New Research Shows that Intermittent Fasting Benefits the Liver


Intermittent fasting has become a dietary lifestyle that some patients choose, as well as a dietary treatment intervention that some integrative practitioners recommend. New research shows that intermittent fasting can be beneficial in the treatment of fatty liver disease, specifically non-alcoholic steatohepatitis (NASH).

An in vitro study published in Cell Metabolism found that the 5:2 intermittent fasting diet helped prevent and improve NASH while also reducing the risk of its transition into liver cancer. Specifically, from a mechanistic standpoint, the researchers found that PCK1 overexpression is reduced during fasting, leading to less fat accumulation in the liver. Through proteome, transcriptome, and metabolome analysis, the researchers found that PPARα and glucocorticoid-signaling-induced PCK1 work together in response to fasting to benefit liver health.

A systematic review and meta-analysis published last year in Hepatology Communications concluded that moderate- to high-quality evidence indicates intermittent fasting can improve weight loss and liver endpoints in adults with non-alcoholic fatty liver disease (NAFLD). That analysis looked at 14 studies that included 5:2, alternate-day fasting, time-restricted eating, and religious fasting.

Examples of the most common intermittent fasting regimens include:

  • 5:2 = two days a week eating limited calories, typically 500 or less; eating normally the other five days
  • Alternate day = low calories consumed every other day
  • Time-restricted feeding = also known as overnight fasting this type of fast is every day featuring a fasting window of about 14 hours; however, the range can be anywhere from 12 to 18 hours.

“The 5:2 intermittent fasting option is an acceptable alternative to time-restricted feeding because it is not too onerous for people to pick two days, not to fast, but just eat lightly,” explained integrative medical expert Ronald Hoffman, MD. “The lightened metabolic load enables clean up and repair.”

Dr. Hoffman explained that some pharmaceuticals such as pemafibrate were created to mirror fasting in cases of NAFLD/NASH.

“Pemafibrate fell short of mirroring fasting, and in humans, fibrate drugs are generally poorly tolerated," explained Dr. Hoffman, who was a recent guest on the Natural Medicine Journal Podcast talking about the latest research associated with intermittent fasting. “What’s clear is that dietary interventions so far outperform all drugs heretofore tested despite a push from drug makers to devise a pharmaceutical fix for what is essentially a lifestyle disorder.”

Mechanistically, Dr. Hoffman said intermittent fasting makes sense when it comes to enhancing liver function.

“Liver rest that lasts for hours can help reboot detoxification and repair pathways in this organ that is often overburdened by prolonged exposure to calories and highly processed foods,” concluded Dr. Hoffman.