Chrononutrition and Early Time-Restricted Eating for Metabolic Health

July 24, 2020

Before it became so easy for us to stay up at night, cross time zones in a single afternoon, and eat at any time of the day, humans were inclined to live in accordance with natural light/dark cycles. It’s probably no accident that along with these lifestyle changes we’ve entered an era marked by chronic illness - the so-called mismatch diseases. Metabolic disorders are often attributed to eating too much or consuming the wrong kinds of food. But fascinating research from just the last several years suggests we’re also eating at the wrong time of the day.

With me today on the podcast is writer, speaker, and researcher Greg Potter, PhD. to talk about chrononutrition - how the foods we eat and the times we eat them impact our inner clocks and metabolic health. Greg discusses how changing when you eat can have profound effects, including reduced blood glucose, insulin, and appetite, and even better outcomes with COVID-19. He breaks down specific macronutrients to eat, when to eat them, and in what order, to optimise the body’s inner timekeeper. 

If you enjoy this podcast, be sure to read Greg’s articles on chrononutrition over at HumanOS: Part 1, Part 2, and Part 3.

Here’s the outline of this interview with Greg Potter:

[00:00:12] Metagenics Institute Podcast with Nathan Rose. 

[00:03:24] Early time-restricted eating (eTRE).

[00:04:18] A review of the circadian system.

[00:06:41] Consuming food earlier in the day leads to lower postprandial glucose and insulin; Meta analysis: Leung, Gloria KW, et al. "Time of day difference in postprandial glucose and insulin responses: Systematic review and meta-analysis of acute postprandial studies." Chronobiology International 37.3 (2020): 311-326.

[00:06:58] Time of day changes in immune function; Study: Abele, Sydney H., et al. "Focus: Clocks and Cycles: Time is on the Immune System’s Side, Yes it is." The Yale journal of biology and medicine 92.2 (2019): 225.

[00:10:51] How changing food timing can affect your health.

[00:12:34] TRE associated with better health outcomes; Study: Gill, Shubhroz, et al. "Time-restricted feeding attenuates age-related cardiac decline in Drosophila." Science 347.6227 (2015): 1265-1269.

[00:13:15] Satchin Panda; Podcast: How to Use Time-Restricted Eating to Reverse Disease and Optimize Health.

[00:13:23] High-fat diet leads to changes in circadian rhythm in mice; Study: Eckel-Mahan, Kristin L., et al. "Reprogramming of the circadian clock by nutritional challenge." Cell 155.7 (2013): 1464-1478.

[00:16:03] Definitions - TRE vs IF (intermittent fasting).

[00:17:00] Different types of fasting: Alternate Day Fasting, Modified ADF, 5:2 Diet, Modified 5:2, nutrient restriction.

[00:18:30] Fasting Mimicking Diet.

[00:21:27] Intermountain Risk Score and calculator; Changes in blood chemistry with fasting.

[00:22:19] Time of day and macronutrient intake.

[00:22:34] Eating earlier in the day beneficial for metabolic health; Study: Jakubowicz, Daniela, et al. "High caloric intake at breakfast vs. dinner differentially influences weight loss of overweight and obese women." Obesity 21.12 (2013): 2504-2512.

[00:23:40] Three meals and a big breakfast better than 6 small meals; Study: Jakubowicz, Daniela, et al. "Reduction in glycated hemoglobin and daily insulin dose alongside circadian clock upregulation in patients with type 2 diabetes consuming a three-meal diet: a randomized clinical trial." Diabetes Care 42.12 (2019): 2171-2180.

[00:25:34] Eat your carbs last; Study: Shukla, Alpana P., et al. "Food order has a significant impact on postprandial glucose and insulin levels." Diabetes care 38.7 (2015): e98-e99.

[00:32:11] Possible genetic impact on circadian system; Study: Lopez-Minguez, Jesus, et al. "Circadian system heritability as assessed by wrist temperature: a twin study." Chronobiology international 32.1 (2015): 71-80.

[00:38:59] Early TRE better but perceived as more difficult; Study: Parr, Evelyn B., et al. "A delayed morning and earlier evening time-restricted feeding protocol for improving glycemic control and dietary adherence in men with overweight/obesity: a randomized controlled trial." Nutrients 12.2 (2020): 505.

[00:41:53] Early TRE improves metabolic markers and reduces appetite; Study: Sutton, Elizabeth F., et al. "Early time-restricted feeding improves insulin sensitivity, blood pressure, and oxidative stress even without weight loss in men with prediabetes." Cell metabolism 27.6 (2018): 1212-1221.

[00:48:23] Diet timing and COVID-19 mortality; Study: Verd, Sergio, et al. "Early dinner or “dinner like a pauper”: Evidence, the habitual time of the largest meal of the day–dinner–is predisposing to severe COVID-19 outcome–death." Chronobiology International (2020): 1-5.

[00:53:51] Chris Kelly’s approach to circadian timing.

[00:57:14] How much protein to eat? 0.4g protein/Kg body mass of high-quality protein per dietary event.

[00:57:46] Digestible indispensable amino acid score.

[00:59:12] Podcast: Why You’re Probably Not Eating Enough Protein (How to Know for Sure), with Megan Hall.

[00:59:53] Resilient Nutrition (website coming soon).

[01:03:37] Resilient Nutrition on Instagram and Facebook.