According to researchers from the University of Sydney, belly fat goes into “preservation mode” during intermittent fasting, adapting over time and becoming more resistant to weight loss.
"While most people would think that all fat tissue is the same, in fact, the location makes a big difference," said Mark Larance, senior author of the paper published in Cell Reports today. "Our data show both visceral and subcutaneous fat undergo dramatic changes during intermittent fasting."
During fasting, fat tissue provides energy to the rest of the body by releasing fatty acid molecules. However, the researchers found visceral fat became resistant to this release of fatty acids during fasting. There were also signs that visceral and subcutaneous fat increased their ability to store energy as fat, likely to rapidly rebuild the fat store before the next fasting period. Dr Larance said it was possible that a history of repeated fasting periods triggered a preservation signalling pathway in visceral fat.
"This suggests the visceral fat can adapt to repeated fasting bouts and protect its energy store," he explained. "This type of adaptation may be the reason why visceral fat can be resistant to weight loss after long periods of dieting."
Using mass spectrometry, the research team examined more than 8,500 proteins located in fat deposits, creating a catalog of changes that occurred during intermittent fasting. The results provide a rich source of data that helps to paint a more complete picture of the inner workings of fat tissue.