Intermittent fasting · 8-hour window · Guangzhou
The closed kitchen sat on the same scale.
Nanfang locked one kitchen at 4pm for a year. Both scales dropped. The gap missed.
An 8-hour door from 8am to 4pm did not beat an open calorie plate over 12 months in Guangzhou.
The locked door weighed the same as the kitchen that stayed open.
Week 17 still wanted a magic window
The reel sold a clock. Nanfang sold a plate.
On 7 August 2026, r/intermittentfasting put up "Intermittent fasting week 17" and the thread sat at 709 points with 52 comments by the time last30days counted it.
People wanted a before picture.
A twin post on 27 July in r/caloriedeficit sat at 1,003 points, and a comment with 39 upvotes said an 18-hour empty gut felt light and free, which is a feeling this 12-month sheet never scored.
On 6 August, r/fatlogic asked if the window was fine for women, 227 points and 162 comments, because TikTok had already told them the stairmill plus a skipped breakfast would wreck cortisol.
YouTube already sells both sides of that clock. Cynthia Thurlow's TEDx talk "Intermittent Fasting: Transformational Technique" sits at 15,906,942 views, and Doctor Mike's diet review sits at 5,652,884.
A clip titled "Intermittent Fasting Doubles Your Risk of Dying from a Heart Attack" sits at 2,334,292, which is a scare caption sitting next to a different observational abstract.
On 12 August 2026 a Huberman Lab clip told 4,126 viewers the window is a calorie-control tool, not a magic diet. I wanted the year-long sheet that tested that sentence.
Nanfang ate lunch and locked the door at four
They ate breakfast. They closed the kitchen at 4pm.
Liu's Nanfang Hospital group printed the window in the New England Journal of Medicine, volume 386, issue 16, pages 1495 to 1504, DOI 10.1056/NEJMoa2114833, after a 12-month randomized room in Guangzhou.
Nanfang Hospital sits on 1838 North Guangzhou Avenue, and the work ran under the hospital board after every volunteer signed.
They recruited with leaflets and community screens between 30 November 2018 and 28 July 2021, then assigned 139 people with a BMI between 28 and 45, 69 to the 8-hour door and 70 to daily calorie restriction with no clock.
Young room.
Mean age sat at 31.9 with a spread of 9.1, and mean weight sat at 88.2 with a spread of 11.6, while the 8-hour arm started at 88.4 kilograms against 87.9 on the open plate.
Men were told to eat 1500 to 1800 kcal a day. Women were told to eat 1200 to 1500.
Both plates used the same mix, about 75 percent of what they had been eating, and both arms got one Nutriease protein shake a day for the first 6 months plus a coach for the whole year.
The 8-hour arm had to swallow those calories between 8am and 4pm. Water and other noncaloric drinks were allowed after the lock.
The open arm ate the same calorie target with no clock on the door.
That is a breakfast-and-lunch window, so the popular skip-breakfast 12-to-8 reel is a different door.
Their usual eating window already sat near 10 hours 23 minutes on the 8-hour arm and 10 hours 24 minutes on the open arm, so the lock shortened a day that was already fairly tight.
Coaches called twice a week for 6 months, then once a week, and two researchers scored the photos and the logs against the Chinese Food Composition Table.
They were told to keep their usual movement. The observers who weighed them did not know the assignment.
One hundred eighteen people, 84.9 percent, still showed up at month 12. Adherence to the assigned diet sat at 84.0 percent, spread 16.1, on the locked door against 83.8, spread 12.6, on the open plate.
Month twelve missed the 2.5 they powered for
The year treated both kitchens the same.
They powered the room to catch a 2.5 kilogram gap.
Month 12 put the locked door at minus 8.0 kilograms, 95 percent CI minus 9.6 to minus 6.4, while the open plate sat at minus 6.3, 95 percent CI minus 7.8 to minus 4.7, for a net of minus 1.8, 95 percent CI minus 4.0 to plus 0.4, p = 0.11.
The gap they came to catch stayed inside the noise.
Month 6 had already sat close, minus 9.4 against minus 8.9, net minus 0.5.
More than 5 percent down sat at 61 percent on the locked door against 60 on the open plate, and more than 10 percent down sat at 39 against 41.
The DXA followed the kilogram
The scanner followed the kilogram down.
A Lunar iDXA printed body fat at month 12 as minus 5.9 kilograms on the locked door, 95 percent CI minus 7.1 to minus 4.7, against minus 4.5, 95 percent CI minus 5.6 to minus 3.3, on the open plate.
Lean mass dropped on both arms, minus 1.7 against minus 1.4.
Waist lost 8.8 centimeters against 7.0, and BMI lost 2.9 against 2.3.
Systolic pressure dropped 8.1 mm Hg against 7.7 while diastolic dropped 5.1 against 3.8.
The fasting sugar sat with the 2-hour draw. HOMA-IR and the lipid panel sat in the same band.
No death printed. Mild events sat on both arms in similar counts, and no serious event printed.
The authors named the holes. The room was young and Chinese and free of diabetes, so a 12-to-8 skip-breakfast reel in another country is a different door, and they never ran doubly labeled water, and they left movement free on purpose.
I keep the other clock files in the Library.
The plate still has to match.
If you came here for intermittent fasting, Nanfang measured an 8am-to-4pm door against an open calorie plate, then weighed both kitchens at month 12.
Write the calories if you want that year, because a locked door on an unmatched plate is a different trial.
This page is about the 4pm lock that sat on the same scale, so run Protocol 01 first if you want a short daily count.
Questions the 4pm lock left open
Is this the skip-breakfast 16:8 I keep seeing?
They ate from 8am to 4pm, so breakfast stayed in and dinner went out.
Liu even named a 116-person 12-to-8 room by Lowe that also failed to beat an open plate when calories stayed free.
What about the heart-attack reel?
That 2.3 million-view caption sits on a different observational abstract. This file is a 12-month randomized room with no death and no serious event.
Did they print a women's cortisol sheet?
No cortisol table printed in the main paper. Sex sat near even, 36 men and 33 women on the locked door, and the subgroup line said the kilogram moved the same by sex.
Who paid?
The National Key Research and Development Project grant 2018YFA0800404 plus later Nanfang and Guangdong grants. Nutriease supplied the first-6-month shake on both arms.
Can I graze if I shut the door at 4?
This sheet matched the calories on purpose. The authors wrote that the calorie cut explained most of what the window did.
Nanfang's 12-month sheet
Liu D., Huang Y., Huang C., Yang S., Wei X., Zhang P., Guo D., Lin J., Xu B., Li C., He H., He J., Liu S., Shi L., Xue Y., Zhang H. "Calorie Restriction with or without Time-Restricted Eating in Weight Loss." New England Journal of Medicine 2022, 386(16), 1495 to 1504. DOI 10.1056/NEJMoa2114833. PMID 35443107. ClinicalTrials.gov NCT03745612. Nanfang Hospital, Southern Medical University, Department of Endocrinology and Metabolism, 1838 North Guangzhou Ave., Guangzhou 510515, plus Tulane epidemiology. Randomized 12-month parallel trial. Board at Nanfang Hospital. Written consent. Recruited 30 November 2018 through 28 July 2021 from leaflets, posters, internet, community screens. Eligible age 18 to 75, BMI 28 to 45. Exclusions included viral hepatitis, cancer, diabetes, serious liver or kidney disease, current smoking, recent serious heart or brain events, recent gut surgery, an active weight-loss program, weight-changing drugs, pregnancy. Assigned n=139, TRE 69, daily calorie restriction 70. Completed 6 months 135 (97.1 percent). Completed 12 months 118 (84.9 percent). Mean age 31.9 SD 9.1. Mean weight 88.2 SD 11.6. Table 1 TRE / DCR: male 36 (52.2 percent) / 35 (50.0). Age 31.6 SD 9.3 / 32.2 SD 8.8. Weight 88.4 SD 10.2 / 87.9 SD 12.8. BMI 31.8 SD 2.9 / 31.3 SD 2.6. Fat mass 33.0 SD 7.3 / 33.2 SD 6.3. Lean 51.2 SD 7.8 / 50.9 SD 9.1. Fat percent 38.3 SD 5.5 / 38.4 SD 5.3. Waist 99.4 SD 7.8 / 99.2 SD 9.1. Systolic 125.3 SD 12.0 / 124.8 SD 12.2. Diastolic 73.1 SD 9.5 / 74.5 SD 9.6. Baseline kcal 2052.5 SD 341.7 / 2075.7 SD 391.5. Daily eating window 10:23 SD 01:25 / 10:24 SD 01:34. Men 1500 to 1800 kcal, women 1200 to 1500, about 75 percent of baseline, carbs 40 to 55 percent, protein 15 to 20, fat 20 to 30. TRE ate 8:00 a.m. to 4:00 p.m. DCR ate the same calories with no clock. One Nutriease shake daily for 6 months on both arms. Coaches, photo logs, Chinese Food Composition Table. Movement left free. Observers unaware of assignment. Adherence 84.0 SD 16.1 percent vs 83.8 SD 12.6. Powered for 2.5 kg at greater than 90 percent, target 138, two-tailed 0.025. Mixed-effects model, multiple imputation. Table 2 weight 6 mo -9.4 (-10.8 to -7.9) vs -8.9 (-10.3 to -7.4), net -0.5 (-2.6 to 1.6). 12 mo -8.0 (-9.6 to -6.4) vs -6.3 (-7.8 to -4.7), net -1.8 (-4.0 to 0.4), p=0.11. BMI 12 mo -2.9 vs -2.3, net -0.7. Waist 12 mo -8.8 vs -7.0, net -1.8. Fat mass 12 mo -5.9 vs -4.5, net -1.5. Lean 12 mo -1.7 vs -1.4, net -0.3. Fat percent 12 mo -4.3 vs -3.0. Visceral fat 12 mo -26.0 vs -21.1 cm2. Subcutaneous 12 mo -53.2 vs -37.0. Figure 1 more than 5 percent 61 vs 60, more than 10 percent 39 vs 41, more than 15 percent 17 vs 11. Table 3 systolic 12 mo -8.1 vs -7.7. Diastolic -5.1 vs -3.8. Pulse -1.6 vs -1.9. Triglycerides -25.5 vs -19.6. Total cholesterol -7.3 vs -9.3. HDL +4.6 vs +2.9. LDL -8.4 vs -8.9. Glucose -3.5 vs -3.0. 2-hour glucose -10.8 vs -12.1. HOMA-IR -1.0 vs -0.5. No deaths, no serious events. Limitations named: not diabetes or cardiovascular disease, not other windows, not other races, no doubly labeled water, movement not controlled. Funded by National Key Research and Development Project 2018YFA0800404 and others. doi.org/10.1056/NEJMoa2114833 · pubmed.ncbi.nlm.nih.gov/35443107 · clinicaltrials.gov/study/NCT03745612
Lowe D.A., Wu N., Rohdin-Bibby L., et al. "Effects of time-restricted eating on weight loss and other metabolic parameters in women and men with overweight and obesity: the TREAT randomized clinical trial." JAMA Internal Medicine 2020, 180, 1491 to 1499. The 116-person 12:00 p.m. to 8:00 p.m. room Liu named, similar to ad libitum intake. doi.org/10.1001/jamainternmed.2020.4153