Association of protein intakes and variation of diet‐scalp hair nitrogen isotopic discrimination factor in Papua New Guinea highlanders. Issue 3 (14th July 2015)

• Record Type: Journal Article
• Authors: Naito, Yuichi I.; Morita, Ayako; Natsuhara, Kazumi; Tadokoro, Kiyoshi; Baba, Jun; Odani, Shingo; Tomitsuka, Eriko; Igai, Katsura; Tsutaya, Takumi; Yoneda, Minoru; Greenhill, Andrew R.; Horwood, Paul F.; Soli, Kevin W.; Phuanukoonnon, Suparat; Siba, Peter M.; Umezaki, Masahiro
• Is Part Of: American journal of physical anthropology. Volume 158:Issue 3(2015)
• Page Start: 359
• Page End: 370
• Publication Date: 2015-07-14
• Subjects: Physical anthropology -- Periodicals; Anthropology -- Periodicals; Anthropologie physique -- Périodiques; 599.9
• DOI: 10.1002/ajpa.22798
• Languages: English
• ISSNs: 0002-9483

Abstract

<abstract abstract-type="main"> <title>ABSTRACT</title> <sec id="ajpa22798-sec-0001" sec-type="section"> <title>Objectives:</title> <p>We present new nitrogen isotopic discrimination factor between diets and scalp hairs (Δ<sup>15</sup>N<sub>Hair‐Diet</sub>: δ<sup>15</sup>N<sub>Hair</sub> – δ<sup>15</sup>N<sub>Diet</sub>) for indigenous residents in three communities in the Papua New Guinea Highlands who consumed various amounts and qualities of protein. The Δ<sup>15</sup>N is important for precise evaluation of the dietary habits of human populations; in both contemporary and traditional lifestyles. Several hypotheses have been proposed regarding factors that affect Δ<sup>15</sup>N values, based largely on observations from animal feeding experiments. However, variations and factors controlling Δ<sup>15</sup>N in humans are not well understood, mainly due to the difficulty of controlling the diets of participants.</p> </sec> <sec id="ajpa22798-sec-0002" sec-type="section"> <title>Materials and Methods:</title> <p>These residents were studied because they have maintained relatively traditional dietary habits, which allow quantitative recording of diets. Δ<sup>15</sup>N was estimated by comparing hair δ<sup>15</sup>N values to mean dietary δ<sup>15</sup>N values calculated from the recorded intake of each food item and their δ<sup>15</sup>N values.</p> </sec> <sec id="ajpa22798-sec-0003" sec-type="section"> <title>Results:</title> <p>The results showed that: i) there was a significant difference in Δ<sup>15</sup>N among study locations (3.9 ± 0.9‰ for most urbanized, 5.2 ± 1.0‰ for medium and 5.0 ± 0.9‰ for least urbanized communities; range = 1.2–7.3‰ for all participants); and ii) estimated Δ<sup>15</sup>N values were negatively correlated with several indicators of animal protein intake (% nitrogen in diet: range = 0.9–7.6%).</p> </sec> <sec id="ajpa22798-sec-0004" sec-type="section"> <title>Discussion:</title> <p>We hypothesize that a combination of several factors, which presumably included urea recycling and amino acid and protein recycling and/or <italic>de novo</italic> synthesis during metabolic processes, altered the Δ<sup>15</sup>N values of the participants. Am J Phys Anthropol 158:359–370, 2015. © 2015 Wiley Periodicals, Inc.</p> </sec> </abstract>