The University of Southampton
University of Southampton Institutional Repository

Small organs with a high metabolic rate explain lower resting energy expenditure in African American than in white adults

Small organs with a high metabolic rate explain lower resting energy expenditure in African American than in white adults
Small organs with a high metabolic rate explain lower resting energy expenditure in African American than in white adults
Background: African Americans have a lower resting energy expenditure (REE) relative to fat-free mass (FFM) than do whites. Whether the composition of FFM at the organ-tissue level differs between African Americans and whites and, if so, whether that difference could account for differences by race in REE are unknown.
Objective: The objectives were to quantify FFM in vivo in women and men at the organ-tissue level and to ascertain whether the mass of specific high-metabolic-rate organs and tissues differs between African Americans and whites and, if so, whether that difference can account for differences in REE.
Design: The study was a cross-sectional evaluation of 64 women (n = 34 African Americans, 30 whites) and 35 men (n = 8 African Americans, 27 whites). Magnetic resonance imaging measures of liver, kidney, heart, spleen, brain, skeletal muscle, and adipose tissue and dual-energy X-ray absorptiometry measures of fat and FFM were acquired. REE was measured by using indirect calorimetry.
Results: The mass of selected high-metabolic-rate organs (sum of liver, heart, spleen, kidneys, and brain) after adjustment for fat, FFM, sex, and age was significantly (P < 0.001) smaller in African Americans than in whites (3.1 and 3.4 kg, respectively; ± SEE difference: 0.30 ± 0.06 kg). In a multiple regression analysis with fat, FFM, sex, age, and race as predictors of REE, the addition of the total mass rendered race nonsignificant.
Conclusions: Racial differences in REE were reduced by >50% and were no longer significant when the mass of specific high-metabolic-rate organs was considered. Differences in FFM composition may be responsible for the reported REE differences.
race, ethnicity, african americans, whites, metabolism, organs, tissues, fat-free mass, resting energy expenditure, magnetic resonance imaging
0002-9165
1062-1067
Gallagher, Dympna
056030c9-2862-4ac9-bed6-cf7045a73d61
Albu, Jeanine
c862a56d-e663-4ba9-afa0-ed625938bbee
He, Qing
94baedd4-45f0-436e-83d4-4e2ebcd1bec3
Heshka, Stanley
a7d06276-ab84-467b-957c-aea529eac90c
Boxt, Lawrence
17dfea38-4d02-4ae3-9a17-4b29c2adf614
Krasnow, Norman
ed0c9e81-e222-48c6-b756-14f5a3d17e3e
Elia, Marionos
964bf436-e623-46d6-bc3f-5dd04c9ef4c1
Gallagher, Dympna
056030c9-2862-4ac9-bed6-cf7045a73d61
Albu, Jeanine
c862a56d-e663-4ba9-afa0-ed625938bbee
He, Qing
94baedd4-45f0-436e-83d4-4e2ebcd1bec3
Heshka, Stanley
a7d06276-ab84-467b-957c-aea529eac90c
Boxt, Lawrence
17dfea38-4d02-4ae3-9a17-4b29c2adf614
Krasnow, Norman
ed0c9e81-e222-48c6-b756-14f5a3d17e3e
Elia, Marionos
964bf436-e623-46d6-bc3f-5dd04c9ef4c1

Gallagher, Dympna, Albu, Jeanine, He, Qing, Heshka, Stanley, Boxt, Lawrence, Krasnow, Norman and Elia, Marionos (2006) Small organs with a high metabolic rate explain lower resting energy expenditure in African American than in white adults. American Journal of Clinical Nutrition, 83 (5), 1062-1067.

Record type: Article

Abstract

Background: African Americans have a lower resting energy expenditure (REE) relative to fat-free mass (FFM) than do whites. Whether the composition of FFM at the organ-tissue level differs between African Americans and whites and, if so, whether that difference could account for differences by race in REE are unknown.
Objective: The objectives were to quantify FFM in vivo in women and men at the organ-tissue level and to ascertain whether the mass of specific high-metabolic-rate organs and tissues differs between African Americans and whites and, if so, whether that difference can account for differences in REE.
Design: The study was a cross-sectional evaluation of 64 women (n = 34 African Americans, 30 whites) and 35 men (n = 8 African Americans, 27 whites). Magnetic resonance imaging measures of liver, kidney, heart, spleen, brain, skeletal muscle, and adipose tissue and dual-energy X-ray absorptiometry measures of fat and FFM were acquired. REE was measured by using indirect calorimetry.
Results: The mass of selected high-metabolic-rate organs (sum of liver, heart, spleen, kidneys, and brain) after adjustment for fat, FFM, sex, and age was significantly (P < 0.001) smaller in African Americans than in whites (3.1 and 3.4 kg, respectively; ± SEE difference: 0.30 ± 0.06 kg). In a multiple regression analysis with fat, FFM, sex, age, and race as predictors of REE, the addition of the total mass rendered race nonsignificant.
Conclusions: Racial differences in REE were reduced by >50% and were no longer significant when the mass of specific high-metabolic-rate organs was considered. Differences in FFM composition may be responsible for the reported REE differences.

Text
1062.pdf - Version of Record
Restricted to Repository staff only
Request a copy

More information

Published date: May 2006
Additional Information: Original research communication
Keywords: race, ethnicity, african americans, whites, metabolism, organs, tissues, fat-free mass, resting energy expenditure, magnetic resonance imaging

Identifiers

Local EPrints ID: 44173
URI: http://eprints.soton.ac.uk/id/eprint/44173
ISSN: 0002-9165
PURE UUID: c6f0bdf1-c276-4088-af01-c66bf5eeebb6

Catalogue record

Date deposited: 19 Feb 2007
Last modified: 15 Mar 2024 09:01

Export record

Contributors

Author: Dympna Gallagher
Author: Jeanine Albu
Author: Qing He
Author: Stanley Heshka
Author: Lawrence Boxt
Author: Norman Krasnow
Author: Marionos Elia

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×