Time-restricted eating and cancer: lessons learned and considerations for a path forward.

Time-restricted eating is a type of intermittent fasting. Food can be consumed as desired during the eating period but not during the remainder of the day. Studies suggest that many of the health benefits of fasting may not simply be the result of weight loss but also due to the body's responses to the fasting that leads to improved metabolic functioning. Whereas animal studies are convincing regarding the benefits of time-restricted feeding, human time-restricted eating studies are less consistent and generally short term (<1 year). In 2020, the National Cancer Institute funded 5 intermittent fasting studies, 4 of which focused on time-restricted eating, which addressed the question: How does intermittent fasting affect cancer incidence, treatment response, or outcome? The National Cancer Institute sponsored a webinar in 2023 featuring investigators of the funded studies in which they discussed challenges as well as their thoughts regarding the most important time-restricted eating topics that should be addressed going forward; 6 areas were identified, which are discussed below as well as in a recently published NOT-CA-24-073: Factors Impacting How Time-Restricted Eating (TRE) Influences Cancer-Related Outcomes. Moving the science forward will allow the scientific community to better understand time-restricted eating's potential. This potential includes the development of targeted time-restricted eating interventions to optimize long-term adherence to the intervention, which is required to better understand its potential benefits in cancer risk and increased response to cancer treatment, as well as improved quality and quantity of life among cancer survivors.