{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,8]],"date-time":"2026-03-08T20:13:21Z","timestamp":1773000801208,"version":"3.50.1"},"reference-count":25,"publisher":"Wiley","issue":"2","license":[{"start":{"date-parts":[[2026,2,17]],"date-time":"2026-02-17T00:00:00Z","timestamp":1771286400000},"content-version":"vor","delay-in-days":16,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"},{"start":{"date-parts":[[2026,2,1]],"date-time":"2026-02-01T00:00:00Z","timestamp":1769904000000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"funder":[{"DOI":"10.13039\/100007492","name":"Baylor University","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100007492","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["American J Hum Biol"],"published-print":{"date-parts":[[2026,2]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>Intestinal function is an important but often overlooked aspect of human biological variation, with the intestines serving as both a barrier against external pathogens\/contaminants and the primary conduit of nutrient extraction from food. Impaired intestinal function among children is viewed as a key contributor to growth faltering globally. However, few studies have investigated children's intestinal function in rural settings or beyond infancy. To address this limitation, we conducted a pilot study to describe the intestinal function of school\u2010age Indigenous Shuar children of Amazonian Ecuador and to assess the feasibility of implementing the widely utilized lactulose:mannitol (L:M) test of absorption and permeability with this group.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>The urinary L:M test was performed with 23 rural\u2010living Shuar children aged 4\u201312\u2009years. Ultra\u2010performance liquid chromatograph\u2013high\u2010resolution mass spectrometry was used to determine L:M ratios, lactulose recovery, and mannitol recovery. Age and sex patterns were investigated using linear regression models.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Children's mean L:M ratio was 0.33\u2009\u00b1\u20090.32, a ratio comparable to values reported for children in other low\u2010 and middle\u2010income settings. 35%\u201391% of children were categorized as having impaired intestinal function using common cut\u2010off values. Children's lactulose (0.14%\u2009\u00b1\u20090.17%) and mannitol (2.60%\u2009\u00b1\u20092.22%) recoveries did not differ by sex but increased with age (\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&lt;\u20090.05) and indicated diminished intestinal absorptive capacity and increased permeability.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Intestinal function appears to be considerably impaired among school\u2010age Shuar children living in a low\u2010resource, rural setting. Children living in unsanitary, non\u2010industrialized contexts may routinely experience intestinal permeability\u2010related immune activation and malabsorption\u2010related energy\/nutrient loss. More research is needed to explore the breadth of global variation in children's intestinal function and to investigate its many evolutionary and public health implications.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1002\/ajhb.70219","type":"journal-article","created":{"date-parts":[[2026,2,18]],"date-time":"2026-02-18T06:19:26Z","timestamp":1771395566000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Impaired Intestinal Function Among Indigenous Shuar Children of Amazonian Ecuador: Evidence From Lactulose:Mannitol Tests of Absorption and Permeability"],"prefix":"10.1002","volume":"38","author":[{"ORCID":"https:\/\/orcid.org\/0009-0003-0398-6768","authenticated-orcid":false,"given":"Marcela","family":"Pfaff\u2010Nash","sequence":"first","affiliation":[{"name":"Department of Anthropology Baylor University  Waco Texas USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alejandro J.","family":"Ramirez","sequence":"additional","affiliation":[{"name":"Mass Spectrometry Center Baylor University  Waco Texas USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Elizabeth Y.","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Biology Baylor University  Waco Texas USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hannah N.","family":"Cantrell","sequence":"additional","affiliation":[{"name":"Department of Anthropology University of Oregon  Eugene Oregon USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8013-6773","authenticated-orcid":false,"given":"Melissa A.","family":"Liebert","sequence":"additional","affiliation":[{"name":"Department of Anthropology Northern Arizona University  Flagstaff Arizona USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5442-232X","authenticated-orcid":false,"given":"Felicia C.","family":"Madimenos","sequence":"additional","affiliation":[{"name":"Department of Anthropology Queens College (CUNY)  Queens New York USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"J. Josh","family":"Snodgrass","sequence":"additional","affiliation":[{"name":"Department of Anthropology University of Oregon  Eugene Oregon USA"},{"name":"Global Station for Indigenous Studies &amp; Cultural Diversity Hokkaido University  Sapporo Hokkaido Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lawrence S.","family":"Sugiyama","sequence":"additional","affiliation":[{"name":"Department of Anthropology University of Oregon  Eugene Oregon USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6489-4117","authenticated-orcid":false,"given":"Samuel S.","family":"Urlacher","sequence":"additional","affiliation":[{"name":"Department of Anthropology Baylor University  Waco Texas USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"311","published-online":{"date-parts":[[2026,2,17]]},"reference":[{"key":"e_1_2_9_2_1","doi-asserted-by":"publisher","DOI":"10.1111\/mcn.13315"},{"key":"e_1_2_9_3_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ajcnut.2025.10.023"},{"key":"e_1_2_9_4_1","doi-asserted-by":"publisher","DOI":"10.1093\/nutrit\/nuy068"},{"key":"e_1_2_9_5_1","doi-asserted-by":"publisher","DOI":"10.1079\/BJN2002697"},{"key":"e_1_2_9_6_1","doi-asserted-by":"publisher","DOI":"10.1002\/ajpa.23897"},{"key":"e_1_2_9_7_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.eclinm.2022.101403"},{"key":"e_1_2_9_8_1","doi-asserted-by":"publisher","DOI":"10.1093\/cid\/ciu541"},{"key":"e_1_2_9_9_1","doi-asserted-by":"publisher","DOI":"10.1093\/ajcn\/82.5.1040"},{"key":"e_1_2_9_10_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.dld.2014.02.010"},{"key":"e_1_2_9_11_1","doi-asserted-by":"publisher","DOI":"10.4269\/ajtmh.18\u20100143"},{"key":"e_1_2_9_12_1","doi-asserted-by":"publisher","DOI":"10.1017\/S2040174417000071"},{"key":"e_1_2_9_13_1","doi-asserted-by":"publisher","DOI":"10.4269\/ajtmh.12\u20100629"},{"key":"e_1_2_9_14_1","doi-asserted-by":"publisher","DOI":"10.1017\/S0029665100000173"},{"key":"e_1_2_9_15_1","doi-asserted-by":"publisher","DOI":"10.1097\/MPG.0b013e3181aa3aa9"},{"key":"e_1_2_9_16_1","doi-asserted-by":"publisher","DOI":"10.1097\/MPG.0000000000002834"},{"key":"e_1_2_9_17_1","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0220397"},{"key":"e_1_2_9_18_1","doi-asserted-by":"publisher","DOI":"10.1177\/1535370218768508"},{"key":"e_1_2_9_19_1","doi-asserted-by":"publisher","DOI":"10.1086\/315920"},{"key":"e_1_2_9_20_1","doi-asserted-by":"publisher","DOI":"10.2147\/PHMT.S387747"},{"key":"e_1_2_9_21_1","doi-asserted-by":"publisher","DOI":"10.1002\/ajpa.24719"},{"key":"e_1_2_9_22_1","doi-asserted-by":"publisher","DOI":"10.1002\/ajhb.22747"},{"key":"e_1_2_9_23_1","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.1717522115"},{"key":"e_1_2_9_24_1","doi-asserted-by":"publisher","DOI":"10.1080\/17474124.2017.1343143"},{"key":"e_1_2_9_25_1","doi-asserted-by":"publisher","DOI":"10.1097\/MPG.0b013e3182650a4d"},{"key":"e_1_2_9_26_1","doi-asserted-by":"publisher","DOI":"10.1002\/ajhb.23563"}],"container-title":["American Journal of Human Biology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/ajhb.70219","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/full-xml\/10.1002\/ajhb.70219","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/ajhb.70219","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,3,8]],"date-time":"2026-03-08T17:46:38Z","timestamp":1772991998000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/ajhb.70219"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,2]]},"references-count":25,"journal-issue":{"issue":"2","published-print":{"date-parts":[[2026,2]]}},"alternative-id":["10.1002\/ajhb.70219"],"URL":"https:\/\/doi.org\/10.1002\/ajhb.70219","archive":["Portico"],"relation":{},"ISSN":["1042-0533","1520-6300"],"issn-type":[{"value":"1042-0533","type":"print"},{"value":"1520-6300","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,2]]},"assertion":[{"value":"2025-09-01","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-01-26","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-02-17","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"e70219"}}