Dietary α‐Linolenic Acid, Marine ω‐3 Fatty Acids, and Mortality in a Population With High Fish Consumption: Findings From the PREvención con DIeta MEDiterránea (PREDIMED) Study

Background: Epidemiological evidence suggests a cardioprotective role of α‐linolenic acid (ALA), a plant‐derived ω‐3 fatty acid. It is unclear whether ALA is beneficial in a background of high marine ω‐3 fatty acids (long‐chain n‐3 polyunsaturated fatty acids) intake. In persons at high cardiovascular risk from Spain, a country in which fish consumption is customarily high, we investigated whether meeting the International Society for the Study of Fatty Acids and Lipids recommendation for dietary ALA (0.7% of total energy) at baseline was related to all‐cause and cardiovascular disease mortality. We also examined the effect of meeting the society's recommendation for long‐chain n‐3 polyunsaturated fatty acids (≥500 mg/day). Methods and Results: We longitudinally evaluated 7202 participants in the PREvención con DIeta MEDiterránea (PREDIMED) trial. Multivariable‐adjusted Cox regression models were fitted to estimate hazard ratios. ALA intake correlated to walnut consumption (r=0.94). During a 5.9‐y follow‐up, 431 deaths occurred (104 cardiovascular disease, 55 coronary heart disease, 32 sudden cardiac death, 25 stroke). The hazard ratios for meeting ALA recommendation (n=1615, 22.4%) were 0.72 (95% CI 0.56–0.92) for all‐cause mortality and 0.95 (95% CI 0.58–1.57) for fatal cardiovascular disease. The hazard ratios for meeting the recommendation for long‐chain n‐3 polyunsaturated fatty acids (n=5452, 75.7%) were 0.84 (95% CI 0.67–1.05) for all‐cause mortality, 0.61 (95% CI 0.39–0.96) for fatal cardiovascular disease, 0.54 (95% CI 0.29–0.99) for fatal coronary heart disease, and 0.49 (95% CI 0.22–1.01) for sudden cardiac death. The highest reduction in all‐cause mortality occurred in participants meeting both recommendations (hazard ratio 0.63 [95% CI 0.45–0.87]). Conclusions: In participants without prior cardiovascular disease and high fish consumption, dietary ALA, supplied mainly by walnuts and olive oil, relates inversely to all‐cause mortality, whereas protection from cardiac mortality is limited to fish‐derived long‐chain n‐3 polyunsaturated fatty acids. Clinical Trial Registration URL: http://www.Controlled-trials.com/. Unique identifier: ISRCTN35739639

Mobility in the Atacama Desert, northern Chile, in the Late Intermediate Period (AD 900–1450): A re-evaluation using stable isotope analysis

Research on the Late Intermediate Period (AD 900–1450) in northern Chile has been strongly influenced by two mobility models: John Murra's classic vertical ecological archipelago model, with highland colonies in the lowlands; and the gyratory mobility model, with pastoralists and their llama caravans controlling trade. The widespread application of these two models, however, suffers from a lack of supporting archaeological evidence. Stable isotope analysis provides a more direct approach for studying both diet and mobility patterns, complementing material culture studies. The aim of this paper is to evaluate the presence of colonies and/or specialised highland caravans in the lowlands of northern Chile through the application of δ13C, δ15N and δ18O to human tooth enamel, bone collagen and bone apatite. The results show strong local traditions in terms of diet and mobility associated with the Loa-San Pedro, Antofagasta and Pica-Tarapacá cultural groups. Our results suggest a non-local origin for some individuals in Pica-Tarapacá and Loa-San Pedro, but provide little evidence to support either the presence of ‘colonies’ or of specialised ‘caravans’. Mobility patterns were, instead, diverse and flexible, including female and male individuals that moved at different moments of their lives

A chronology for the earliest human burials at Cuchipuy, central Chile

Cuchipuy is an archaeological site within the ancient Laguna de Tagua Tagua area (O’Higgins Region, central Chile; known for containing the remains of extinct fauna), with evidence for cultural activity spanning most of the Holocene, including over 50 human burials. The bulk of chronometric work at Cuchipuy was carried out in the 1980s, where a discrepancy within the radiocarbon dating results raised questions on the antiquity of the oldest funerary deposits (Stratum 4). Given the importance of both the site and area in prehistoric studies, this analysis aimed to reassess the chronology of Stratum 4 through the production of new radiocarbon dates on human remains and the application of Bayesian modelling. When combined with previously published ages, results place the commencement of Stratum 4 at 7320–7160 cal BP, within the early-mid Holocene. This is later than previous conclusions based on the discrepant dataset, refuting a temporal connection to Paleoindian deposits within the region. In addition, stable light isotope results suggest that human diet during the period was diverse, relying on both terrestrial and freshwater aquatic resources. This pattern changes with later populations, however, where the isotopic signal reflects the consumption of mainly terrestrial resources

Paired radiocarbon dating on human samples and camelid fibers and textiles from northern Chile: the case of Pica 8

Pica 8 is a Late Intermediate Period (AD 900-1450) cemetery located in the Atacama Desert. Burials at the site present unexpectedly high variability in δ13C (-8‰ to -16‰) and δ15N (10‰ to 24‰) values in their skeletal tissues implying highly diverse diets. There are two possible explanations for this variability: the first is diachronic change in diet and the second synchronic socio-cultural distinctions. To distinguish between them a radiocarbon dating program (n = 23) was initiated. The presumed importance of marine foods adds the complication of a marine reservoir effect. To address this problem, paired radiocarbon dates were obtained on human bone and camelid textiles from nine graves. The results fall into two groups, one showing an average offset of 117 ± 9 14C yr, and the other no statistically significant offsets. We conclude that the contribution of marine foods to bone collagen at Pica 8 was less than previously supposed. Other factors must be invoked to account for the unusually high human δ15N values at the site. Manuring crops with sea-bird guano emerges as a probable explanation. No relationship with chronology is seen implying the presence of considerable diversity in diets and hence lifeways within the Pica 8 community

‘White gold’ guano fertilizer drove agricultural intensification in the Atacama Desert from AD 1000

The archaeological record shows that large pre-Inca agricultural systems supported settlements for centuries around the ravines and oases of northern Chile’s hyperarid Atacama Desert. This raises questions about how such productivity was achieved and sustained, and its social implications. Using isotopic data of well-preserved ancient plant remains from Atacama sites, we show a dramatic increase in crop nitrogen isotope values (δ15N) from around AD 1000. Maize was most affected, with δ15N values as high as +30‰, and human bone collagen following a similar trend; moreover, their carbon isotope values (δ13C) indicate a considerable increase in the consumption of maize at the same time. We attribute the shift to extremely high δ15N values—the highest in the world for archaeological plants—to the use of seabird guano to fertilize crops. Guano—‘white gold’ as it came to be called—thus sustained agricultural intensification, supporting a substantial population in an otherwise extreme environment

Two ancient human genomes reveal Polynesian ancestry among the indigenous Botocudos of Brazil.

Understanding the peopling of the Americas remains an important and challenging question. Here, we present (14)C dates, and morphological, isotopic and genomic sequence data from two human skulls from the state of Minas Gerais, Brazil, part of one of the indigenous groups known as 'Botocudos'. We find that their genomic ancestry is Polynesian, with no detectable Native American component. Radiocarbon analysis of the skulls shows that the individuals had died prior to the beginning of the 19th century. Our findings could either represent genomic evidence of Polynesians reaching South America during their Pacific expansion, or European-mediated transport

Two ancient human genomes reveal Polynesian ancestry among the indigenous Botocudos of Brazil.

Understanding the peopling of the Americas remains an important and challenging question. Here, we present (14)C dates, and morphological, isotopic and genomic sequence data from two human skulls from the state of Minas Gerais, Brazil, part of one of the indigenous groups known as 'Botocudos'. We find that their genomic ancestry is Polynesian, with no detectable Native American component. Radiocarbon analysis of the skulls shows that the individuals had died prior to the beginning of the 19th century. Our findings could either represent genomic evidence of Polynesians reaching South America during their Pacific expansion, or European-mediated transport.GeoGenetics members were supported by the Lundbeck Foundation, the Danish National Research Foundation (DNRF94) and the European Union (FP7/2007-2013/317184 and 319209). A.S.M. was supported by a fellowship from the Swiss National Science Foundation (PBSKP3_143529); M.D. by the US National Science Foundation (grant DBI-1103639); P.L.J. by the National Institutes of Health (grant K99 GM104158); V.F.G. by a Strategic Training for Advanced Genetic Epidemiology (STAGE) fellowship, University of Toronto.This is the final version. It was first published by Elsevier at http://www.sciencedirect.com/science/article/pii/S096098221401274