Reconstructing the childhood diet of individuals buried with the Pictish monastic community at Portmahomack

This research aims to reconstruct the childhood diets (aged 9–10 years) of the individuals buried during the active years of the Pictish monastic community (hereafter referred to as PMC) from early medieval (7th–11th century) Portmahomack in north-east Scotland, using 13C and 15N isotopes. Dietary reconstructions were achieved by isotope analysis of δ13C and δ15N on the tooth root apex from permanent first molars (M1) of 26 adult male individuals. The results indicate that the indi-viduals in PMC predominantly consumed terrestrial C3 resources during childhood, with a rich terrestrial protein diet and some marine resource consumption. Statistically significant differences were observed between childhood and adulthood diets (the latter derived from previous research), suggesting that when these individuals were children, they consumed more marine protein than in later years as adults. This is true for all individuals, whether or not they spent significant time in Portmahomack during their childhoods. This is the most extensive study of the childhood diet of in-dividuals from the PMC and so makes a significant contribution to augmenting information on diet and lifestyles in Pictish Scotland.

Post-prandial Amino Acid Changes in Gilthead Sea Bream

Following a meal, a series of physiological changes occurs in fish as they digest, absorb and assimilate ingested nutrients. This study aims to assess post-prandial free amino acid (FAA) activity in gilthead sea bream consuming a partial marine protein (fishmeal) replacement. Sea bream were fed diets where 16 and 27% of the fishmeal protein was replaced by plant protein. The essential amino acid (EAA) composition of the white muscle, liver and gut of sea bream was strongly correlated with the EAA composition of the 16% protein replacement diet compared to the 27% protein replacement diet. The mean FAA concentration in the white muscle and liver changed at 4 to 8 h after a meal and was not different to pre-feeding (0 h) and at 24 h after feeding. It was confirmed in this study that 16% replacement of marine protein with plant protein meets the amino acid needs of sea bream. Overall, the present study contributes towards understanding post-prandial amino acid profiles during uptake, tissue assimilation and immediate metabolic processing of amino acids in sea bream consuming a partial marine protein replacement. This study suggests the need to further investigate the magnitude of the post-prandial tissue-specific amino acid activity in relation to species-specific abilities to regulate metabolism due to dietary nutrient utilization.

Torula Yeast in the Diet of Atlantic Salmon Salmo Salar and the Impact on Growth Performance and Gut Microbiome.

BackgroundLarge scale Atlantic salmon (Salmo salar) aquaculture is expanding, and with it, the need to find suitable replacements of conventional protein sources used in formulated feeds. Torula yeast (Cyberlindnera jadinii) has been identified as a promising alternative protein for aquaculture feeds, and can be sustainable cultivated from lignocellulosic biomasses, contributing to circular economic growth. The present study aimed to investigate the impact of torula yeast on the growth performance and the gut microbiome of freshwater Atlantic salmon to facilitate the commercial uptake of this alternative protein. Two types of diets were assessed in this study. Firstly, a marine protein base diet where fish meal (FM) was replaced with increasing inclusion levels of torula yeast, (0%, 10%, 20%) to provide a simplified replacement. Secondly, a marine protein and plant protein combination where mixed plant meals (MIX) were replaced with increasing inclusion levels of torula yeast, (0%, 10%, 20%) to provide a commercial relevant dietary replacement.ResultsThis study demonstrated that 20% torula yeast can replace fish meal without alteration to the growth performance while leading to potential benefits for the gut microbiome by increasing the presence of bacteria positively associated with the host. However, when torula yeast replaced a mix of plant meal in a combined protein source diet results suggest 10% inclusion of yeast produced the best growth performance results compared with both the control and 20% inclusion. At the highest inclusion level for the mixed diets potentially negative changes were observed in the gut microbial community, such as a decrease in lactic acid bacteria and an increased level of bacteria associated with slower growth in other salmonid species.ConclusionsThis study supports the application of torula yeast in the diet of Atlantic salmon as a partial replacement for conventional protein sources. However, the other components of the diet will need to be considered to determine the optimal inclusion level for this alternative protein. Future research should further optimise the inclusion of torula yeast in salmonid diets and investigate its influence on the functional role of the fish gut microbiome to facilitate improved formulated feed formulations and ensure a sustainable development of the aquaculture industry.

Limited Benefit of Marine Protein Hydrolysate on Physical Function and Strength in Older Adults: A Randomized Controlled Trial

Age-related muscle wasting can compromise functional abilities of the elderly. Protein intake stimulates muscle protein synthesis; however, ageing muscle is more resistant to stimuli. This double-blinded, randomized, controlled trial is one of the first registered studies to evaluate the effects of a supplement of marine protein hydrolysate (MPH) on measures of physical function and strength. Eighty-six older adults received nutritional supplements containing 3 g of MPH or a placebo for up to 12 months. Short Physical Performance Battery (SPPB), grip strength and gait speed were measured, and dietary intake was registered at baseline, 6 months, and 12 months. No difference was found between the intervention and control groups in mean change in SPPB (independent sample t-test, p = 0.41) or regarding time trend in SPPB, grip strength, or gait speed (linear mixed model). The participants in our study were well functioning, causing a ceiling effect in SPPB. Further, they had sufficient protein intake and were physically active. Differences in physical function between those completing the intervention and the dropouts might also have created bias in the results. We recommend that future studies of MPH be carried out on a more frail or malnourished population.

A dietary assessment of colonial Cape Town’s enslaved population

There is a growing body of bioarchaeological research on eighteenth and nineteenth century colonial Cape Town, a significant node in the transportation networks of both the Indian and Atlantic oceanic slave trades, attempting to shed light on the lives of enslaved persons. Here, a preliminary archaeological isotopic dietary baseline for the colonial Cape is presented. It is apparent from the data that cattle tended to graze far inland from Cape Town in an arid C3-C4 to purely C4 biome. Sheep/goats grazed close to the settlement or some distance away in C3 to C3-C4 biomes. A qualitative comparison of the baseline data to that of enslaved persons at The Cape suggests that this population did not consume large amounts of marine protein as has been concluded in the past. The archaeological baseline data was utilised, in combination with published modern data, to create a quantitative dietary reconstruction of a subset of this population using a Bayesian multi-source diet mixing model (FRUITS). The reconstruction confirms that the Cape’s enslaved did not consume much marine protein but relied predominantly on terrestrial C3 plant protein.

Correction to: The effect of low dose marine protein hydrolysates on short-term recovery after high intensity performance cycling: a double-blinded crossover study

The original article [1] contains errors in Tables 1 and 3: Table 1 erroneously mentions use of a treadmill which should instead state ‘bicycle’, and Table 3 has a minor typesetting mistake.

The effect of low dose marine protein hydrolysates on short-term recovery after high intensity performance cycling: a double-blinded crossover study

Background Knowledge of the effect of marine protein hydrolysate (MPH) supplementation to promote recovery after high intensity performance training is scarce. The aim of this study was to examine the effect of MPH supplementation to whey protein (WP) and carbohydrate (CHO): (CHO-WP-MPH), on short-term recovery following high intensity performance, compared to an isoenergetic and isonitrogenous supplement of WP and CHO: (CHO-WP), in male cyclists. Methods This was a double-blinded crossover study divided into three phases. Fourteen healthy men participated. In phase I, an incremental bicycle exercise test was performed for establishment of intensities used in phase II and III. In phase II (9–16 days after phase 1), the participants performed first one high intensity performance cycling session, followed by nutrition supplementation (CHO-WP-MPH or CHO-WP) and 4 hours of recovery, before a subsequent high intensity performance cycling session. Phase III (1 week after phase II), was similar to phase II except for the nutrition supplementation, where the participants received the opposite supplementation compared to phase II. Primary outcome was difference in time to exhaustion between the cycling sessions, after nutrition supplementations containing MPH or without MPH. Secondary outcomes were differences in heart rate (HR), respiratory exchange ratio (RER), blood lactate concentration and glucose. Results The mean age of the participants was 45.6 years (range 40–58). The maximal oxygen uptake (mean ± SD) measured at baseline was 54.7 ± 4.1 ml∙min− 1∙kg− 1. There were no significant differences between the two nutrition supplementations measured by time to exhaustion at the cycling sessions (meandiff = 0.85 min, p = 0.156, 95% confidence interval (CI), − 0.37, 2.06), HR (meandiff = 0.8 beats pr.min, p = 0.331, 95% CI, − 0.9, 2.5), RER (meandiff = − 0.05, p = 0.361, 95% CI -0.07 – 0.17), blood lactate concentration (meandiff = − 0.24, p = 0.511, 95% CI, − 1.00, 0.53) and glucose (meandiff = 0.23, p = 0.094, 95% CI, − 0.05, 0.51). Conclusions A protein supplement with MPH showed no effects on short-term recovery in middle-aged healthy male cyclists compared to a protein supplement without MPH. Trial registration The study was registered 02.05.2017 at ClinicalTrials.gov (Protein Supplements to Cyclists, NCT03136133, https://clinicaltrials.gov/ct2/show/NCT03136133?cond=marine+peptides&rank=1.

Establishment of a Greek Food Database for Palaeodiet Reconstruction: Case Study of Human and Fauna Remains from Neolithic to Late Bronze Age from Greece

We review the stable isotopic data of recovered Greek bones from the Early Neolithic to the Late Bronze period in order to examine dietary changes over time. As an isotopic baseline we use the published fauna data of the periods. The analysis revealed a diet that included a significant proportion of foods based on C3 plants, and the bulk of the animal protein must have been provided by terrestrial mammals with a small but detectable proportion of marine protein for coastal and island populations. A more significant contribution of marine protein is observed for Bronze Age populations while the enrichment in both C and N isotopes is connected, for some areas, to the introduction of millet during the Bronze Age, and to freshwater consumption. An extensive database of Greek food sources is presented and compared to the fauna from the prehistoric periods (Early Neolithic to Late Bronze Age) of the literature. We propose that this database can be used in palaeodiet reconstruction studies.

Nutrition and physical performance in older people—effects of marine protein hydrolysates to prevent decline in physical performance: a randomised controlled trial protocol

IntroductionAge-related loss of muscle mass, muscle strength and muscle function (sarcopenia) leads to a decline in physical performance, loss of independence and reduced quality of life. Nutritional supplements may delay the progression of sarcopenia. The aim of this randomised, double-blinded controlled trial including 100 participants (≥65 years) is to assess the effect of a marine protein hydrolysate (MPH) on sarcopenia-related outcomes like hand grip strength, physical performance or gait speed and to study the associations between physical performance and nutritional intake and status.Method and analysisThe intervention group (n=50) will receive 3 g of MPH per day in 12 months. The control group (n=50) receive placebo. Assessments of Short Physical Performance Battery (SPPB), hand grip strength, anthropometric measurements, nutritional status as measured by the Mini Nutritional Assessment, dietary intake, supplement use, biomarkers of protein nutrition and vitamin D, and health-related quality of life (EQ-5D), will be performed at baseline and after 6 and 12 months of intervention. Linear mixed models will be estimated to assess the effect of MPH on SPPB, hand grip strength and quality of life, as well as associations between physical performance and nutrition.Ethics and disseminationThe study has been approved by the Regional Committee in Ethics in Medical Research in Mid-Norway in September 2016 with the registration ID 2016/1152. The results will be actively disseminated through peer-reviewed journals, conference presentations, social media, broadcast media and print media.Trial registration numberNCT02890290.