Time restricted eating- a Systematic Review

*This article is written so that everyone can understand it. However, the content itself may be considered scientifically technical.

Time restricted eating is an eating strategy that has been gaining popularity in the past decade. In the early 2010’s animal studies showed health benefits for the animals, and the following human studies showed benefits to human health too.

Basically, what Time Restricted Eating entails is eating all of your daily food within a time window. For example, once you take your first bite of food in the morning, you may limit yourself to eat the remainder of your daily food within 12, 10, or even 8 hours of that first bite.

I have been following this health strategy on-and-off for a few years now, and I do recommend it to some of my patients if it may help them achieve their health goals. But… why might you choose to eat using this method?

The following is from a systematic review of the scientific literature on this topic. Since systematic reviews are considered the best for research methods quality, we know the following to be trustworthy information on the topic.

Adafer R, Messaadi W, Meddahi M, Patey A, Haderbache A, Bayen S, Messaadi N. Food Timing, Circadian Rhythm and Chrononutrition: A Systematic Review of Time-Restricted Eating’s Effects on Human Health. Nutrients. 2020; 12(12):3770. https://doi.org/10.3390/nu12123770

You can find the full article here: https://www.mdpi.com/2072-6643/12/12/3770?fbclid=IwAR396M4jXltQZY3w-boq_Rr3vgai-UK7HKvoiPmKoOMOBpk_HwDwI_uKWG8

So what are the findings of this review, and what are the health benefits we can gain from time restricted eating???

1) Adherence- 80% of people followed through with time restricted eating. This means that it is a relatively easy thing to do!

2) Calorie intake- on average, people ate 20% less calories while not altering the amount of their eaten macronutrients. This was a happy accident :)

3) Circadian clock- time restricted eating affected the expression of 6 genes related to our daily hormone cycles, and it was found that people’s sleep quality improved because of this.

4) Metabolic effects of reduced eaten food- weight loss, reduced fat mass, reduced blood sugar, reduced blood pressure, reduced blood cholesterol, reduced waist circumference.

5) Metabolic effects without reduced eaten calories- reduced blood sugar, reduced insulin resistance, better blood sugar control, reduced blood triglycerides (fat), reduced fat mass, increased HDL “good” cholesterol, reduced blood pressure.

6) Other health effects- a number of other blood markers of better health and longevity were found in people who practiced time restricted eating. They are a little complicated to write and explain here. You can read the article if you are interested in these details :)

*In summary- Time restricted eating is a simple and well tolerated strategy for calorie restriction. Time restricted eating is different from other dietary interventions by producing benefits on many health markers regardless of calorie intake changes.

As always, if you have health goals that you are working towards and you think that trying time restricted eating may be worthwhile- you can always ask a health care provider for more details about it. I would recommend speaking with a registered dietician, or a well informed professional such as your Chiropractor or family physician.