Table 2.

Effects of sodium acetate infusions in humans at different administration sites.

Dose	Primary Outcome	Subjects	Administration Site	Effects on Lipid/Glucose Metabolism	Study
SCFA infusion mixtures rich in acetate (24 mmol/L acetate, 8 mmol/L propionate, and 8 mmol/L butyrate) and propionate (18 mmol/L acetate, 14 mmol/L propionate, and 8 mmol/L butyrate)	Fat oxidation and energy expenditure	Overweight/obese men (n = 12)	Colonic infusions	Attenuation of whole-body lipolysis ↑ Fat oxidative capacity Fat oxidation and energy expenditure related to increments in fasting acetate ↑ Fasting and postprandial PYY No effects on insulin and glucose	Canfora et al. 2017 [120]
180 mmol/L sodium acetate	Fat oxidation and energy expenditure	Overweight/obese men (n = 6)	Proximal and distal colonic	↑ Fasting fat oxidation ↑ Postprandial glucose and insulin Tendency to decrease TNF-α ↑ Fasting peptide YY	Van der Beek et al. (2016) [39]
140 mmol/L in 90-min sodium acetate	Peripheral uptake	Overweight normoglycemic and hyperglycemic subjects (n = 9 vs. 9)	Intravenous	No difference in acetate clearance between individuals with normal (NI) and high (HI) insulin levels. ↑ FFA rebound in NI than HI.	Fernandes et al. (2012) [113]
60 mmol/L (rectal), 20 mmol/L (intravenous) sodium acetate	Gut derived hormone secretion	Hyperinsulinaemic females (n = 6)	Rectally and intravenous	in PYY/GLP-1 after rectal infusions and decrease in TNF	Freeland et al. (2010) [112]
12 mmol/L per hour	Hepatic glucose production	Healthy subjects (n = 6)	Intragastric	↓ Circulating FFA No effect on hepatic glucose production	Laurent et al. (1995) [20]
800 mL rectal infusions with 180 mmol/L	Glucose homeostasis	Healthy subjects (n = 6)	Rectal infusion	No effects on insulin and glucose ↓ Circulating FFA	Wolever et al. (1989) [118]

Abbreviations: SCFA, short chain fatty acids. PYY, peptide YY. GLP-1, glucagon like-peptide 1. TNF-α, Tumor necrosis factor. FFA, free fatty acid.