This is a stub. Most of this requires Zotero importing…
Posting on the Internet…
I’ve done a fair amount of spelunking through the metabolic research over the years, and frankly, the studies I’ve found on long-term (say >8wks) TRE (time restricted eating) in healthy individuals is pretty thin, so I’d recommend people to take everything people (even those passing on credentialed 2nd-hand advice) have to say skeptically because IMO 1) the “science” isn’t really isn’t there. (If your partner has DOI references or has observed evidence via labs or RQ testing, feel free to share, I’d love to hear about it) and 2) there’s so much bio-individuality that it’s dumb to make such broad statements, especially when the flip side is that there’s a fair number biohackers doing n=1 experiments w/ frequent labwork (Peter Attia et al), along with so much new research showing substantial short term health benefits from (especially) eTRF on such a wide range of cardio-metabolic markers.
Here btw are a few of the relevant studies I’m aware of for those interested…
doi: 10.1001/jamainternmed.2020.4153 - Effects of Time-Restricted Eating on Weight Loss and Other Metabolic Parameters in Women and Men With Overweight and Obesity - this was a recent (2020) UCSF 12wk n=116 study on overweight/obese individuals, but the interesting part is that body composition via DXA and metabolic rates via RQ were measured. In Supplement 3, eFigure 1 you can see that energy expenditure actually increased for the TRE group (while declining in the consistent meal timing group), which would seem to contradict the idea of lowered metabolism. (personally, I think that’s an iffy idea anyway anyway - your metabolism is going to be much more affected by muscle mass/mitochondrial function - both of which is driven by resistance exercise training, and on appropriate endocrine markers (low fasting insulin, proper thyroid and sex hormone levels)).
doi: 10.3390/nu14194216 - Intermittent Fasting—Short- and Long-Term Quality of Life, Fatigue, and Safety in Healthy Volunteers: A Prospective, Clinical Trial - this is a brand new (Oct 2022) study published, also 12wk, n=30 with healthy individuals. From labwork done (basically a CMP w/ some extras) no negative effects were observed, except IGF-1 was improved, as were QoL scores. The most interesting part of this study is that it’s one of the few using healthy individuals.
doi: 10.1249/MSS.0000000000002738 - this is longest study I know of (12 mo, n=34), although there are two other 12mo studies, NCT03533023 and NCT04465721 that should publish soon. Anyway, the abstract conclusion: “Our results suggest that long-term TRE combined with a resistance training program is feasible, safe, and effective in reducing inflammatory markers and risk factors related to cardiovascular and metabolic diseases.”
One thing to consider is that these are small studies and there is a huge amount of bio-individuality and a lot that we don’t understand about human metabolism (or health in general). My general approach is that everyone should try what they want - keep doing the things that work and where they feel good doing it. Stop doing it if it stops working or they don’t feel good doing it. If you like numbers, do the labs you want for yourself to help decide if it’s good for you (whether it’s just bloodwork, DXA, RQ, whatever). Almost all historical guidelines/nutritional advice has proven to be contingent, if not outright wrong/overturned over the past decades and it takes a long time (again, often decades) for new research to filter into scientific orthodoxy and then clinical practice, much less government guidelines…