Signs of malnutrition and starvation—Reconstruction of nutritional life histories by serial isotopic analyses of hair

Bone of contention: Intra-element variability in remodelling of human femora based on histomorphometric and isotope analyses

The volume of human carbon (δ13C) and nitrogen (δ15N) isotope data produced in archaeological research has increased markedly in recent years. However, knowledge of bone remodelling, its impact on isotope variation, and the temporal resolution of isotope data remains poorly understood. Varied remodelling rates mean different elements (e.g., femur and rib) produce different temporal signals but little research has examined intra-element variability. This study investigates human bone remodelling using osteon population density and the relationship with carbon and nitrogen isotope data at a high resolution, focusing on variation through femoral cross-sections, from periosteal to endosteal surfaces. Results demonstrate considerable differences in isotope values between cross-sectional segments of a single fragment, by up to 1.3‰ for carbon and 1.8‰ for nitrogen, illustrating the need for standardised sampling strategies. Remodelling also varies between bone sections, occurring predominantly within the endosteal portion, followed by the midcortical and periosteal. Therefore, the endosteal portion likely reflects a shorter period of life closer to the time of death, consistent with expectations. By contrast, the periosteal surface provides a longer average, though there were exceptions to this. Results revealed a weak negative correlation between osteon population density and δ15N or δ13C, confirming that remodelling has an effect on isotope values but is not the principal driver. However, a consistent elevation of δ15N and δ13C (0.5‰ average) was found between the endosteal and periosteal regions, which requires further investigation. These findings suggest that, with further research, there is potential for single bone fragments to reconstruct in-life dietary change and mobility, thus reducing destructive sampling.

Carbon, nitrogen, and sulfur elemental and isotopic variations in mouse hair and bone collagen during short-term graded calorie restriction

This study characterized the effect of calorie restriction (CR) on elemental content and stable isotope ratio measurements of bone "collagen" and hair keratin. Adult mice on graded CR (10-40%; 84 days) showed decreased hair δ 15N, δ 13C, and δ 34S values (significantly for δ 15N) with increasing CR, alongside a significant increase in bone "collagen" δ 15N values and a decrease in "collagen" δ 13C values. We propose this was likely due to the intensified mobilization of endogenous proteins, as well as lipids in newly synthesized "collagen". Elemental analysis of bone "collagen" revealed decreased carbon, nitrogen, and sulfur % content with increasing CR which is attributed to a change in the in vivo bone "collagen" structure with extent of CR. This complexity challenges the use of elemental indicators in the assessment of collagen quality in archaeological studies where nutritional stress may be a factor.

Diets, stress, and disease in the Etruscan society: Isotope analysis and infantile skeletal palaeopathology from Pontecagnano (Campania, southern Italy, 730-580 BCE)

Susceptibility to morbidity and mortality is increased in early life, yet proactive measures, such as breastfeeding and weaning practices, can be taken through specific investments from parents and wider society. The extent to which such biosocialcultural investment was achieved within 1st millennium BCE Etruscan society, of whom little written sources are available, is unkown. This research investigates life histories in non-adults and adults from Pontecagnano (southern Italy, 730-580 BCE) in order to track cross-sectional and longitudinal breastfeeding and weaning patterns and to characterize the diet more broadly. Stable carbon and nitrogen isotope analysis of incrementally-sampled deciduous and permanent dentine (n = 15), bulk bone collagen (n = 38), and tooth enamel bioapatite (n = 21) reveal the diet was largely based on C3 staple crops with marginal contributions of animal protein. Millet was found to play a role for maternal diet and trajectories of breastfeeding and feeding for some infants and children at the site. The combination of multiple isotope systems and tissues demonstrates exclusive breastfeeding was pursued until 0.6 years, followed by progressive introduction of proteanocius supplementary foods during weaning that lasted between approximately 0.7 and 2.6 years. The combination of biochemical data with macroscopic skeletal lesions of infantile metabolic diseases and physiological stress markers showed high δ15Ndentine in the months prior to death consistent with the isotopic pattern of opposing covariance.

Changes in urinary stable nitrogen isotope ratios during controlled short-term energy deficit: a proof-of-principle analysis

PURPOSE

Stable isotope ratios of nitrogen (δ15N) have previously been shown to increase in human hair during periods of catabolism. The goal of this study was to assess changes in δ15N in urinary urea (δ15Nurea) and Δ15N during a short-term controlled energy deficit.

METHODS

We analyzed samples from 6 recreationally active men (25 ± 1 years, BMI: 23.5 ± 0.6 kg/m2) who participated in a repeated measures cross-over study involving 4 days of energy deficit (ED, ~ 15 kcal/kg FFM) without and with exercise (ED-EX, ED + EX) and control conditions in energy balance (CON-EX, CON + EX). δ15Nurea was analyzed from urine samples, and Δ15N was calculated as δ15Nurea-δ15Ndiet, with δ15Ndiet obtained from diet prescriptions.

RESULTS

δ15Nurea was significantly elevated in ED-EX (4.4 ± 0.2‰) when compared to CON-EX (3.7 ± 0.1‰; p = 0.026) and CON + EX (3.34 ± 0.13‰, p = 0.001). As a consequence, Δ15N was positive in ED-EX (0.2 ± 0.2‰) and remained negative in ED + EX (- 0.6 ± 0.5‰), CON-EX (- 1.0 ± 0.2) and CON + EX (- 1.1 ± 0.2). Differences in Δ15N were significant between ED-EX and CON-EX (p = 0.005) and ED-EX and CON + EX (p = 0.006).

CONCLUSION

Our results suggest that δ15Nurea and subsequently Δ15N are responsive to a short-term energy deficit, likely due to increased amino acid oxidation to meet energy demands and preferable elimination of 14N.

Discerning animal-sourced food in diet using isotope analysis of human scalp hair and fingernails

PURPOSE

Diet-related diseases are advancing as the leading cause of death globally. As self-reporting of diet by patients can be associated with errors, stable isotopes of human tissues can be used to diagnose diseases, understand physiology, and detect change in diet. This study investigates the effect of type and amount of food on the nitrogen and carbon concentration (Nconc and Cconc) and isotopic composition (δ15N and δ13C) in human scalp hair and fingernails.

METHODS

A total of 100 residents participated in the study whereas only 74 individuals provided complete diet history. Sixty-six food items majorly available to them were also collected. The Nconc, Cconc, δ15N and δ13C values of human hair, nails and food items were determined.

RESULTS

The Nconc, Cconc, δ15N and δ13C values between plant-sourced and animal-sourced food items, as well as human hair and nail tissue were significantly different (p < 0.05). The δ15N value of human tissues was distinct between lacto-vegetarians and omnivores by 0.9‰. The δ15N and δ13C values of human tissues increased by 0.4-0.5‰ with every 5% increase in the consumption of animal protein.

CONCLUSIONS

The study helps to demarcate lacto-vegetarians from omnivores, and estimate the percentage of animal protein in diet based on the dual isotope values of human tissues. It also acts as a reference to determine isotopic composition of hair tissue provided the isotope value of nail tissue is known and vice versa.

Linear hair growth rates in preschool children

BACKGROUND

Human scalp hair is a validated bio-substrate for monitoring various exposures in childhood including contextual stressors, environmental toxins, prescription or non-prescription drugs. Linear hair growth rates (HGR) are required to accurately interpret hair biomarker concentrations.

METHODS

We measured HGR in a prospective cohort of preschool children (N = 266) aged 9-72 months and assessed demographic factors, anthropometrics, and hair protein content (HPC). We examined HGR differences by age, sex, race, height, hair pigment, and season, and used univariable and multivariable linear regression models to identify HGR-related factors.

RESULTS

Infants below 1 year (288 ± 61 μm/day) had slower HGR than children aged 2-5 years (p = 0.0073). Dark-haired children (352 ± 52 μm/day) had higher HGR than light-haired children (325 ± 50 μm/day; p = 0.0019). Asian subjects had the highest HGR overall (p = 0.016). Younger children had higher HPC (p = 0.0014) and their HPC-adjusted HGRs were slower than older children (p = 0.0073). Age, height, hair pigmentation, and HPC were related to HGR in multivariable regression models.

CONCLUSIONS

We identified age, height, hair pigment, and hair protein concentration as significant determinants of linear HGRs. These findings help explain the known hair biomarker differences between children and adults and aid accurate interpretation of hair biomarker results in preschool children.

IMPACT

Discovery of hair biomarkers in the past few decades has transformed scientific disciplines like toxicology, pharmacology, epidemiology, forensics, healthcare, and developmental psychology. Identifying determinants of hair growth in children is essential for accurate interpretation of hair biomarker results in pediatric clinical studies. Childhood hair growth rates define the time-periods of biomarker incorporation into growing hair, essential for interpreting the biomarkers associated with environmental exposures and the mind-brain-body connectome. Our study describes age-, sex-, and height-based distributions of linear hair growth rates and provides determinants of linear hair growth rates in a large population of children. Age, height, hair pigmentation, and hair protein content are determinants of hair growth rates and should be accounted for in child hair biomarkers studies. Our findings on hair protein content and linear hair growth rates may provide physiological explanations for differences in hair growth rates and biomarkers in preschool children as compared to adults.

Stable Isotopes Unveil Dietary Trends in the Samnite and Peligni Communities of Opi Val Fondillo and Sulmona S. Lucia (V-VI Centuries BCE, Abruzzo, Central Italy)

The purpose of this study is to gain insights into the subsistence activities and nutrition of the Samnite and Peligni populations who lived in the Abruzzo region (Italy) during the Iron Age. The samples under investigation are from Opi Val Fondillo (AQ) and Sulmona S. Lucia (AQ), dating between the Vth and VIth centuries BCE. Carbon and nitrogen isotopes were utilized to characterize the diet of the inhabitants in this region. The study involved analyzing carbon and nitrogen stable isotopes in 84 available samples and comparing them with isotopic values from animals found in the nearby sites of Loreto Aprutino, Gabii, and La Sassa's Cave. The results of this study revealed statistically significant differences between sexes in δ15N values. Additionally, significant statistical variations were observed when comparing different populations.

Tracking the British agricultural revolution through the isotopic analysis of dated parchment

Between the sixteenth and nineteenth century, British agriculture underwent a 'revolutionary' transformation. Yet despite over a century of research and the recognised centrality of agricultural developments to industrialisation and population growth, the character or chronology of any 'revolution' during this period remains contentious. Enquiry has been hampered by the fragmented and locally specific nature of historic accounts and the broad dating of early-modern zooarchaeological assemblages. To address this, we conducted stable isotope analysis on 658 legal documents written on sheepskin parchment; a unique biological resource that records the day, month and year of use (AD 1499 to 1969). We find these provide a high temporal resolution analysis of changing agricultural practices and episodes of disease. Most significantly, they suggest that if an 'Agricultural Revolution' occurred in livestock management, it did so from the mid-nineteenth century, in the aftermath of the Napoleonic Wars.

Holiday trip to Norway - a stable isotope project on hair strands of individuals of a travel group from Bavaria

Hair strands were taken from individuals of a travel group from Bavaria that stayed on the Lofoten Islands/Norway for 3 weeks. By means of serial stable isotope analyses of carbon, nitrogen, sulphur and hydrogen along the hair strands, food-specific changes during travel could be detected. The higher consumption of marine fish led to significant changes of the stable isotope values of nitrogen, sulphur and hydrogen. The highest differences for the values were found in the most proximal part of hair strands which were taken shortly after the trip. The basic values for the isotope distribution of the elements in the hair also indicate specific diets of some individuals that could be confirmed upon request.

Reproductive life histories: can incremental dentine isotope analysis identify pubertal growth, pregnancy and lactation?

BACKGROUND

There are few reliable osteological indicators to detect parity or infer puberty in skeletal remains. Nitrogen (δ¹⁵N) and stable carbon (δ¹³C) isotope ratios in human tissues can be affected by metabolically unbalanced states engendered by pregnancy or rapid growth, offering potential biomarkers.

AIM

This pilot study explores the potential of incremental dentine-collagen isotope ratio analysis to identify puberty and gestation.

SUBJECTS AND METHODS

Incremental dentine δ¹⁵N and δ¹³C profiles were produced by analysing third molars extracted as part of dental treatment of 10 individuals living in Sudan. Demographic and anthropometric data at the time of tooth extraction was available. Medical histories were unknown.

RESULTS

Isotopic signatures potentially related to pubertal growth, with an average δ¹⁵N reduction of 0.78 ± 0.29‰, are indicated. Six isotopic signals suggestive of pregnancy, with an average δ¹⁵N decrease of 0.48 ± 0.22‰, are also observed. The timing, speed and amplitude of post-partum δ¹⁵N patterns seemingly infer infant feeding practices and maternal nutritional status.

CONCLUSION

This pilot study highlights the potential of incremental dentine isotope analysis for the reconstruction of early reproductive histories in skeletal remains. However, controlled studies with a larger human cohort are needed to validate these findings, establish isotopic signals linked to puberty and lactation, and improve chronology accuracy.

Isotopic reconstruction of short to absent breastfeeding in a 19th century rural Dutch community

Artificial feeding of young infants is considered a modern phenomenon. However, historical sources note its practice in some past European populations. This research explores factors that contributed to a short to absent period of breastfeeding in pre-modern Netherlands. Stable nitrogen and carbon isotope analysis is undertaken on 277 19^th century individuals from Beemster, a, rural, mainly Protestant, dairy farming community. An intra-individual sampling approach for ≤6 year-olds compares newer metaphyseal to older diaphyseal long bone collagen to classify feeding status at death. Archivally identified individuals permit analyses of sex and year-of-death. Few infants have isotopic evidence for breastfeeding and, if present, it was likely of short duration or a minor source of dietary protein. From only a few weeks to months of age infants were fed cow’s milk and paps with sugar. There is broad dietary homogeneity with no sex or temporal isotopic differences, but young infants (1–11 months) have the most ẟ¹⁵N and ẟ¹³C variation highlighting the effect of multiple dietary and physiological processes. Beemster had many factors associated with high rates of breastfeeding in other Dutch communities, yet, most mothers did not breastfeed, or not for long, showing that regional variation in infant feeding is influenced by community values and traditions. On top of child rearing and domestic chores, female dairy farmers were in charge of milking cattle and dairy production, an important income source, suggesting high workload was also a factor in short or absent breastfeeding periods, aided by the constant supply of fresh milk that could be fed to an infant by an older sibling.

A comparison of dietary isotopes in pulp stones and incremental dentine from Early Neolithic individuals of the Whitwell Long Cairn, England

Objectives

This study investigates if palaeodietary information can be obtained from pulp stones through stable isotope analysis, presents a method for their extraction from tooth samples, and assesses their utility as a source of paleodietary information when coupled with the incremental dentine method.

Materials and Methods

Six tooth samples (2 per individual), four of which contained pulp stones, were selected from three Early Neolithic (3720–3650 cal BC) individuals from the Whitwell Long Cairn in Derbyshire, England. After demineralization, each tooth was divided into 1 mm increments. Stable isotope analysis of collagen was conducted on each dentine increment and a portion of each pulp stone.

Results

All samples met the quality control criteria for well‐preserved collagen. Excluding the pulp stones, the mean δ¹³C value of the teeth sampled was −21.5 ± 0.2‰ and the mean δ¹⁵N value was 9.9 ± 0.5‰, suggesting these individuals had a terrestrial‐based diet. The pulp stones produced similar δ¹³C values between −21.6 and −21.4‰ and δ¹⁵N values between 9.1 and 9.8‰.

Discussion

The results demonstrate that paleodietary information can be obtained from pulp stones through stable isotope analysis. There are, however, significant challenges in interpreting this data, particularly as to inferring the timing and duration of their formation. The pulp stone results were compared with the incremental dentine profiles for each person to further investigate when they might have formed. For two individuals, the pulp stones appear to reflect diet from a time period after childhood and adolescence. For the third individual, it could not be determined if the pulp stones reflect a contemporary or later time period than the incremental dentine series. All teeth with pulp stones have moderate to severe wear on the occlusal surface, which could have been a contributing factor to their development.

Longitudinal isotope ratio variations in human hair and nails

Due to the straightforward and non-invasive sampling, ease of transport and long-term storage and access to time-resolved information, determination of element concentrations and isotope ratios in hair and nails finds increasing use. Multi-isotopic information preserved in keratinous tissues allows one to reveal dietary, physiological and environmental influences, but progress in this area is still limited by complicated and time-consuming analytical procedures and challenges in accuracy assessment. In this study, longitudinal distributions of δ³⁴S, ⁸⁷Sr/⁸⁶Sr, ^207,208Pb/²⁰⁶Pb, δ⁶⁶Zn, δ⁵⁶Fe, δ⁶⁵Cu, δ²⁶Mg, and δ¹¹⁴Cd were obtained for hair and nails collected from nine subjects with different age, biological sex, diet and/or place of residence. For S and Zn, the distribution along hair strands revealed a trend towards a heavier isotopic signature from the proximal to the distal end, with a maximum difference within the hair of a single subject of 1.2‰ (Δ³⁴S) and 0.4‰ (Δ⁶⁶Zn). For Fe, Cu, Mg and Cd, a shift towards either a lighter (Cu) or heavier (Fe, Mg and Cd) isotopic composition is accompanied by increasing concentration towards the distal hair end, indicating possible isotope fractionation during deposition or external contamination with a different isotopic composition. Pb and Sr isotope ratios are relatively stable throughout the hair strands despite notable concentration increases towards the distal end, likely reflecting external contamination. The isotopic composition of Sr points to tap water as a probable main source, explaining the relative stability of the ratio for individuals from the same geographical location. For Pb, isotopic compositions suggest tap water and/or indoor dust as possible sources. Similar δ³⁴S, ⁸⁷Sr/⁸⁶Sr, ^207,208Pb/²⁰⁶Pb, δ⁶⁶Zn, δ⁵⁶Fe, and δ⁶⁵Cu observed for hair, fingernails and toenails sampled from the same individual suggest that keratinous tissues are conservative receivers of internal and external inputs and can be used complementary. Seasonal variation in δ³⁴S, ^207,208Pb/²⁰⁶Pb, and δ⁶⁵Cu was observed for fingernails.

Sidon on the breadth of the wild sea: Movement and diet on the Mediterranean coast in the Middle Bronze Age

OBJECTIVES

Excavations at Sidon (Lebanon) have revealed dual identities during the Middle Bronze Age (ca. 2000-1600 BCE): a maritime port and center for local distribution, as well as a settlement with a heavy subsistence dependence on the extensive inland hinterlands. We aim to investigate residential mobility at Sidon using isotopic analyses of 112 individuals from 83 burials (20 females, 26 males, and 37 subadults). Veneration and remembrance of the dead is evident from funerary offerings in and near the tombs. With marine fish a major component in funerary offerings, we predict major marine reliance in this coastal population.

MATERIALS AND METHODS

New isotopic evidence of paleomobility (⁸⁷ Sr/⁸⁶ Sr, δ¹⁸ O) and diet (δ¹³ C_carbonate ) is the focus of this research. Previous bulk bone collagen δ¹³ C and δ¹⁵ N analysis is strengthened by further sampling, along with δ³⁴ S where collagen yield was sufficient.

RESULTS

The five non-locals identified (8.9% of the 56 analyzed) come from constructed tombs with high-status grave goods except for one, which was heavily disturbed in antiquity. Dietary investigation of the population confirms reliance on terrestrial resources with no significant marine input. No significant differences in diet between the sexes or burial types are present.

CONCLUSIONS

Although Sidon was part of a growing Mediterranean network evidenced through artefactual finds, relatively low immigration is evident. While religious feasts venerating the dead may have involved significant piscine components, no appreciable marine input in diet is observed. Fish may have been reserved for the deceased or only consumed on feast days alongside the dead rather than a regular part of the Bronze Age menu.

A modern baseline for the paired isotopic analysis of skin and bone in terrestrial mammals

We present the isotopic discrimination between paired skin and bone collagen from animals of known life history, providing a modern baseline for the interpretation of archaeological isotopic data. At present, the interpretation of inter-tissue variation (Δ_(skin-bone)) in mummified remains is based on comparisons with other archaeological material, which have attributed divergence to their contrasting turnover rates, with rapidly remodelling skin collagen incorporating alterations in environmental, cultural and physiological conditions in the months prior to death. While plausible, the lack of baseline data from individuals with known life histories has hindered evaluation of the explanations presented. Our analysis of a range of animals raised under a variety of management practices showed a population-wide trend for skin collagen to be depleted in ¹³C by -0.7‰ and enriched in ¹⁵N by +1.0‰ relative to bone collagen, even in stillborn animals. These results are intriguing and difficult to explain using current knowledge; however, on the basis of the findings reported here, we caution any results which interpret simply on differing turnover rates. We hypothesize that there may be a consistent difference in the routing of dietary protein and lipids between skin and bone, with potentially on-site synthesis of non-essential amino acids using carbon and nitrogen that have been sourced via different biochemical pathways.

Children of the abyss: Investigating the association between isotopic physiological stress and skeletal pathology in London during the Industrial Revolution

OBJECTIVE

This project sought to investigate whether an association may be observed between isotopic stress indicators and skeletal evidence of pathological conditions.

MATERIALS

Deciduous and permanent teeth of 15 non-adults from two contemporaneous mid-19th century London burial grounds (City Bunhill, Lukin Street).

METHODS

δ¹³C and δ¹⁵N was measured in the incrementally sectioned dentine collagen. Isotopic profiles for each individual included death during tooth development.

RESULTS

Individuals with skeletal evidence of chronic pathological conditions (e.g., rickets, tuberculosis) exhibited raised δ¹⁵N values of 0.5-1.7‰ in the months prior to death. Isotopic change consistent with chronic physiological stress prior to death was also recorded in two individuals with no skeletal evidence of disease. An offset was observed between co-forming bone and dentine δ¹⁵N values in both populations, indicating that bone and dentine are not recording the same isotopic changes.

CONCLUSIONS

Isotopic change consistent with chronic physiological stress was observed in both those with and without skeletal evidence of disease, suggesting that adaptation to chronic stress in childhood was not uncommon within these 19th century London populations.

SIGNIFICANCE

Chronic physiological stress prior to death may be seen in the incrementally sampled dentine of non-adults who die during tooth formation.

LIMITATIONS

The temporal resolution of current dentine micro-sampling methods may mask or minimise visibility of shorter-term periods of stress or dietary change.

SUGGESTIONS FOR FURTHER RESEARCH

Future research should further explore the relationship between specific skeletal pathologies and isotopic evidence for stress.

Breastfeeding and weaning in Late Holocene hunter-gatherers of the lower Paraná wetland, South America

OBJECTIVE

In this study, we analyze breastfeeding and weaning practices in pre-Columbian complex hunter-gatherers from the lower Paraná River basin (South America).

MATERIALS AND METHODS

We carried out bone isotope analyses concerning δ¹³ C in collagen and apatite, the spacing between both carbon sources and δ¹⁵ N in a sample of 23 subadult and adult individuals of both sexes recovered from Late Holocene archaeological sites, ranging from 1665 ± 45 to 680 ± 80 ¹⁴ C years BP.

RESULTS AND DISCUSSION

The results indicate that exclusive breastfeeding continued until the age of ~2 years, and weaning probably until 4 years of age. Supplementary foods included C₃ plants and probably animal fats and C₄ carbohydrates. A high fractionation of 4.9‰ in δ¹⁵ N values was recognized between breastfeeding infants and adult females, perhaps reflecting episodic hyper-protein diets in women linked to men's food provisioning during women's gestational/postpartum period. Additionally, male adults present a higher protein intake than females. Although this difference is not statistically significant with the current sample size, it could be a clue related to a sexual division in food procurement.

Bronze Age innovations and impact on human diet: A multi-isotopic and multi-proxy study of western Switzerland

The archaeological Bronze Age record in Europe reveals unprecedented changes in subsistence strategies due to innovative farming techniques and new crop cultivation. Increasing cultural exchanges affected the economic system. The inhabitants of Switzerland played a pivotal role in this European context through relationships with the Mediterranean, the High and Middle Danube regions and the Alps thanks to the area’s central position. This research aims to reconstruct, for the first time in Switzerland, human socio-economic systems through the study of human diet, herding and farming practices and their changes throughout the Bronze Age (2200–800 BCE) by means of biochemical markers. The study includes 41 human, 22 terrestrial and aquatic animal specimens and 30 charred seeds and chaff samples from sites in western Switzerland. Stable isotope analyses were performed on cereal and legume seeds (δ¹³C, δ¹⁵N), animal bone collagen (δ¹³C_coll, δ¹⁵N, δ³⁴S), human bone and tooth dentine collagen (δ¹³C_coll, δ¹⁵N,) and human tooth enamel (δ¹³C_enamel). The isotopic data suggest a) an intensification of soil fertilization and no hydric stress throughout the Bronze Age, b) a human diet mainly composed of terrestrial resources despite the proximity of Lake Geneva and the Rhone river, c) a diet based on C₃ plants during the Early and Middle Bronze Age as opposed to the significant consumption of ¹³C-enriched resources (probably millet) by individuals from the Final Bronze Age, d) no important changes in dietary patterns throughout an individual’s lifespan but a more varied diet in childhood compared to adulthood, e) no differences in diet according to biological criteria (age, sex) or funerary behavior (burial architecture, grave goods).

The dietary behavior of two early medieval individuals with temporomandibular ankylosis

OBJECTIVES

This study aimed to reconstruct the dietary behavior of two early medieval individuals who display gnathic malformation.

MATERIAL

Two skeletons affected by temporomandibular ankylosis were analyzed, one from the Great Moravian burial site of Rajhradice (9th century AD, Czech Republic), and the other from the Avar burial site of Schӧnkirchen (8th century AD, Austria).

METHODS

Carbon and nitrogen isotopic values were measured from the bone collagen of both individuals. In the Rajhradice case, where the childhood origin of ankylosis is deduced, isotopic analysis of dentine sections was performed.

RESULTS

Both individuals show isotopic values within the range of variation of a contemporaneous population sample. There was no observable dietary change in the Rajhradice individual that could be linked to the occurrence of ankylosis.

CONCLUSIONS

Both individuals consumed diets typical for their populations. They appear to not have restricted access to foodstuffs, namely animal protein, which would likely have had to be served in liquid (e.g. milk) or in a highly mashed form to compensate for insufficient mastication.

SIGNIFICANCE

This finding provides specific evidence of care provided to these two afflicted members of past populations.

LIMITATIONS

Though the proportion of animal protein is an important indicator of the quality of diet, many other aspects of diet - such as micronutrient content - elude stable isotope analysis.

SUGGESTIONS FOR FURTHER RESEARCH

Amino acid compound specific isotope analyses of collagen would provide deeper insight into both the diet and physiology of the affected individuals.

Socioeconomic and geographic implications from carbon, nitrogen, and sulfur isotope ratios in human hair from Mexico

This article presents data on carbon (C), nitrogen (N), and sulfur (S) isotopic composition of human hair collected throughout Mexico. The recorded values ranged from -18.3‰ to -12.8‰ for δ¹³C, 6.8‰ to 10.8‰ for δ¹⁵N and from 2.7‰ to 8.0‰ for δ³⁴S. The socioeconomic covariates explored in this study showed, in part strong correlations with the recorded isotope values. Furthermore, these three isotope systems provide records of the dietary preferences and practices and also showed some spatial variation. This study detected geospatial patterning in the δ¹³C values of hair samples from Mexico as well as significant correlations with socioeconomic factors. No geospatial variation was detected in the δ¹⁵N and δ³⁴S values, however, socioeconomic correlations were found. A δ¹³C isoscape was generated using a GIS approach, which provides a tool to narrow down region-of-origin predictions (in combination with other isotope systems) and to document the travel history of unidentified individuals.

Splitting hairs: dietary niche breadth modelling using stable isotope analysis of a sequentially grown tissue

Stable isotope data from durable, sequentially grown tissues (e.g. hair, claw, and baleen) is commonly used for modelling dietary niche breadth. The use of tissues grown over multiple months to years, however, has the potential to complicate isotopic niche breadth modelling, as time-averaged stable isotope signals from whole tissues may obscure information available from chronologically resolved stable isotope signals in serially sectioned tissues. We determined if whole samples of brown bear guard hair produced different isotopic niche breadth estimates than those produced from subsampled, serially sectioned samples of the same tissue from the same set of individuals. We sampled guard hair from brown bears (Ursus arctos) in four regions of Alaska with disparate biogeographies and dietary resource availability. Whole hair and serially sectioned hair samples were used to produce paired isotopic dietary niche breadth estimates for each region in the SIBER Bayesian model framework in R. Isotopic data from serially sectioned hair consistently produced larger estimates of isotopic dietary niche breadth than isotope data from whole hair samples. Serial sampling captures finer-scale changes in diet and when cumulatively used to estimate isotopic niche breadth, the serially sampled isotope data more fully captures dietary variability and true isotopic niche breadth.

Prenatal effects of maternal nutritional stress and mental health on the fetal movement profile

Purpose

Prenatal sub-optimal nutrition and exposure to maternal stress, anxiety and depression in pregnancy have been linked to increased postnatal morbidity and mortality. Fetal growth is most vulnerable to maternal dietary deficiencies, such as those evident in hyperemesis gravidarum (HG), early in pregnancy. The purpose of this pilot study was to examine the effects of HG on fetal movement profiles as a measure of fetal healthy development in the 3rd trimester of pregnancy, and to assess whether nutritional stress on the mother can be evaluated using isotopic analysis of hair.

Method

We analyzed fetal movement profiles using 4D ultrasound scans at 32- and 36-weeks' gestation. Fetuses of women (N = 6) diagnosed with HG, having lost more than 10% of their body weight in the first trimester of pregnancy were compared to a healthy group (N = 6), controlling for stress, depression and anxiety. We tested carbon and nitrogen isotope ratios in maternal hair as a measure of both diet and nutritional changes due to catabolism of body proteins and fats.

Results

HG and catabolism were significantly correlated (p = 0.02). Furthermore, at 32-weeks' gestation movement profiles of fetuses of mothers with HG differed significantly from the movement profiles of fetuses of healthy mothers. Fetuses of mothers suffering from HG showed a significantly increased ratio of fine-grained movements at 32 weeks (p = 0.008); however, there were no significant differences detectable at 36-weeks' gestation.

Conclusion

The effect of HG on fetal development as expressed by variations in fetal movement profiles in this pilot study suggest that prenatal effects of HG can be measured using movement profiles. Isotope analysis of hair can supplement this with information on nutritional imbalances early in pregnancy.

Electronic supplementary material

The online version of this article (10.1007/s00404-020-05571-w) contains supplementary material, which is available to authorized users.

Buried in water, burdened by nature-Resilience carried the Iron Age people through Fimbulvinter

Levänluhta is a unique archaeological site with the remains of nearly a hundred Iron Age individuals found from a water burial in Ostrobothnia, Finland. The strongest climatic downturn of the Common Era, resembling the great Fimbulvinter in Norse mythology, hit these people during the 6th century AD. This study establishes chronological, dietary, and livelihood synthesis on this population based on stable carbon and nitrogen isotopic and radiocarbon analyses on human remains, supported by multidisciplinary evidence. Extraordinarily broad stable isotopic distribution is observed, indicating three subgroups with distinct dietary habits spanning four centuries. This emphasizes the versatile livelihoods practiced at this boundary of marine, freshwater, and terrestrial ecosystems. While the impact of the prolonged cold darkness of the 6th century was devastating for European communities relying on cultivation, the broad range of livelihoods provided resilience for the Levänluhta people to overcome the abrupt climatic decline.

Assessment of nutritional stress in famine burials using stable isotope analysis

OBJECTIVES

We compared δ¹⁵ N and δ¹³ C values from bone and dentine collagen profiles of individuals interred in famine-related and attritional burials to evaluate whether individuals in medieval London who experienced nutritional stress exhibit enriched nitrogen in bone and tooth tissue. Dentine profiles were evaluated to identify patterns that may be indicative of famine during childhood and were compared with the age of enamel hypoplasia (EH) formation to assess whether isotopic patterns of undernutrition coincide with the timing of physiological stress.

MATERIALS AND METHODS

δ¹⁵ N and δ¹³ C isotope ratios of bone collagen were obtained from individuals (n = 128) interred in attritional and famine burials from a medieval London cemetery (c. 1120-1539). Temporal sequences of δ¹⁵ N and δ¹³ C isotope profiles for incrementally forming dentine collagen were obtained from a subset of these individuals (n = 21).

RESULTS

Results indicate that individuals from attritional graves exhibit significantly higher δ¹⁵ N values but no significant differences were found between burial types for the sexes. Analyses of dentine profiles reveal that a lower proportion of famine burials exhibit stable dentine profiles and that several exhibit a pattern of opposing covariance between δ¹⁵ N and δ¹³ C. EH were also observed to have formed during or after the opposing covariance pattern for some individuals.

CONCLUSIONS

The results of this study may reflect differences in diet between burial types rather than nutritional stress. Though nutritional stress could not be definitively identified using bone and dentine collagen, the results from dentine analysis support previous observations of biochemical patterns associated with nutritional stress during childhood.

Reconstructing Bronze Age diets and farming strategies at the early Bronze Age sites of La Bastida and Gatas (southeast Iberia) using stable isotope analysis

The El Argar society of the Bronze Age in the southeast of the Iberian Peninsula (2200–1550 cal BCE) was among the first complex societies in Europe. Its economy was based on cereal cultivation and metallurgy, it was organized hierarchically, and successively expanded its territory. Most of the monumentally fortified settlements lay on steeply sloped mountains, separated by fertile plains, and allowed optimal control of the area. Here, we explore El Argar human diets, animal husbandry strategies, and food webs using stable carbon and nitrogen isotope analysis of charred cereal grains as well as human and animal bone collagen. The sample comprised 75 human individuals from the sites of La Bastida (n = 52) and Gatas (n = 23), 32 domesticated and wild animals as well as 76 barley and 29 wheat grains from two chronological phases of a total time span of ca. 650 years. The grains indicate extensive cereal cultivation under rain-fed conditions with little to moderate application of manure. Especially at La Bastida, crops and their by-products contributed significantly to the forage of the domesticated animals, which attests to a strong interrelation of cultivation and animal husbandry. Trophic level spacing and Bayesian modelling confirm that human diets were largely based on barley with some contribution of meat or dairy products. A cross-sectional analysis of bone collagen suggests that children were breastfed until about 1.5–2 years old, and infants from Gatas may have suffered from more metabolic stress than those at La Bastida. Adults of both sexes consumed similar diets that reflect social and chronological variation to some extent. Despite significantly higher δ¹³C and δ¹⁵N values at La Bastida than at Gatas, the isotopic data of the staple crops and domestic animals from both sites indicate that such differences do not necessarily correspond to different average human diets, but to agricultural strategies. These results urge for a reassessment of previous isotope studies in which only human remains have been taken into account. The study highlights that disentangling the complex influences on human isotope compositions requires a firm set of comparative data.

Raising girls and boys in early China: Stable isotope data reveal sex differences in weaning and childhood diets during the eastern Zhou era

Objectives

Using stable isotope analysis of incremental dentin segments, we reconstruct breastfeeding, weaning, and childhood dietary patterns of Eastern Zhou period (771–221 BC) individuals from the Central Plains of China. Previous isotopic research on the Eastern Zhou demonstrated dietary difference between male and female diets in adulthood via bone collagen analysis. To understand the development of gendered dietary patterns we must examine the early life period. We aim to identify the timing of the weaning process, whether childhood diets were the same as adulthood diets, and if there were differences between the diets of boys and girls during childhood.

Materials and Methods

We present incremental dentin and bone collagen δ¹³C and δ¹⁵N isotope data from 23 individuals from two Eastern Zhou archaeological sites (Xiyasi 西亚斯and Changxinyuan 畅馨苑).

Results

Weaning was completed between ages 2.5 and 4 years. Females were weaned slightly earlier than males. Early childhood diets show significant incorporation of C₃ foods, such as wheat and soybean, for almost all children, while later adulthood diets indicate greater incorporation of C₄ foods (millets), particularly for males.

Discussion

Childhood diets included greater amounts of C₃ foods than expected, suggesting that grains such as wheat may have been adopted in these communities as foods for children. Nevertheless, dietary differentiation between females and males began in childhood, with boys eating more millets (C₄ foods) than girls. The findings suggest that feeding children was a significant aspect of socialization and cultural gendering of individuals in ancient China.

Effect of different healing stages on stable isotope ratios in skeletal lesions

INTRODUCTION

Physiological stress is one of the various factors that can have an impact on stable isotope ratios. However, its effect on bone collagen stable isotope ratios is still not fully understood. This study aims to build on previous research on how different disease stages may affect bone collagen stable isotope ratios.

MATERIALS AND METHODS

Carbon (δ¹³ C) and nitrogen (δ¹⁵ N) isotope ratios were assessed in 33 skeletons that retained evidence of infectious disease and healed fractures. Samples were taken from active lesions (long bones n = 14; ribs n = 4), healed lesions (long bones n = 10; ribs n = 9), or a fracture callus (long bones n = 9; ribs n = 3). Results were compared to stable isotope ratios calculated for regions on these bones that did not retain evidence of disease or fracture.

RESULTS

Long bones with active lesions had a significantly higher average δ¹⁵ N (δ¹⁵ N = 11.1 ± 0.9‰) compared to those without lesions (δ¹⁵ N = 10.7 ± 0.7‰; p = .02), while fracture calluses showed the largest range for both δ¹⁵ N and δ¹³ C. There were no significant differences in stable isotope ratios when compared between nonlesion and lesion sites in the ribs.

DISCUSSION

The increase in δ¹⁵ N seen in active lesions, when compared with δ¹⁵ N from nonlesion regions on the same long bone, may be a consequence of altered protein metabolism. The high variability of δ¹⁵ N and δ¹³ C in fractures may be related to different healing stages of the calluses. This study suggests that stable isotope data can contribute information about diseases in the past, as well as an individual's response to diseases in the absence of modern medicine and antibiotics.

A new method for investigating the relationship between diet and mortality: hazard analysis using dietary isotopes

Background: The population of Roman Britain are renowned for having elevated nitrogen (δ¹⁵) stable isotope values, which have been interpreted as evidence for the increased consumption of marine products. However, such results are now understood to also reflect episodes of stress and disease, suggesting that new interpretations are warranted.Aim: To test a novel approach which combines hazard mortality analysis and stable isotope data to determine whether there is a relationship between age-at-death, elevated δ¹⁵N values and mortality risk.Subjects and methods: This study used published osteological and dietary stable isotope data for nitrogen (δ¹⁵N) and carbon (δ¹³C) of 659 1st-5th century AD individuals aged >12 years old excavated from Roman cemeteries in Britain. The relationship between diet and mortality risk was assessed using the Gompertz hazard model, and differences in median reported isotope values between the sexes was determined using a Mann Whitney test.Results: It was discovered that higher δ¹⁵N levels are associated with elevated risks of mortality, whereas the opposite pattern was observed for δ¹³C, and males had higher median δ¹³C and δ¹⁵N values.Conclusion: This study successfully demonstrated that stable isotope data can be integrated into hazard models, allowing one to connect diet and mortality in past populations. It supports the findings of other isotope studies which have established that individuals with childhood stress/trauma will have different isotope patterns.

The Skiles Mummy: Care of a debilitated hunter-gatherer evidenced by coprolite studies and stable isotopic analysis of hair

The Skiles Mummy (SMM), a naturally mummified adult male from the late archaic period of Lower Pecos Canyonlands of South Texas, represents a unique case of care. SMM is an exceptional mummy within this region due to both the retention of a full head of hair, and having a diagnosed case of megacolon, a complication commonly associated with Chagas disease caused by Trypanosoma cruzi. Stable isotopic analysis of his hair is consistent with a diet incorporating of C₄/CAM plants with some C₃ plants, freshwater resources, and higher trophic level animals. However, the segments of hair most proximal to the scalp exhibited elevated δ¹⁵N values. Data from previous research indicate starvation and malnutrition can cause δ¹⁵N values to rise. The presence of large fecal boluses in the digestive tract suggest peristalsis ceased in the last four to five months of life, and this, together with results from coprolite analysis, indicate he would not have been able to adequately absorb protein and nutrients during this time. His condition would have rendered him immobile. Following Tilley's index of care, someone would have had to bring him food resources, as well as attending to his daily needs.

Using evidence from hair and other soft tissues to infer the need for and receipt of health-related care provision

The Bioarchaeology of Care approach developed by Tilley is usually applied to skeletalized human remains, given the usual constraints of preservation bias that are seen with archaeological assemblages. However, other tissues, such as hair are sometimes preserved and can provide a wealth of information that can supplement the skeletal data. Archaeological hair has been analysed for drug compounds for almost thirty years. This article integrates data from hair analyses for coca metabolites, stable light isotope analysis and aDNA to expand the potential of the Bioarchaeology of Care approach using the example of a spontaneously mummified adult female from northern Chile.

An isotopic case study of individuals with syphilis from the pathological-anatomical reference collection of the national museum in Prague (Czech Republic, 19th century A.D.)

OBJECTIVE

This paper aims at investigating the possible existence of isotopic offsets in δ¹³C_col and δ¹⁵N_col values in relation to tertiary syphilis.

MATERIAL

Based on materials from the 19th c. A.D. deriving from the pathological-anatomical reference collection (the Jedlička collection) of the National Museum in Prague (Czech Republic), a comparative approach of ten individuals with syphilis and nine without the disease was undertaken.

METHODS

Bone powder samples were defatted according to the protocol of Liden et al. (1995). Bone collagen was extracted following the protocol of Bocherens et al. (1991).

RESULTS

Our results show that individuals with syphilis have lower δ¹³C_col values than individuals without the disease; the observed difference between the two groups is about 0.3-0.4‰, which is relatively small but still meaningful. However, no difference between δ¹⁵N_col values of the two groups has been noticed.

CONCLUSIONS

Either diets prescribed by physicians to syphilitic patients or nutritional stress caused by cyclic appetite disturbance due to the disease itself or the administered medical treatment appeared to be possible explanations of the observed isotopic pattern. Overall, the response of the two isotopic proxies could argue for relatively limited nutritional restrictions.

SIGNIFICANCE

This is the first study examining bone collagen isotopic response to syphilis based on clinically documented human skeletal materials.

LIMITATIONS

The sample sizes are relatively small and cautiousness must be taken regarding the interpretations of the data.

SUGGESTIONS FOR FURTHER RESEARCH

Compound-specific stable isotope investigations and analysis of mercury content could be helpful to better understand the observed isotopic effects.

The Importance of Isotopic Turnover for Understanding Key Aspects of Animal Ecology and Nutrition

Stable isotope-based methods have proved to be immensely valuable for ecological studies ranging in focus from animal movements to species interactions and community structure. Nevertheless, the use of these methods is dependent on assumptions about the incorporation and turnover of isotopes within animal tissues, which are oftentimes not explicitly acknowledged and vetted. Thus, the purpose of this review is to provide an overview of the estimation of stable isotope turnover rates in animals, and to highlight the importance of these estimates for ecological studies in terrestrial, freshwater, and marine systems that may use a wide range of stable isotopes. Specifically, we discuss 1) the factors that contribute to variation in turnover among individuals and across species, which influences the use of stable isotopes for diet reconstructions, 2) the differences in turnover among tissues that underlie so-called ‘isotopic clocks’, which are used to estimate the timing of dietary shifts, and 3) the use of turnover rates to estimate nutritional requirements and reconstruct histories of nutritional stress from tissue isotope signatures. As we discuss these topics, we highlight recent works that have effectively used estimates of turnover to design and execute informative ecological studies. Our concluding remarks suggest several steps that will improve our understanding of isotopic turnover and support its integration into a wider range of ecological studies.

Natural Isotope Abundances of Carbon and Nitrogen in Tissue Proteins and Amino Acids as Biomarkers of the Decreased Carbohydrate Oxidation and Increased Amino Acid Oxidation Induced by Caloric Restriction under a Maintained Protein Intake in Obese Rats

A growing body of evidence supports a role for tissue-to-diet ¹⁵N and ¹³C discrimination factors (Δ¹⁵N and Δ¹³C), as biomarkers of metabolic adaptations to nutritional stress, but the underlying mechanisms remain poorly understood. In obese rats fed ad libitum or subjected to gradual caloric restriction (CR), under a maintained protein intake, we measured Δ¹⁵N and Δ¹³C levels in tissue proteins and their constitutive amino acids (AA) and the expression of enzymes involved in the AA metabolism. CR was found to lower protein mass in the intestine, liver, heart and, to a lesser extent, some skeletal muscles. This was accompanied by Δ¹⁵N increases in urine and the protein of the liver and plasma, but Δ¹⁵N decreases in the proteins of the heart and the skeletal muscles, alongside Δ¹³C decreases in all tissue proteins. In Lys, Δ¹⁵N levels rose in the plasma, intestine, and some muscles, but fell in the heart, while in Ala, and to a lesser extent Glx and Asx, Δ¹³C levels fell in all these tissues. In the liver, CR was associated with an increase in the expression of genes involved in AA oxidation. During CR, the parallel rises of Δ¹⁵N in urine, liver, and plasma proteins reflected an increased AA catabolism occurring at the level of the liver metabolic branch point, while Δ¹⁵N decreases in cardiac and skeletal muscle proteins indicated increased protein and AA catabolism in these tissues. Thus, an increased protein and AA catabolism results in opposite Δ¹⁵N effects in splanchnic and muscular tissues. In addition, the Δ¹³C decrease in all tissue proteins, reflects a reduction in carbohydrate (CHO) oxidation and routing towards non-indispensable AA, to achieve fuel economy.

Evaluation of neodymium isotope analysis of human dental enamel as a provenance indicator using 1013 Ω amplifiers (TIMS)

Human provenance studies employing isotopic analysis have become an essential tool in forensic and archaeological sciences, with multi-isotope approaches providing more specific location estimates compared to single isotope studies. This study reports on the human provenancing capability of neodymium isotopes (¹⁴³Nd/¹⁴⁴Nd), a relatively conservative tracer in the environment. Neodymium isotope ratios have only recently been determined on human remains due to low concentrations in human dental enamel (ppb range), requiring thermal ionisation mass spectrometry (TIMS) using 10¹³ Ω resistors. Dental elements (third molars) from 20 individuals born and raised in the Netherlands were analysed for Nd concentration (n = 12) and Nd isotope ratios (n = 15). The geological control on Nd isotope composition was examined using coupled Nd-Sr isotope analysis of the same third molar. Teeth from different geological environments were also analysed (Caribbean, Columbian, and Icelandic, n = 5). Neodymium elemental concentrations in dental elements ranged between 0.1 and 7.9 ppb (median 0.5 ppb). The Dutch ¹⁴³Nd/¹⁴⁴Nd ratios of the provinces of Limburg and Friesland were between 0.5118 and 0.5121, with Dutch ⁸⁷Sr/⁸⁶Sr ratios in agreement with the previously established local range (0.708–0.710). The current findings were compared to previously published results on Nd concentration and composition from Dutch individuals. The concentration of Nd and ¹⁴³Nd/¹⁴⁴Nd ratios were weakly correlated (R² = 0.47, n = 17) in Dutch human dental enamel. The majority (n = 25, 83.3%) of individuals had Nd and Sr isotope values isotopically indistinguishable from the geological environment in which their third molars formed and mineralised. However, the Nd isotope ratios of the Icelandic individual and several Dutch individuals (n = 4) suggested that Nd in enamel is not solely influenced by geological environment. In order for neodymium isotopes to be quantitatively applied in forensic and archaeological settings further analyses of individuals from various geographical regions with well-defined dietary Nd isotope data are required.

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First evaluation of the potential of neodymium isotopes for human provenancing

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Provides insight in Nd concentration and isotope ratios in human dental enamel

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First study presenting Nd isotope ratios from multiple geological settings

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First study combining ¹⁴³Nd/¹⁴⁴Nd and ⁸⁷Sr/⁸⁶Sr ratios of the same dental element

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The use of 10¹³ Ω resistors allows for greater precision analysis of small samples

Composition and spatial distribution of elements and isotopes of a giant human bladder stone and environmental implications

The composition and spatial distribution of minerals, trace elements, as well as carbon and nitrogen isotopes from the outer crust to inner nucleus of a 20-year old giant human bladder stone comprising thirteen layers were intensively investigated. Calcium oxalate monohydrate (COM) was found to concentrate in the inner and middle layers, struvite was concentrated in middle and outer layers, and fluorapatite occurred in almost all layers. The spatial distribution of minerals has the potential to provide preliminary knowledge regarding the long-term urine composition, or even the physiological condition of the patient. The stable carbon isotope ratio (δ¹³C) and stable nitrogen isotope ratio (δ¹⁵N) were measured in each layer and significant correlation was found between δ¹³C with calcium oxalate monohydrate content and between δ¹⁵N and struvite content. Nearly constant values of -23.2‰ and 7.1‰ for δ¹³C and δ¹⁵N, respectively, were found in the organic components of the stone. Both isotope ratios indicate a long-term fixed diet consisting mainly of C3 plants, such as rice and wheat, for the 20-year time period of the stone formation. In addition, eighteen elements (Ca, P, Mg, K, Na, Al, Fe, Zn, Pb, Cu, Sr, Ba, Ti, V, Cr, Ni, Mn and Co) were measured in all the layers. The trace elements Al, Fe, Cu, Zn, Pb, Sr, Ba and Ti showed a similar spatial distribution pattern from the outer crust to the inner core. Although there were complex correlations between elements and minerals, Factor Analysis suggests that the occurrence of these elements in stones may be mainly the result of environmental exposure to metals during the formation of the stone, indicating that urinary stones may serve as potential long-term biomonitors. In particular, Ni and Cr showed a distinct distribution pattern in the stone, which may relate to human metabolic activities.

Comparing apples and oranges: Why infant bone collagen may not reflect dietary intake in the same way as dentine collagen

OBJECTIVES

Recent developments in incremental dentine analysis allowing increased temporal resolution for tissues formed during the first 1,000 days of life have cast doubt on the veracity of weaning studies using bone collagen carbon (δ13 C) and nitrogen (δ15 N) isotope ratio data from infants. Here, we compare published bone data from the well-preserved Anglo-Saxon site of Raunds Furnells, England, with co-forming dentine from the same individuals, and investigate the relationship of these with juvenile stature. The high-resolution isotope data recorded in dentine allow us to investigate the relationship of diet with juvenile stature during this critical period of life.

MATERIALS AND METHODS

We compare incremental dentine collagen δ13 C and δ15 N data to published bone collagen data for 18 juveniles and 5 female adults from Anglo Saxon Raunds Furnells alongside new data for juvenile skeletal and dental age. An improvement in the method by sampling the first 0.5 mm of the sub-cuspal or sub-incisal dentine allows the isotopic measurement of dentine formed in utero.

RESULTS AND DISCUSSION

δ13 C profiles for both dentine and bone are similar and more robust than δ15 N for estimating the age at which weaning foods are introduced. Our results suggest δ15 N values from dentine can be used to evaluate the maternal/in utero diet and physiology during pregnancy, and that infant dentine profiles may reflect diet PLUS an element of physiological stress. In particular, bone collagen fails to record the same range of δ15 N as co-forming dentine, especially where growth is stunted, suggesting that infant bone collagen is unreliable for weaning studies.

The role of infant life histories in the construction of identities in death: An incremental isotope study of dietary and physiological status among children afforded differential burial

OBJECTIVES

Isotope ratio analyses of dentine collagen were used to characterize short-term changes in physiological status (both dietary status and biological stress) across the life course of children afforded special funerary treatment.

MATERIALS AND METHODS

Temporal sequences of δ¹⁵ N and δ¹³ C isotope profiles for incrementally forming dentine collagen were obtained from deciduous teeth of 86 children from four early-medieval English cemeteries. Thirty-one were interred in child-specific burial clusters, and the remainder alongside adults in other areas of the cemetery. Isotope profiles were categorized into four distinct patterns of dietary and health status between the final prenatal months and death.

RESULTS

Isotope profiles from individuals from the burial clusters were significantly less likely to reflect weaning curves, suggesting distinctive breastfeeding and weaning experiences. This relationship was not simply a factor of differential age at death between cohorts. There was no association of burial location neither with stage of weaning at death, nor with isotopic evidence of physiological stress at the end of life.

DISCUSSION

This study is the first to identify a relationship between the extent of breastfeeding and the provision of child-specific funerary rites. Limited breastfeeding may indicate the mother had died during or soon after birth, or that either mother or child was unable to feed due to illness. Children who were not breastfed will have experienced a significantly higher risk of malnutrition, undernutrition and infection. These sickly and perhaps motherless children received care to nourish them during early life, and were similarly provided with special treatment in death.

Economic and demographic predictors of dietary variation and nutritional indicators in Nicaragua

OBJECTIVES

We measured carbon and nitrogen isotopic ratios in a contemporary population, and tested how the isotopic variability relates to measures of socioeconomic status (e.g., household wealth) and anthropometric measures (e.g., standardized height-for-age and weight-for-age z-scores).

METHODS

Hair samples from individuals living in the Bosawas Biosphere Reserve in Nicaragua were analyzed for δ¹³ C and δ¹⁵ N, and these data were examined in relation to individual (e.g., age, sex, anthropometrics) and household (e.g., household size, wealth) variables.

RESULTS

We found through mixed-effects modeling that δ¹³ C and δ¹⁵ N varied predictably with individual age and household wealth. δ¹³ C and δ¹⁵ N did not, however, improve models predicting variation in individual anthropometric measures.

CONCLUSION

These results indicate that, although there is a relationship between diet (δ¹³ C and δ¹⁵ N) and socioeconomic variables, these dietary differences are not the main cause of health differences in this population.

Let's talk about stress, baby! Infant-feeding practices and stress in the ancient Atacama desert, Northern Chile

AIMS AND OBJECTIVES

The transition to an agricultural economy is often presumed to involve an increase in female fertility related to changes in weaning practice. In particular, the availability of staple crops as complementary foods is hypothesized to allow earlier weaning in agricultural populations. In this study, our primary aim is to explore whether this model fits the agricultural transition in the Atacama Desert using incremental isotopic analysis. A secondary aim of this study is to identify isotopic patterns relating to weaning, and assess how these may be differentiated from those relating to early life stress.

MATERIALS AND METHODS

We use incremental isotopic analysis of dentine to examine changes in δ¹⁵ N and δ¹³ C values from infancy and childhood in sites of the Arica region (n = 30). We compare individuals from pre-agricultural and agricultural phases to establish isotopic patterns and relate these patterns to maternal diet, weaning trajectory and physiological stress.

RESULTS

We find that there is no evidence for systematic temporal or geographic variation in incremental isotopic results. Instead, results from all time periods are highly variable, with weaning completed between 1.5 and 3.5 years. Characteristics of the incremental profiles indicate that both in utero and postnatal stress were a common part of the infant experience in the Atacama.

DISCUSSION

In the Atacama Desert it appears that the arrival of agricultural crops did not result in uniform shifts in weaning behavior. Instead, infant and child diet seems to have been dictated by the broad-spectrum diets of the mothers, perhaps as a way of mitigating the stresses of the harsh desert environment.

Stable C and N isotope analysis of hair suggest undernourishment as a factor in the death of a mummified girl from late 19th century San Francisco, CA

The chance discovery of a 1.5–3.5 years old mummified girl presents a unique opportunity to further our understanding of health and disease among children in 19^th Century San Francisco. This study focuses on carbon and nitrogen stable isotope signatures in serial samples of hair that cover the last 14 months of her life. Results suggest an initial omnivorous diet with little input from marine resources or C4 plants. Around six months before death δ¹⁵N starts a steady increase, with a noticeable acceleration just two months before she died. The magnitude of δ¹⁵N change, +1.5‰ in total, is consistent with severe undernourishment or starvation. Cemetery records from this time period in San Francisco indicate high rates of infant and child mortality, mainly due to bacterial-borne infectious diseases, about two orders of magnitude higher than today. Taken together, we hypothesize that the girl died after a prolonged battle with such an illness. Results highlight the tremendous impacts that modern sanitation and medicine have had since the 1800s on human health and lifespan in the United States.

Prediction of human dietary δ15N intake from standardised food records: validity and precision of single meal and 24-h diet data

Natural stable isotope ratios (δ¹⁵N) of humans can be used for nutritional analyses and dietary reconstruction of modern and historic individuals and populations. Information about an individual's metabolic state can be obtained by comparison of tissue and dietary δ¹⁵N. Different methods have been used to estimate dietary δ¹⁵N in the past; however, the validity of such predictions has not been compared to experimental values. For a total of 56 meals and 21 samples of 24-h diets, predicted and experimental δ¹⁵N values were compared. The δ¹⁵N values were predicted from self-recorded food intake and compared with experimental δ¹⁵N values. Predicted and experimental δ¹⁵N values were in good agreement for meals and preparations (r = 0.89, p < .001) as well as for the 24-h diets (r = 0.76, p < .001). Dietary δ¹⁵N was mainly determined by the amount of fish, whereas the contribution of meat to dietary δ¹⁵N values was less pronounced. Prediction of human dietary δ¹⁵N values using standardised food records and representative δ¹⁵N data sets yields reliable data for dietary δ¹⁵N intake. A differentiated analysis of the primary protein sources is necessary when relating the proportion of animal-derived protein in the diet by δ¹⁵N analysis.

Case of Fatal Starvation: Can Stable Isotope Analysis Serve to Support Morphological Diagnosis and Approximate the Length of Starvation?

The diagnosis of death as a result of starvation is established on anthropological measurements, visual appearance of the deceased on external and internal examination, microscopic analysis, laboratory testing, and exclusion of other causes of death. Herein, we present our findings on a case of 95-year-old man who died of starvation. After the diagnosis of starvation was established by traditional forensic medicine methods, we have conducted retrospective segmental analysis of stable carbon (δ¹³ C) and nitrogen (δ¹⁵ N) isotope ratios in hair sample. This method reveals periods of starvation through decrease in δ¹³ C and increase in δ¹⁵ N along the strand of hair. Our analysis revealed the decrease of 0.6 ‰ in δ¹³ C during the last 10-12 weeks prior to death, similar as reported in other investigations. Also, a decrease of 0.7 ‰ in δ¹⁵ N during the last 8-10 weeks prior to death was determined that was different than observed in previous studies.

The Great Irish Famine: Identifying Starvation in the Tissues of Victims Using Stable Isotope Analysis of Bone and Incremental Dentine Collagen

The major components of human diet both past and present may be estimated by measuring the carbon and nitrogen isotope ratios (δ¹³C and δ¹⁵N) of the collagenous proteins in bone and tooth dentine. However, the results from these two tissues differ substantially: bone collagen records a multi-year average whilst primary dentine records and retains time-bound isotope ratios deriving from the period of tooth development. Recent studies harnessing a sub-annual temporal sampling resolution have shed new light on the individual dietary histories of our ancestors by identifying unexpected radical short-term dietary changes, the duration of breastfeeding and migration where dietary change occurs, and by raising questions regarding factors other than diet that may impact on δ¹³C and δ¹⁵N values. Here we show that the dentine δ¹³C and δ¹⁵N profiles of workhouse inmates dating from the Great Irish Famine of the 19th century not only record the expected dietary change from C₃ potatoes to C₄ maize, but when used together they also document prolonged nutritional and other physiological stress resulting from insufficient sustenance. In the adults, the influence of the maize-based diet is seen in the δ¹³C difference between dentine (formed in childhood) and rib (representing an average from the last few years of life). The demonstrated effects of stress on the δ¹³C and δ¹⁵N values will have an impact on the interpretations of diet in past populations even in slow-turnover tissues such as compact bone. This technique also has applicability in the investigation of modern children subject to nutritional distress where hair and nails are unavailable or do not record an adequate period of time.

Trial application of oxygen and carbon isotope analysis in tooth enamel for identification of past-war victims for discriminating between Japanese and US soldiers

Stable isotope analysis has undergone rapid development in recent years and yielded significant results in the field of forensic sciences. In particular, carbon and oxygen isotopic ratios in tooth enamel obtained from human remains can provide useful information for the crosschecking of morphological and DNA analyses and facilitate rapid on-site prescreening for the identification of remains. This study analyzes carbon and oxygen isotopic ratios in the tooth enamel of Japanese people born between 1878 and 1930, in order to obtain data for methodological differentiation of Japanese and American remains from the Second World War. The carbon and oxygen isotopic ratios in the tooth enamel of the examined Japanese individuals are compared to previously reported data for American individuals (born post WWII), and statistical analysis is conducted using a discrimination method based on a logistic regression analysis. The discrimination between the Japanese and US populations, including Alaska and Hawaii, is found to be highly accurate. Thus, the present method has potential as a discrimination technique for both populations for use in the examination of mixed remains comprising Japanese and American fallen soldiers.

Global spatial distributions of nitrogen and carbon stable isotope ratios of modern human hair

RATIONALE

Natural stable carbon (δ(13)C) and nitrogen isotope ratios (δ(15)N) of humans are related to individual dietary habits and environmental and physiological factors. In forensic science the stable isotope ratios of human remains such as hair and nail are used for geographical allocation. Thus, knowledge of the global spatial distribution of human δ(13)C and δ(15)N values is an essential component in the interpretation of stable isotope analytical results.

METHODS

No substantial global datasets of human stable isotope ratios are currently available, although the amount of available (published) data has increased within recent years. We have herein summarised the published data on human global δ(13)C andδ(15)N values (around 3600 samples) and added experimental values of more than 400 additional worldwide human hair and nail samples. In order to summarise isotope ratios for hair and nail samples correction factors were determined.

RESULTS

The current available dataset of human stable isotope ratios is biased towards Europe and North America with only limited data for countries in Africa, Central and South America and Southeast Asia. The global spatial distribution of carbon isotopes is related to latitude and supports the fact that human δ(13)C values are dominated by the amount of C4 plants in the diet, either due to direct ingestion as plant food, or by its use as animal feed. In contrast, the global spatial distribution of human δ(15)N values is apparently not exclusively related to the amount of fish or meat ingested, but also to environmental factors that influence agricultural production.

CONCLUSIONS

There are still a large proportion of countries, especially in Africa, where there are no available data for human carbon and nitrogen isotope ratios. Although the interpretation of modern human carbon isotope ratios at the global scale is quite possible, and correlates with the latitude, the potential influences of extrinsic and/or intrinsic factors on human nitrogen isotope ratios have to be taken into consideration.