SUO 2018: Fasting Regimens and Metabolic Health

Phoenix, Arizona (  There are numerous fasting regimens out there, Dr. Ruth Patterson's research and reviews distill them down to the following 4 that may have an impact on health outcomes. These include alternate-day fasting, modified fasting regimes, time-restricted feeding, and religious fasting.

SUO 2018 patterson fasting regimens

Most of the talks will focused on the middle two. The first is hard to implement and difficult to adhere to, so there is not much work being done with it. The last is sporadic and inconsistent. As such, the two in the middle (TRF and modified fasting regimens) are the two main ones being focused on. Specifically, TRF has gained the most momentum and interest.

In her 2017 Annual review of small trials (<100 patients) of fasting regimens, she identified 15 studies. Unfortunately, the variability in size, patient population, regimens, durations, definitions, and lack of control groups (in ~50% of studies) makes it hard to draw any real conclusions from these studies.

In contrast, there have been 3 large scale trials (>100 patients) in this space, two of which published just this year. They are summarized below:

SUO 2018 patterson fasting regimen trials

They all had better follow-up and more consistent regimens, and found moderate weight loss across the groups. They all concluded that there was no significant difference in weight loss or lipid changes when compared to “normal dieting methods.”

She then spent some time talking about TRF as a concept. There are many concepts for how TRF works, though none can claim to understand it completely. Below is a diagram of the interplay between central & peripheral circadian rhythms, and their potential interaction with gut diversity and activity, diet, sleep and physical activity – all of which may contribute to modifications of inflammatory, insulin and lipid metabolism pathways, leading to the effects seen on chronic diseases. Yet, the details of the interplay are not clear!

SUO 2018 patterson health mechanisms

The animal data is stronger than the epidemiologic data. The animal data will be discussed in the next talk.

Her take-home points:
1) Limited data from human studies to support rodent data regarding the impact of TRF vs. habitual diet on health
2) Human data are lacking regarding the impacts of TRF on diet, sleep and physical activity
3) Virtually no data linking TRF with human clinical outcomes such as diabetes, CVD and cancer

Presented by: Ruth Patterson, PhD, Department of Family and Preventive Medicine, University of California San Diego, San Diego, California

Written by: Thenappan Chandrasekar, MD, Clinical Instructor, Thomas Jefferson University, Philadelphia, Pennsylvania. twitter: @tchandra_uromd at the 19th Annual Meeting of the Society of Urologic Oncology (SUO), November 28-30, 2018 –Phoenix, Arizona