A single oral dose of saturated fat impaired hepatic metabolic responses and increased the risk for developing nonalcoholic fatty liver disease (NAFLD) and insulin resistance in healthy adults, according to a new study.
The study included 14 healthy, nonobese men who were randomly assigned to consume a glass of water or a glass of flavored palm oil. Researchers measured the effects of palm oil on the metabolism using in vivo 13C/31P/1H and ex vivo 2H magnetic resonance spectroscopy before and during hyperinsulinemic-euglycemic clamps with isotope dilution.
The palm oil solution contained a saturated fat content equal to a cheeseburger (110-grams with 18-25 grams per 1000 kcal of saturated fat) and large portion of French fries (7-14 grams per 1000 kcal of saturated fat), or an 8-slice pepperoni pizza (approximately 16.72 grams of saturated fat/110 grams) In addition, researchers performed the same experiment using a mouse model.
Analysis of data from human participants showed that the palm oil solution decreased whole-body insulin sensitivity by 25%, hepatic sensitivity by 25%, and adipose tissue sensitivity by 34%. Likewise, hepatic triglyceride content rose by 35%, and hepatic adenosine triphosphate (ATP) content rose by 16%. The net glycogenolysis declined by 20%, and the hepatic gluconeogenesis (GNG) increased by 70%.
In addition, the analysis of mouse transcriptomics showed that palm oil differentially regulated upstream regulators and pathways, including lipopolysaccharides (LPS), members of the toll-like receptors (TLR) and family peroxisome proliferator-activated receptors (PPARs) families, NF?B,and TNF-related weak inducer of apoptosis (TWEAK).
“Saturated fat ingestion rapidly increases hepatic lipid storage, energy metabolism, and insulin resistance. This is accompanied by regulation of hepatic gene expression and signaling that may contribute
to development of NAFLD,”
the researchers concluded.
Hernández EÁ, Kahl S, Seelig A, etal. Acute dietary fat intake initiates alterations in energy metabolism
and insulin resistance [published online January 23, 2017]. J Clin