Substantial Fat Loss in Physique Competitors Is Characterized by Increased Levels of Bile Acids, Very-Long Chain Fatty Acids, and Oxylipins.


Type
Article
Change log
Authors
Sarin, Heikki V 
Qin, Youwen 
Inouye, Michael 
Ritchie, Scott C 
Abstract

Weight loss and increased physical activity may promote beneficial modulation of the metabolome, but limited evidence exists about how very low-level weight loss affects the metabolome in previously non-obese active individuals. Following a weight loss period (21.1 ± 3.1 weeks) leading to substantial fat mass loss of 52% (−7.9 ± 1.5 kg) and low body fat (12.7 ± 4.1%), the liquid chromatography-mass spectrometry-based metabolic signature of 24 previously young, healthy, and normal weight female physique athletes was investigated. We observed uniform increases (FDR < 0.05) in bile acids, very-long-chain free fatty acids (FFA), and oxylipins, together with reductions in unsaturated FFAs after weight loss. These widespread changes, especially in the bile acid profile, were most strongly explained (FDR < 0.05) by changes in android (visceral) fat mass. The reported changes did not persist, as all of them were reversed after the subsequent voluntary weight regain period (18.4 ± 2.9 weeks) and were unchanged in non-dieting controls (n = 16). Overall, we suggest that the reported changes in FFA, bile acid, and oxylipin profiles reflect metabolic adaptation to very low levels of fat mass after prolonged periods of intense exercise and low-energy availability. However, the effects of the aforementioned metabolome subclass alteration on metabolic homeostasis remain controversial, and more studies are warranted to unravel the complex physiology and potentially associated health implications. In the end, our study reinforced the view that transient weight loss seems to have little to no long-lasting molecular and physiological effects.

Description

Funder: Finnish Foundation for Cardiovascular Research


Funder: Finnish Diabetes Research Foundation


Funder: University of Helsinki


Funder: Helsinki University Hospital Government Research Funds


Funder: University of Helsinki and Helsinki University Hospital Government Research


Funder: The Finnish Medical Foundation

Keywords
LC-MS metabolome, bioactive metabolites, exercise, visceral fat mass, weight loss
Journal Title
Metabolites
Conference Name
Journal ISSN
2218-1989
2218-1989
Volume Title
12
Publisher
MDPI AG
Sponsorship
National Institute for Health and Care Research (IS-BRC-1215-20014)