Based on gene expression changes, we concluded that consumption of normal protein quantity compared with high-protein quantity during ER has a more beneficial effect on inflammation-related gene expression in WAT.

Protein intake and lean body mass preservation during energy intake restriction in overweight older adults.

BACKGROUND: Dietary-induced weight loss is generally accompanied by a decline in skeletal muscle mass. The loss of muscle mass leads to a decline in muscle strength and impairs physical performance. A high dietary protein intake has been suggested to allow muscle mass preservation during energy intake restriction. OBJECTIVE: To investigate the impact of increasing dietary protein intake on lean body mass, strength and physical performance during 12 weeks of energy intake restriction in overweight older adults. DESIGN: Sixty-one overweight and obese men and women (63±5 years) were randomly assigned to either a high protein diet (HP; 1.7 g kg(-1) per day; n=31) or normal protein diet (NP; 0.9 g kg(-1) per day; n=30) during a 12-week 25% energy intake restriction. During this controlled dietary intervention, 90% of the diet was provided by the university. At baseline and after the intervention, body weight, lean body mass (dual-energy X-ray absorptiometry), leg strength (1-repetition maximum), physical performance (Short Physical Performance Battery, 400 m) and habitual physical activity (actigraph) were assessed. RESULTS: Body weight declined in both groups with no differences between the HP and NP groups (-8.9±2.9 versus -9.1±3.4 kg, respectively; P=0.584). Lean body mass declined by 1.8±2.2 and 2.1±1.4 kg, respectively, with no significant differences between groups (P=0.213). Leg strength had decreased during the intervention by 8.8±14.0 and 8.9±12.8 kg, with no differences between groups (P=0.689). Physical performance as measured by 400 m walking speed improved in both groups, with no differences between groups (P=0.219). CONCLUSIONS: Increasing protein intake above habitual intake levels (0.9 g kg(-1) per day) does not preserve lean body mass, strength or physical performance during prolonged energy intake restriction in overweight older adults.

GLIM-based malnutrition, protein intake and diet quality in preprocedural Transcatheter Aortic Valve Implantation (TAVI) patients.

BACKGROUND & AIMS: Diagnosed prevalence of malnutrition and dietary intake are currently unknown in patients with severe aortic stenosis planned to undergo Transcatheter Aortic Valve Implantation (TAVI). This study describes the preprocedural nutritional status, protein intake and diet quality. METHODS: Consecutive preprocedural TAVI patients were asked to participate in this explorative study. Nutritional status was diagnosed with the global leadership initiative on malnutrition (GLIM) criteria. Preprocedural protein intake and diet quality were assessed with a three-day dietary record. To increase the record's validity, a researcher visited the participants at their homes to confirm the record. Protein intake was reported as an average intake of three days and diet quality was assessed using the Dutch dietary guidelines (score range 0-14, 1 point for adherence to each guideline). RESULTS: Of the included patients (n = 50, median age 80 ± 5, 56% male) 32% (n = 16) were diagnosed with malnutrition. Patients diagnosed with malnutrition had a lower protein intake (1.02 ± 0.28 g/kg/day vs 0.87 ± 0.21 g/kg/day, p = 0.04). The difference in protein intake mainly took place during lunch (20 ± 13 g/kg vs 13 ± 7 g/kg, p = 0.03). Patients adhered to 6.4 ± 2.2 out of 14 dietary guidelines. Adherence to the guideline of whole grains and ratio of whole grains was lower in the group of patients with malnutrition than in patients with normal nutritional status (both 62% vs 19%, p = 0.01). In a multivariate analysis diabetes mellitus was found as an independent predictor of malnutrition. CONCLUSION: Prevalence of malnutrition among TAVI patients is very high up to 32%. Patients with malnutrition had lower protein and whole grain intake than patients with normal nutritional status. Furthermore, we found diabetes mellitus as independent predictor of malnutrition. Nutrition interventions in this older patient group are highly warranted.

The Impact of Dietary Protein or Amino Acid Supplementation on Muscle Mass and Strength in Elderly People: Individual Participant Data and Meta-Analysis of RCT's.

OBJECTIVES: Increasing protein or amino acid intake has been promoted as a promising strategy to increase muscle mass and strength in elderly people, however, long-term intervention studies show inconsistent findings. Therefore, we aim to determine the impact of protein or amino acid supplementation compared to placebo on muscle mass and strength in older adults by combining the results from published trials in a meta-analysis and pooled individual participant data analysis. DESIGN: We searched Medline and Cochrane databases and performed a meta-analysis on eight available trials on the effect of protein or amino acid supplementation on muscle mass and strength in older adults. Furthermore, we pooled individual data of six of these randomized double-blind placebo-controlled trials. The main outcomes were change in lean body mass and change in muscle strength for both the meta-analysis and the pooled analysis. RESULTS: The meta-analysis of eight studies (n=557) showed no significant positive effects of protein or amino acid supplementation on lean body mass (mean difference: 0.014 kg: 95% CI -0.152; 0.18), leg press strength (mean difference: 2.26 kg: 95% CI -0.56; 5.08), leg extension strength (mean difference: 0.75 kg: 95% CI: -1.96, 3.47) or handgrip strength (mean difference: -0.002 kg: 95% CI -0.182; 0.179). Likewise, the pooled analysis showed no significant difference between protein and placebo treatment on lean body mass (n=412: p=0.78), leg press strength (n=121: p=0.50), leg extension strength (n=121: p=0.16) and handgrip strength (n=318: p=0.37). CONCLUSIONS: There is currently no evidence to suggest that protein or amino acid supplementation without concomitant nutritional or exercise interventions increases muscle mass or strength in predominantly healthy elderly people.

The impact of 1-year vitamin D supplementation on vitamin D status in athletes: a dose-response study.

BACKGROUND/OBJECTIVES: To assess the prevalence of vitamin D deficiency in Dutch athletes and to define the required dosage of vitamin D3 supplementation to prevent vitamin D deficiency over the course of a year. SUBJECTS/METHODS: Blood samples were collected from 128 highly trained athletes to assess total 25(OH)D concentration. Of these 128 athletes, 54 male and 48 female athletes (18-32 years) were included in a randomized, double blind, dose-response study. Athletes with either a deficient (<50 nmol/l) or an insufficient (50-75 nmol/l) 25(OH)D concentration were randomly assigned to take 400, 1100 or 2200 IU vitamin D3 per day orally for 1 year. Athletes who had a total 25(OH)D concentration above 75 nmol/l at baseline continued with the study protocol without receiving vitamin D supplements. Serum total 25(OH)D concentration was assessed every 3 months, as well as dietary vitamin D intake and sunlight exposure. RESULTS: Nearly 70% of all athletes showed an insufficient (50-75 nmol/l) or a deficient (<50 nmol/l) 25(OH)D concentration at baseline. After 12 months, serum 25(OH)D concentration had increased more in the 2200 IU/day group (+50±27 nmol/l) than the sufficient group receiving no supplements (+4±17 nmol/l; P<0.01) and the 1100 IU/day group (+25±23 nmol/l; P<0.05). Supplementation with 2200 IU/day vitamin D resulted in a sufficient 25(OH)D concentration in 80% of the athletes after 12 months. CONCLUSIONS: Vitamin D deficiency is highly prevalent in athletes. Athletes with a deficient or an insufficient 25(OH)D concentration can achieve a sufficient 25(OH)D concentration within 3 months by taking 2200 IU/day.

Bio-impedance analysis for appendicular skeletal muscle mass assessment in (pre-) frail elderly people.

BACKGROUND & AIMS: Screening populations for skeletal muscle mass (SMM) is important for early detection of sarcopenia. Our aim was to develop an age specific bio-impedance (BI) prediction equation for the assessment of appendicular skeletal muscle mass (ASMM) in (pre-) frail elderly people aged 65 and older. METHODS: Anthropometric, BI and dual-energy X-ray absorptiometry (DEXA) measurements from 106 (pre-) frail elderly subjects (61 females and 45 males, aged 65-96 years) were used to derive three ASMM prediction equations using multiple regression analysis: one for single frequency BI measurements at 50 kHz (ASMM50kHz), one for measurements at the characteristic frequency (ASMMFc) and one for bioelectrical impedance spectroscopy (ASMMBIS). The same data was used to evaluate an existing prediction equation. RESULTS: ASMM50kHz had the best fitting model (r2adj = 0.923, SEE = 1.19 and a PRESS value = 163.4), followed by ASMMFc (r2adj = 0.915, SEE = 1.25 and a PRESS value = 175.9) and ASMMBIS (r2adj = 0.915, SEE = 1.26 and a PRESS value = 177.1). Average ASMM measured by DEXA and both ASMM50kHz and ASMMFc were comparable. ASMMBIS tended to underestimate ASMM slightly. An existing prediction equation had a tendency to underestimate ASMM in people with a lower amount of ASMM and overestimate ASMM in people with a higher amount of ASMM. CONCLUSIONS: ASMM50kHz was able to measure average ASMM within our population of (pre-) frail elderly in a valid way. However, its predictive power on both individual and population level needs to be confirmed in an independent and larger (pre-) frail elderly population and across multiple institutions and ethnic groups.

Lean Mass Appears to Be More Strongly Associated with Bone Health than Fat Mass in Urban Black South African Women.

OBJECTIVES: To examine the association between body composition (fat mass, lean mass and body mass index, BMI) and bone health (bone mineral density, BMD and fracture risk) in urban black South African women. DESIGN: A cross sectional study examining associations between body composition, dietary intake (food frequency questionnaire), habitual physical activity (Activity energy expenditure (AEE) measured using an accelerometer with combined heart rate monitor and physical activity questionnaire) and bone health (BMD using dual-energy X ray absorptiometry, DXA and fracture risk). SETTING: Urban community dwellers from Ikageng in the North-West Province of South Africa. PARTICIPANTS: One hundred and eighty nine (189) healthy postmenopausal women aged ≥43 years. RESULTS: Fat mass and lean mass were significantly associated with BMD and fracture risk when adjusted for potential confounders. However, lean mass and not fat mass remained significantly associated with femoral neck BMD (ß = 0.49, p <0.001), spine BMD (ß = 0.48, p< 0.0001) and hip BMD (ß = 0.59, p< 0.0001). Lean mass was also negatively associated with fracture risk (ß = -0.19 p =0.04) when both lean and fat mass were in the same model. CONCLUSION: Lean mass and fat mass were positively associated with femoral neck, spine and hip BMDs and negatively associated with fracture risk in urban black South African women. Our finding suggests that increasing lean mass rather than fat mass is beneficial to bone health. Our study emphasises the importance of positive lifestyle changes, intake of calcium from dairy and adequate weight to maintain and improve bone health of postmenopausal women.

Low vitamin D status is associated with reduced muscle mass and impaired physical performance in frail elderly people.

BACKGROUND/OBJECTIVES: Serum 25-hydroxyvitamin D (25(OH)D) status has been associated with muscle mass, strength and physical performance in healthy elderly people. Yet, in pre-frail and frail elderly people this association has not been studied. The objective of this study was to explore the association between vitamin D intake and serum 25(OH)D status with muscle mass, strength and physical performance in a pre-frail and frail elderly population. SUBJECTS/METHODS: This cross-sectional study included 127 pre-frail and frail elderly people in The Netherlands. Whole body and appendicular lean mass (ALM) (dual energy X-ray absorptiometry), leg strength (one repetition maximum), handgrip strength and physical performance (short physical performance battery) were measured, and blood samples were collected for the assessment of serum 25(OH)D status (liquid chromatography-tandem mass spectrometry). In addition, habitual dietary intake (3-day food records) and physical activity data (accelerometers) were collected. RESULTS: In total, 53% of the participants had a serum 25(OH)D level below 50 nmol/l. After adjustment for confounding factors, 25(OH)D status was associated with ALM (ß=0.012, P=0.05) and with physical performance (ß=0.020, P<0.05). Vitamin D intake was associated with physical performance (ß=0.18, P<0.05) but not with ALM (P>0.05). CONCLUSION: In this frail elderly population, 25(OH)D status is low and suggests a modest association with reduced ALM and impaired physical performance. In addition, vitamin D intake tended to be associated with impaired physical performance. Our findings highlight the need for well-designed intervention trials to assess the impact of vitamin D supplementation on 25(OH)D status, muscle mass and physical performance in pre-frail and frail elderly people.