Protein Intake at Twice the RDA in Older Men Increases Circulatory Concentrations of the Microbiome Metabolite Trimethylamine-N-Oxide (TMAO)

Higher dietary protein intake is increasingly recommended for the elderly; however, high protein diets have also been linked to increased cardiovascular disease (CVD) risk. Trimethylamine-N-oxide (TMAO) is a bacterial metabolite derived from choline and carnitine abundant from animal protein-rich foods. TMAO may be a novel biomarker for heightened CVD risk. The purpose of this study was to assess the impact of a high protein diet on TMAO. Healthy men (74.2 ± 3.6 years, n = 29) were randomised to consume the recommended dietary allowance of protein (RDA: 0.8 g protein/kg bodyweight/day) or twice the RDA (2RDA) as part of a supplied diet for 10 weeks. Fasting blood samples were collected pre- and post-intervention for measurement of TMAO, blood lipids, glucose tolerance, insulin sensitivity, and inflammatory biomarkers. An oral glucose tolerance test was also performed. In comparison with RDA, the 2RDA diet increased circulatory TMAO (p = 0.002) but unexpectedly decreased renal excretion of TMAO (p = 0.003). LDL cholesterol was increased in 2RDA compared to RDA (p = 0.049), but no differences in other biomarkers of CVD risk and insulin sensitivity were evident between groups. In conclusion, circulatory TMAO is responsive to changes in dietary protein intake in older healthy males.

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Obesity Status Affects the Relationship Between Protein Intake and Insulin Sensitivity in Late Pregnancy

Nutrients ◽

10.3390/nu11092190 ◽

2019 ◽

Vol 11 (9) ◽

pp. 2190 ◽

Cited By ~ 2

Author(s):

Allman ◽

Diaz Fuentes ◽

Williams ◽

Turner ◽

Andres ◽

...

Keyword(s):

Insulin Sensitivity ◽

Early Pregnancy ◽

Dietary Protein ◽

Protein Intake ◽

Late Pregnancy ◽

Oral Glucose ◽

Metabolic Clearance ◽

Dietary Protein Intake ◽

Food Record ◽

The Relationship

The purpose of this study was to determine the associations between amount and type of dietary protein intake and insulin sensitivity in late pregnancy, in normal weight and overweight women (29.8 ± 0.2 weeks gestation, n = 173). A 100-gram oral glucose tolerance test (OGTT) was administered following an overnight fast to estimate the metabolic clearance rate of glucose (MCR, mg · kg-1 · min-1) using four different equations accounting for the availability of blood samples. Total (TP), animal (AP), and plant (PP) protein intakes were assessed using a 3-day food record. Two linear models with MCR as the response variable were fitted to the data to estimate the relationship of protein intake to insulin sensitivity either unadjusted or adjusted for early pregnancy body mass index (BMI) because of the potential of BMI to influence this relationship. There was a positive association between TP (β = 1.37, p = 0.002) and PP (β = 4.44, p < 0.001) intake in the last trimester of pregnancy and insulin sensitivity that weakened when accounting for early pregnancy BMI. However, there was no relationship between AP intake and insulin sensitivity (β = 0.95, p = 0.08). Therefore, early pregnancy BMI may be a better predictor of insulin sensitivity than dietary protein intake in late pregnancy.

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Dietary Protein Intake Level Modulates Mucosal Healing and Mucosa-Adherent Microbiota in Mouse Model of Colitis

Nutrients ◽

10.3390/nu11030514 ◽

2019 ◽

Vol 11 (3) ◽

pp. 514 ◽

Cited By ~ 8

Author(s):

Sandra Vidal-Lletjós ◽

Mireille Andriamihaja ◽

Anne Blais ◽

Marta Grauso ◽

Patricia Lepage ◽

...

Keyword(s):

Dietary Protein ◽

Protein Intake ◽

High Protein Diet ◽

Repair Process ◽

Mucosal Healing ◽

High Protein ◽

Protein Diet ◽

Dietary Protein Intake ◽

Epithelial Repair ◽

The Impact

Mucosal healing after an inflammatory flare is associated with lasting clinical remission. The aim of the present work was to evaluate the impact of the amount of dietary protein on epithelial repair after an acute inflammatory episode. C57BL/6 DSS-treated mice received isocaloric diets with different levels of dietary protein: 14% (P14), 30% (P30) and 53% (P53) for 3 (day 10), 6 (day 13) and 21 (day 28) days after the time of colitis maximal intensity. While the P53 diet worsened the DSS- induced inflammation both in intensity and duration, the P30 diet, when compared to the P14 diet, showed a beneficial effect during the epithelial repair process by accelerating inflammation resolution, reducing colonic permeability and increasing epithelial repair together with epithelial hyperproliferation. Dietary protein intake also impacted mucosa-adherent microbiota composition after inflammation since P30 fed mice showed increased colonization of butyrate-producing genera throughout the resolution phase. This study revealed that in our colitis model, the amount of protein in the diet modulated mucosal healing, with beneficial effects of a moderately high-protein diet, while very high-protein diet displayed deleterious effects on this process.

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Increased prevalence of β-cell dysfunction despite normal HbA1c in youth and young adults with Turner Syndrome

Hormone Research in Paediatrics ◽

10.1159/000520233 ◽

2021 ◽

Author(s):

Nicole Sheanon ◽

Deborah Elder ◽

Jane Khoury ◽

Lori Casnellie ◽

Iris Gutmark-Little ◽

...

Keyword(s):

Insulin Secretion ◽

Insulin Sensitivity ◽

Glucose Tolerance ◽

Turner Syndrome ◽

P Value ◽

Oral Glucose ◽

Adult Women ◽

Β Cell ◽

Cell Dysfunction ◽

The Impact

Intro: Adult women with Turner syndrome (TS) have a high prevalence of diabetes and β-cell dysfunction that increases morbidity and mortality, but, it is unknown if there is β-cell dysfunction present in youth with TS. This study aimed to determine the prevalence of β-cell dysfunction in youth with TS and the impact of traditional therapies on insulin sensitivity and insulin secretion. Methods: Cross-sectional, observational study recruited 60 girls with TS and 60 healthy controls (HC) matched on pubertal status. Each subject had a history, physical exam and oral glucose tolerance test (OGTT). Oral glucose and c-peptide minimal modeling was used to determine β-cell function. Results: Twenty-one TS girls (35%) met criteria for pre-diabetes. Impaired fasting glucose (IFG) was present in 18% of girls with TS and 2% HC (p-value = 0.0003). Impaired glucose tolerance (IGT) was present in 23% of TS girls and 0% HC (p-value < 0.001). The HbA1c was not different between TS and HC (median 5%, p= 0.42). Youth with TS had significant reductions in insulin sensitivity (SI), β-cell responsivity (Φ), and disposition index (DI) compared to HC. These differences remained significant when controlling for BMI z-score (p-values: 0.0006, 0.002, <0.0001 for SI, Φtotal, DI, respectively). Conclusions: β-cell dysfunction is present in youth with TS compared to controls. The presence of both reduced insulin secretion and insulin sensitivity suggest a unique TS-related glycemic phenotype. Based on the data from this study, we strongly suggest that providers employ serial OGTT to screen for glucose abnormalities in TS youth.

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Effects of protein intake on blood pressure, insulin sensitivity and blood lipids in children: a systematic review

British Journal Of Nutrition ◽

10.1017/s0007114514003699 ◽

2015 ◽

Vol 113 (3) ◽

pp. 383-402 ◽

Cited By ~ 7

Author(s):

Trudy Voortman ◽

Anna Vitezova ◽

Wichor M. Bramer ◽

Charlotte L. Ars ◽

Paula K. Bautista ◽

...

Keyword(s):

Blood Pressure ◽

Insulin Sensitivity ◽

Dietary Protein ◽

Protein Intake ◽

Blood Lipids ◽

Healthy Children ◽

Inverse Association ◽

Dietary Protein Intake ◽

Cross Sectional ◽

Beneficial Effects

High protein intake in early childhood is associated with obesity, suggesting possible adverse effects on other cardiometabolic outcomes. However, studies in adults have suggested beneficial effects of protein intake on blood pressure (BP) and lipid profile. Whether dietary protein intake is associated with cardiovascular and metabolic health in children is unclear. Therefore, we aimed to systematically review the evidence on the associations of protein intake with BP, insulin sensitivity and blood lipids in children. We searched the databases Medline, Embase, Cochrane Central and PubMed for interventional and observational studies in healthy children up to the age of 18 years, in which associations of total, animal and/or vegetable protein intake with one or more of the following outcomes were reported: BP; measures of insulin sensitivity; cholesterol levels; or TAG levels. In the search, we identified 6636 abstracts, of which fifty-six studies met all selection criteria. In general, the quality of the included studies was low. Most studies were cross-sectional, and many did not control for potential confounders. No overall associations were observed between protein intake and insulin sensitivity or blood lipids. A few studies suggested an inverse association between dietary protein intake and BP, but evidence was inconclusive. Only four studies examined the effects of vegetable or animal protein intake, but with inconsistent results. In conclusion, the literature, to date provides insufficient evidence for effects of protein intake on BP, insulin sensitivity or blood lipids in children. Future studies could be improved by adequately adjusting for key confounders such as energy intake and obesity.

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Effectiveness of a Per-Meal Protein Prescription and Nutrition Education with versus without Diet Coaching on Dietary Protein Intake and Muscle Health in Middle-Aged Women

Nutrients ◽

10.3390/nu14020375 ◽

2022 ◽

Vol 14 (2) ◽

pp. 375

Author(s):

Kelley L. Jackson ◽

Sareen S. Gropper ◽

Dennis Hunt ◽

Deborah D’Avolio ◽

David Newman

Keyword(s):

Nutrition Education ◽

Dietary Protein ◽

Protein Intake ◽

Dietary Protein Intake ◽

Speed Test ◽

Significant Difference ◽

Meal Protein ◽

Muscle Health ◽

Chair Rise ◽

The Impact

Sufficient dietary protein intake is vital to maintaining muscle health with aging. Yet protein intake among adults is often inadequate. This study’s main objective was to examine the impact of nutrition education (NE) and a per-meal protein prescription (PRx) with versus without diet coaching on protein intake. A secondary objective examined its effects on muscle health. Participants included 53 women, age 45–64 years. All participants received NE and PRx; those randomized to coached-group received 10-weeks of diet coaching. Assessments included: protein intake at baseline, weeks 4 and 12 and muscle health (muscle mass, grip strength, five-chair rise test, 4 mgait speed test). The Chi-square test examined percentages of participants meeting PRx between groups. Repeated measures analysis of variance assessed within group and intervention effects on protein intake and muscle health parameters. Protein intake (g/kg body weight) increased (p < 0.001): not-coached (n = 28) 0.8 ± 0.2 to 1.2 ± 0.3 and coached (n = 25) 1.0 ± 0.2 to 1.4 ± 0.3 with no significant difference between groups. A greater percentage of coached-group participants met (p = 0.04) breakfast (72%) and met (p < 0.001) three-meal (76%) PRx versus not-coached participants (25% and 53%, respectively). Participants in both groups exhibited significantly (p < 0.001) improved times for the five-chair rise test and 4 mgait speed test. Diet coaching in conjunction with a PRx and NE should be considered to assist individuals in improving protein intake through self-selection of protein-rich foods.

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Impact of dietary protein intake and obesity on lean mass in middle-aged individuals after a 12-year follow-up: the Korean Genome and Epidemiology Study (KoGES)

British Journal Of Nutrition ◽

10.1017/s000711451900117x ◽

2019 ◽

Vol 122 (03) ◽

pp. 322-330 ◽

Cited By ~ 3

Author(s):

Eunjin So ◽

Seul Ki Choi ◽

Hyojee Joung

Keyword(s):

Lean Mass ◽

Dietary Protein ◽

Protein Intake ◽

Normal Weight ◽

Obese Group ◽

Dietary Protein Intake ◽

Epidemiology Study ◽

Obesity Status ◽

The Impact

AbstractThe present study investigated the association between protein intake and lean mass according to obesity status over a 12-year period. Data on 4412 participants aged 40–69 years were obtained from the Korean Genome and Epidemiology Study. The usual dietary protein intake of these participants was assessed at baseline using a semi-quantitative FFQ. Body composition was measured using bioelectrical impedance analysis at baseline and after a 12-year follow-up. Linear mixed-effects models were used to examine the associations between lean mass after a 12-year follow-up and protein intake at baseline. After adjusting for covariates and lean mass at baseline, comparisons between the highest and lowest tertiles revealed that dietary protein intake was positively associated with lean mass in both men (β = 0·79, P = 0·001) and women (β = 0·28, P = 0·082) after the 12-year period; however, those differences were attenuated after additional adjustment for fat mass at baseline and were stronger in the normal-weight group (men, β = 0·85, P = 0·002; women, β = 0·97, P < 0·001) but were not detected in the obese group. In the obese group, age (men, β = 4·08, P < 0·001; women, β = 2·61, P < 0·001) and regular physical activity (men, β = 0·88, P = 0·054; women, β = 0·76, P < 0·001) were significantly associated with lean mass after 12 years of follow-up. The results of the present study showed that protein intake may contribute to the prevention of ageing-related lean mass loss; however, the impact of this intake may vary depending on obesity status. Therefore, the maintenance of a healthy body weight during ageing through enhanced protein intake is likely to confer health benefits.

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The Impact of Varying Dietary Protein on Serum IGF-I, IGFBP-1, and IGFBP-3 during 6 Days of Physical Activity

International Journal of Sport Nutrition and Exercise Metabolism ◽

10.1123/ijsnem.17.2.127 ◽

2007 ◽

Vol 17 (2) ◽

pp. 127-139 ◽

Cited By ~ 2

Author(s):

Michael J. Ormsbee ◽

Jeffrey A. Clapper ◽

Joan L. Clapper ◽

Matthew D. Vukovich

Keyword(s):

Physical Activity ◽

Nitrogen Balance ◽

Dietary Protein ◽

Protein Intake ◽

Treadmill Running ◽

Serum Concentrations ◽

Post Intervention ◽

Igf I ◽

The Impact ◽

Igfbp 3

This study was designed to investigate the impact of dietary protein intake on serum concentrations of IGF-I and IGFBP-1 and relative amounts of serum IGFBP-3 during 6 d of physical activity. Ten men (23.8 ± 2.0 y of age) were assigned to 1 of 3 trials in a random crossover design. Each trial was isocaloric but with varying amounts of dietary protein: 50 g, 100 g, or 200 g. Subjects expended 500 kcal through treadmill running or weightlifting on alternate days for 6 d. Fasting blood samples were obtained for measurement of IGF-I, IGFBP-1, and IGFBP-3. Pre–post 24-h urine was measured for urea nitrogen. 50 g/d of protein resulted in a negative nitrogen balance, whereas 100 g/d and 200 g/d resulted in a positive nitrogen balance—200 g greater (P < 0.05) than 50 g and 100 g. Baseline IGF-I, BP-1, and BP-3 were not different among treatments. IGF-I decreased (P = 0.002) during the 6 d. Post intervention IGFBP-I was greater (P = 0.03) than at baseline. Post intervention IGFBP-3 values were not different from baseline or between trials. A 6-d modification of protein intake, while in energy balance, during a strength and conditioning program does not appear to modify serum concentrations of IGF-I or IGFBP-1 or relative amounts of IGFBP-3.

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The impact of dietary protein intake on serum biochemical and haematological profiles in vervet monkeys

Journal of Medical Primatology ◽

10.1111/j.1600-0684.2001.300108.x ◽

2001 ◽

Vol 30 (1) ◽

pp. 61-69 ◽

Cited By ~ 9

Author(s):

Q. Johnson ◽

W.J. Veith ◽

T. Mouton

Keyword(s):

Dietary Protein ◽

Protein Intake ◽

Vervet Monkeys ◽

Dietary Protein Intake ◽

Serum Biochemical ◽

The Impact

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Daily mycoprotein consumption for 1 week does not affect insulin sensitivity or glycaemic control but modulates the plasma lipidome in healthy adults: a randomised controlled trial

British Journal Of Nutrition ◽

10.1017/s0007114520002524 ◽

2020 ◽

Vol 125 (2) ◽

pp. 147-160

Author(s):

Mariana O. C. Coelho ◽

Alistair J. Monteyne ◽

Marlou L. Dirks ◽

Tim J. A. Finnigan ◽

Francis B. Stephens ◽

...

Keyword(s):

Blood Glucose ◽

Insulin Sensitivity ◽

Glycaemic Control ◽

Healthy Adults ◽

Blood Glucose Monitoring ◽

Whole Body ◽

Control Group ◽

Oral Glucose ◽

Post Intervention ◽

The Impact

AbstractMycoprotein consumption has been shown to improve acute postprandial glycaemic control and decrease circulating cholesterol concentrations. We investigated the impact of incorporating mycoprotein into the diet on insulin sensitivity (IS), glycaemic control and plasma lipoprotein composition. Twenty healthy adults participated in a randomised, parallel-group trial in which they consumed a 7 d fully controlled diet where lunch and dinner contained either meat/fish (control group, CON) or mycoprotein (MYC) as the primary source of dietary protein. Oral glucose tolerance tests were performed pre- and post-intervention, and 24 h continuous blood glucose monitoring was applied throughout. Fasting plasma samples were obtained pre- and post-intervention and were analysed using quantitative, targeted NMR-based metabonomics. There were no changes within or between groups in blood glucose or serum insulin responses, nor in IS or 24 h glycaemic profiles. No differences between groups were found for 171 of the 224 metabonomic targets. Forty-five lipid concentrations of different lipoprotein fractions (VLDL, LDL, intermediate-density lipoprotein and HDL) remained unchanged in CON but showed a coordinated decrease (7–27 %; all P < 0·05) in MYC. Total plasma cholesterol, free cholesterol, LDL-cholesterol, HDL2-cholesterol, DHA and n-3 fatty acids decreased to a larger degree in MYC (14–19 %) compared with CON (3–11 %; P < 0·05). Substituting meat/fish for mycoprotein twice daily for 1 week did not modulate whole-body IS or glycaemic control but resulted in changes to plasma lipid composition, the latter primarily consisting of a coordinated reduction in circulating cholesterol-containing lipoproteins.

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