I predict that intermittent fasting will soon become mainstream. While I’m sure many of you already know about it, outside of our health and fitness bubble, the majority of people don’t. But it’s only a matter of time before the public has some idea of it. And when it happens, there’ll be many versions of it to choose from. In the meantime, let’s cover one form of it known as Time-Restricted Eating. I’ll give you the 101 and benefits to help you decide if it’s worth trying. Are you ready? Then let’s go! 

Time-Restricted Eating 101

First, let’s do an ultra-quick summary of intermittent fasting. Intermittent fasting (or, IF) is when you alternate between eating and fasting (aka, not eating). An example of IF is skipping breakfast and only eating lunch, dinner, and the optional snack or dessert (although it’s recommended to stick to your main meals). OK, now let’s switch over to Time-Restricted Eating (TRE).

Unlike IF where you can skip a meal or choose to fast whenever you’d like it, TRE is very specific about when you’re supposed to eat. When doing TRE, you’re only allowed to eat within a window of time before fasting. The eating window lasts between 6-12 hours a day, with the remaining hours going towards fasting. Many experts recommend opting for a minimum of 12 hours of fasting. [1]

 The Benefits

What makes TRE so effective, you may ask?

It Manages Calories 

For one, it allows you to eat without restricting calories. Unlike fad diets that have you cut back on calories, TRE doesn’t involve counting a single one. While I’m not a fan of managing your calories, you can technically over or under eat on TRE and still follow it. It’s really about when you eat, not how much or even what you should eat. However, most people naturally reduce their calories when following TRE. Early studies show that TRE causes adults to eat fewer calories per day, some showing as much as 20% and others by about 650 calories. [2] [3]

 Although this is promising, I need to be fair and point out that there’s other research to show that TRE doesn’t cause much of a change in calorie intake. Experts point out that a big flaw in these studies is that they’re based on personal diet records made by the subjects and not a supervisor. Diet records are notorious for being inaccurate, with some people overestimating and others underestimating. So, we cannot completely rely on self-reporting. [4] [5]

Balancing Blood Sugar

Secondly, it balances blood sugar. How? By eating within a shorter eating window, you start to realign with what’s known as your circadian rhythms. It’s like an internal “alarm clock” that helps to regulate your sleep and “wake” cycles, hormones, and hunger. Insulin levels are more active earlier in the day, which makes sense from an evolutionary point of view when our ancestors hunted and gathered outside. High insulin levels mean that nutrients are easier to use up for energy and not get stored (as fat) for later use. So, in theory, by syncing your eating window with the appropriate time when insulin levels are high, you can manage blood sugar and burn calories more efficiently.

Researchers from the University of Adelaide and the South Australian Health and Medical Research Institute (SAHMRI) explain that, “Time-restricted eating regimes demonstrate that we can enjoy foods that are perceived to be ‘bad’ for us, if we eat them at the right time of day, when our bodies are more biologically able to deal with the nutrient load. And perhaps more importantly, if we allow our bodies to have more time fasting each night. While these early results show some promise for controlling blood glucose (sugar), a larger study over a longer duration is required to fully investigate the effectiveness of this pattern of time-restricted eating.” [6]

Anti-Aging and Longevity

Third, TRE supports longevity, giving it a sort of “anti-aging” effect. According to Dr. Satchidananda Panda, professor and researcher at the Salk Institute for Biological Studies in La Jolla, California, and expert on TRE, “The science and the benefits of time-restricted eating are very different from those of other forms of fasting. It works by slightly reducing ATP producing proteins of mitochondria in the heart and keeping the mitochondria healthy, which reduces oxidative stress. Most of our studies are showing that the effect is on multiple organs and on the central nervous system. It’s a positive feedback loop.” [7]

Translation? It allows the body a chance to go into repair mode and heal. A sort of “reset,” if you want to look at it that way! This “reset” or “cleanse” is what’s known as autophagy which literally translates into “self-eating.” Now, don’t get scared! Your body is not eating itself away. What it’s doing is clearing away garbage like old, broken, or infected cells that build up over time and lead to degenerative diseases like Alzheimer’s. [8] It also reduces inflammation, which is another driver of disease and premature aging. [9] Autophagy is right at the forefront of science and anti-aging research, so there’s still so much we have to understand about this essential process! Luckily though, one of the best ways to increase it is through fasting or time-restricted eating. Both human and animal studies are starting to pop up with the benefits to show, so let’s see what else we’ll discover in the future! For now, keep an eye on this space for exciting updates! [10]

Alright, everyone, I hope you enjoyed today’s post! I actually held back and gave you just a beginner’s understanding of TRE. If you’re interested in learning more, I recommend checking out Dr. Rhonda Patrick, who is a frequent guest on the Joe Rogan show.

For the technical details and science of TRE, check out her website here (which provides all of the research). She also interviewed TRE expert Dr. Panda for her podcast (watch it here); warning, it gets very complicated! For a more straightforward explanation, check out her segment on TRE with Joe Rogan here.

Sources:

[1] https://www.medicalnewstoday.com/articles/322365.php
[2] https://www.ncbi.nlm.nih.gov/pubmed/9363296
[3] https://www.ncbi.nlm.nih.gov/pubmed/27550719
[4] https://www.ncbi.nlm.nih.gov/pubmed/8599311
[5] https://nutritionj.biomedcentral.com/articles/10.1186/1475-2891-11-69
[6] https://www.sciencedaily.com/releases/2019/04/190424153634.htm
[7] https://www.heart.org/en/news/2019/03/22/time-restricted-eating-is-growing-in-popularity-but-is-it-healthy
[8] https://www.cell.com/trends/neurosciences/fulltext/S0166-2236%2814%2900158-1
[9] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5529308/https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5529308/
[10] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5388543/