Chinese study claims no intermittent fasting advantage

[ras]

https://gizmodo.com/intermittent-fasting-not-better-than-regular-dieting-y-1848823438

[drewab]

 

[Dean Pomerleau]

As the above video discusses, time restricted eating works better for improving insulin/glucose when the eating window is early in the day, unlike the recent study where the eating was mid-day. Here is another recent Chinese relatively extended (5 week) study [1] comparing early and mid-day TRF for metabolic health in non-obese people. Here is the main figure showing the benefits of concentrating calories early in the day (eTRF):

The graphs show improved weight loss, insulin sensitivity, fasting blood glucose in the early TRF group, but not mid-day TRF group.

So if you are considering time restricted eating, it appears you should do it early in the day or not bother.

--Dean

-------------------------

1. Nat Commun. 2022 Feb 22;13(1):1003. doi: 10.1038/s41467-022-28662-5.

Randomized controlled trial for time-restricted eating in healthy volunteers 
without obesity.

Xie Z(#)(1), Sun Y(#)(2), Ye Y(#)(2)(3), Hu D(1)(4), Zhang H(5), He Z(2), Zhao 
H(1), Yang H(6), Mao Y(7).

Author information:
(1)Department of Liver Surgery, Peking Union Medical College (PUMC) Hospital, 
PUMC & Chinese Academy of Medical Sciences, Beijing, China.
(2)Peking Union Medical College (PUMC), PUMC & Chinese Academy of Medical 
Sciences, Beijing, China.
(3)Department of Head and Neck Surgery, National Cancer Center/National Clinical 
Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences 
and Peking Union Medical College, Beijing, China.
(4)Department of Hepatobiliary Surgery, Sun Yat-sen University Cancer Center, 
Guangzhou, Guangdong, China.
(5)Department of Vascular Surgery, Peking Union Medical College (PUMC) Hospital, 
PUMC & Chinese Academy of Medical Sciences, Beijing, China.
(6)Department of Liver Surgery, Peking Union Medical College (PUMC) Hospital, 
PUMC & Chinese Academy of Medical Sciences, Beijing, China. 
dolphinyahy@hotmail.com.
(7)Department of Liver Surgery, Peking Union Medical College (PUMC) Hospital, 
PUMC & Chinese Academy of Medical Sciences, Beijing, China. 
pumch-liver@hotmail.com.
(#)Contributed equally

Time-restricted feeding (TRF) improves metabolic health. Both early TRF (eTRF, 
food intake restricted to the early part of the day) and mid-day TRF (mTRF, food 
intake restricted to the middle of the day) have been shown to have metabolic 
benefits. However, the two regimens have yet to be thoroughly compared. We 
conducted a five-week randomized trial to compare the effects of the two TRF 
regimens in healthy individuals without obesity (ChiCTR2000029797). The trial 
has completed. Ninety participants were randomized to eTRF (n=30), mTRF (n=30), 
or control groups (n=30) using a computer-based random-number generator. 
Eighty-two participants completed the entire five-week trial and were analyzed 
(28 in eTRF, 26 in mTRF, 28 in control groups). The primary outcome was the 
change in insulin resistance. Researchers who assessed the outcomes were blinded 
to group assignment, but participants and care givers were not. Here we show 
that eTRF was more effective than mTRF at improving insulin sensitivity. 
Furthermore, eTRF, but not mTRF, improved fasting glucose, reduced total body 
mass and adiposity, ameliorated inflammation, and increased gut microbial 
diversity. No serious adverse events were reported during the trial. In 
conclusion, eTRF showed greater benefits for insulin resistance and related 
metabolic parameters compared with mTRF. Clinical Trial Registration URL: 
http://www.chictr.org.cn/showproj.aspx?proj=49406 .

© 2022. The Author(s).

DOI: 10.1038/s41467-022-28662-5
PMCID: PMC8864028
PMID: 35194047 [Indexed for MEDLINE]

Conflict of interest statement: The authors declare no competing interests.

[Gordo]

You should edit the title of this post to "no advantage to intermittent fasting with calorie restriction vs. calorie restriction alone for weight loss" as that was what was actually reported in the link.  Furthermore, its worth noting that while not statistically significant, the intermittant fasting group actually DID lose more weight on average: "Those who were intermittent fasting lost an average of 8 kilograms from baseline (about 17 pounds), compared to the 6.3 kilograms (just under 14 pounds) lost by the control dieting group—a difference that wasn’t statistically significant." 

But the real problem with "dieting studies" is that nobody actually follows the guidelines making them all pretty questionable.  If anyone from this obese group actually followed the guidelines, they wouldn't have lost 14 lbs in a full YEAR they probably would have lost >50 lbs.

[Clinton]

23 hours ago, Gordo said:

You should edit the title of this post to "no advantage to intermittent fasting with calorie restriction vs. calorie restriction alone for weight loss" as that was what was actually reported in the link. 

Exactly - thanks Gordo.

And perhaps it should also state 'for weight loss alone but not all benefits'. 

This study only looked at weight loss and not other (imo very significant) improvements that might increase healthspan/lifespan. 

I.E. Even IF there was ZERO change in fat loss - check out these benefits from Rhonda Patrick interview w Tim Ferriss (studies done on HUMANS):

Recent studies suggest that…
• Eating within an 11-hour window was associated with a decreased breast cancer risk and reduction in recurrence by as
much as 36%.
• Earlier meal timing associates with improved effectiveness of weight-loss therapy in overweight and obese patients.
• For each 3-hour increase in nighttime fasting duration was linked to a 20% lower odds of elevated glycated hemoglobin
(HbA1C), which is a more long-term marker of blood glucose levels.
• For each 10% increase in the proportion of calories consumed after 5pm there was a 3% increase in the inflammatory
biomarker c-reactive protein otherwise known as CRP.
• Eating one additional meal during the day (instead of the evening) was associated with an 8% decrease in CRP.
• Eating within a 12-hour window improved sleep and increased weight loss in normal weight people.

[Judy Reneau]

Once I retired from my job, I could eat when I wanted. My happiest eating times are 9 a.m., 12 noon, and 3 p.m. dinner w/red wine. During the evening I have vodka and 8 almonds. This is not scientific, just what makes my body happy.