Dr. Satchin Panda on Practical Implementation of Time-Restricted Eating & Shift Work Strategies
2 hour interview with Dr. Rhonda Patrick (FoundMyFitness) on YouTube
Key points from interview (though I recommend watching it in full):
Animals show range of improvements with time restricted eating, even if fed a poor diet they still have improved markers of metabolism.
Favorable effects on inflammation and insulin resistance only seen when stopped eating before 6pm - not if skipped breakfast.
Relative risk of night time eating = 1.5 compared those who don't.
Effect on metabolic syndrome won't be known for 5-7 years when clinical trials report.
Time restriction tends to reduce calories as a side-effect (even if not told to reduce).
Definition of being healthy varies throughout the day - want to start with energy, during the day shouldn't be hungry, at night time should be sleepy.
Should not have food for 2-3 hours before going to bed.
By the time you wake up, should have done 10-14 hours of fasting - with no food in system (all been metabolised).
If have food in system at night - blood redirected to stomach so core temperature remains high.
Aim for 10-12 hour max of eating window.
- Time restricted eating = humans
- Time restricted feeding = animals
Easier to manage time rather than number of calories.
2 days of binge eating didn't destroy all benefit (in mice) - hopefully 1-2 times a week in humans will be OK.
People often feel hungry initially - reduced with high fat or fibre or protein diet - reduces after 2-3 weeks.
People diligent for a few weeks, but if have lapse after 5-6 weeks then really notice tiredness.
People report that immune-related diseases improve with TRE, e.g. number of time people with IBS go to the bathroom reduces.
TRE may reduce gut leakiness as has more time at night to repair itself.
Gut microbiome changes with circadian rhythm. Diversity reduces when on unrestricted eating.
Shift work (and even families of shift workers - or second hand shift workers) has a major impact on cardiovascular disease. Around 30-40% of American workers fit in this category.
TRE still beneficial even if feeding nocturnal animals during the day.
Most CR studies feed mice during day - but generally consumed within hours so time restricted.
Insulin sensitivity at its best in the morning, but don't know if that gets delayed if don't eat until lunchtime.
Melatonin levels rise 2-3 hours before going to bed.
Melatonin can bind to receptor in pancreas - prevents release of insulin to counter blood sugar spikes.
Better to restrict eating to 8 hours, even if starting late, rather than eating for 12-15 hours/day.
First food triggers starts some liver enzymes and rhythms.
Insulin response worse in evening - could be diagnosed if checked against evening meal.
SP doesn't regard TRE as fasting.
Fasting more like over 24 hours - which triggers ketone bodies to be generated.
SP does 4-5 days of water fasting once a year.
Multi-day fasting has been shown to have benefits in multiple studies.
Autophagy follows a circadian cycle - increases during fasting phase.
Circadian cycle has a big impact on DNA damage and repair.
Rarely get cancer in hair follicles which are rapidly dividing - which have strong repair mechanism at end of the day. Hair quality of mice declines massively if irradiated in morning instead of evening.
Caffeine resets liver's clock but doesn't affect the circadian clock.
Murky as to whether caffeine triggers end of fast - so safer to only drink within TRE window. Some studies allow coffee/tea consumption as fasting.
Polyphenols in coffee (including decaffeinated) may trigger autophagy.
May need to self experiment to see if plant extracts, supplements or even flavoured water kick off your metabolism - affects can be very personal.
Cleaning teeth doesn't end a fast.
Checked whether athletic performance may go down with TRE - in mice, grip strength remained the same and endurance increased (up to double). Personal accounts also reported.
Longer fasting periods results in higher levels of ketone bodies.
TRE mice on normal diet (8-9 hour window) had increased lean muscle mass - possibly due to increased PGC-1a activity.
A good size snack will trigger an insulin response for 90-120 minutes.
Smaller number of meals is better - but don't have proper data yet.
Breakfast with plenty of protein should keep hunger at bay for 8 hours.
Circadian rhythm affects medication affect - some drug targets have peaks at different times of the day, which could allow reduced doses (and therefore reduced side-effects).
Blue light is responsible for entraining the body to a 24-hour cycle.
Brain age of long-term shift workers 6 years older.
MyCircadianClock.org - new version coming which is more user friendly.
- Should baseline for a couple of weeks with existing lifestyle.
- Should run for at least 12 weeks with one time window.
- Minimum submission is first and last meal.
Visit website: https://www.youtube.com/watch?v=iywhaz5z0qs
See also: FoundMyFitness - Promoting strategies to increase healthspan, well-being, cognitive and physical performance
Mentioned in this Resource
CEO and Co-founder at FoundMyFitness, Ph.D in biomedical science/expert on nutritional health, brain and aging
Professor at Salk Institute.