Work in mice and humans suggests that the widely-used food preservative propionate (propionic acid) may impair the action of insulin, according to U.S. and Israeli researchers.
The short-chain fatty acid propionate, which has potent anti-mold effects, is generally recognized as being safe and is endogenously produced by gut microbiota, the researchers say.
But as reported online April 24 in Science Translational Medicine, Dr. Amir Tirosh of the Sheba Medical Center, Tel-Hashomer, and colleagues found that the agent stimulates glycogenolysis and hyperglycemia in mice by increasing plasma concentrations of glucagon and fatty acid-binding protein 4 (FABP4). FABP4-deficient mice and mice lacking liver glucagon receptor were protected from its effects.
In addition, compared to control mice, over the course of 20 weeks, mice given drinking water with concentrations of propionate similar to concentrations in preserved foods gained more weight and had higher insulin resistance.
In a double-blind, placebo-controlled crossover study in 14 “lean and healthy” human volunteers, adding a typical preservative amount of propionate to a mixed meal increased glucagon and FABP4 levels and raised insulin resistance.
Furthermore, examination of serum samples from 160 overweight and obese volunteers taking part in a 2-year dietary intervention trial showed that plasma propionate decreased with weight loss. A greater decline in serum propionate (from baseline to 6 months) was associated with a significant improvement in insulin resistance. This was the case regardless of the dietary intervention or initial body weight. It thus served as an independent predictor of improved insulin sensitivity.| | | Next → | Single Page