The efficacy and safety of time-restricted eating have not been explored in large randomized clinical trials.
To determine the effect of 16:8-hour time-restricted eating on weight loss and metabolic ...risk markers.
Participants were randomized such that the consistent meal timing (CMT) group was instructed to eat 3 structured meals per day, and the time-restricted eating (TRE) group was instructed to eat ad libitum from 12:00 pm until 8:00 pm and completely abstain from caloric intake from 8:00 pm until 12:00 pm the following day.
This 12-week randomized clinical trial including men and women aged 18 to 64 years with a body mass index (BMI, calculated as weight in kilograms divided by height in meters squared) of 27 to 43 was conducted on a custom mobile study application. Participants received a Bluetooth scale. Participants lived anywhere in the United States, with a subset of 50 participants living near San Francisco, California, who underwent in-person testing.
The primary outcome was weight loss. Secondary outcomes from the in-person cohort included changes in weight, fat mass, lean mass, fasting insulin, fasting glucose, hemoglobin A1c levels, estimated energy intake, total energy expenditure, and resting energy expenditure.
Overall, 116 participants (mean SD age, 46.5 10.5 years; 70 60.3% men) were included in the study. There was a significant decrease in weight in the TRE (-0.94 kg; 95% CI, -1.68 to -0.20; P = .01), but no significant change in the CMT group (-0.68 kg; 95% CI, -1.41 to 0.05, P = .07) or between groups (-0.26 kg; 95% CI, -1.30 to 0.78; P = .63). In the in-person cohort (n = 25 TRE, n = 25 CMT), there was a significant within-group decrease in weight in the TRE group (-1.70 kg; 95% CI, -2.56 to -0.83; P < .001). There was also a significant difference in appendicular lean mass index between groups (-0.16 kg/m2; 95% CI, -0.27 to -0.05; P = .005). There were no significant changes in any of the other secondary outcomes within or between groups. There were no differences in estimated energy intake between groups.
Time-restricted eating, in the absence of other interventions, is not more effective in weight loss than eating throughout the day.
ClinicalTrials.gov Identifiers: NCT03393195 and NCT03637855.
Billy Idol Weiss, Ethan J
Perspectives in biology and medicine,
2020, Volume:
63, Issue:
1
Journal Article
Peer reviewed
Ruthie Weiss was born with white hair, but her parents did not consider the possibility of there being more to the story until they noticed that she was not visually tracking when she was just a ...month old. Thus began a long and continuing story of the discovery of Ruthie's albinism, her significant visual impairment, but also her courage and determination to do anything and everything her peers do, if not more. But this story is really about how her parents grew to embrace the impact Ruthie (and importantly Ruthie's disability) had on their lives and the lives of everyone with whom Ruthie interacted. The experience of raising Ruthie ultimately led her parents to think about a world where she might not exist, or at least might not exist with albinism. But it also led them to ponder a future in which children with genetic differences like albinism are gene edited using technologies like CRISPR-Cas9.
LDL particle size and number (LDL-P) are emerging lipid risk factors. Nonsystematic reviews have suggested that diets lower in carbohydrates and higher in fats may result in increased LDL particle ...size when compared with higher-carbohydrate diets.
This study aimed to systematically review available evidence and conduct meta-analyses of studies addressing the association of carbohydrate restriction with LDL particle size and LDL-P.
We searched 6 electronic databases on 4 January, 2021 for randomized trials of any length that reported on dietary carbohydrate restriction (intervention) compared with higher carbohydrate intake (control). We calculated standardized mean differences (SMDs) in LDL particle size and LDL-P between the intervention and control groups of eligible studies, and pooled effect sizes using random-effects models. We performed prespecified subgroup analyses and examined the effect of potential explanatory factors. Internal validity and publication bias were assessed using Cochrane’s risk-of-bias tool and funnel plots, respectively. Studies that could not be meta-analyzed were summarized qualitatively.
This review summarizes findings from 38 randomized trials including a total of 1785 participants. Carbohydrate-restricted dietary interventions were associated with an increase in LDL peak particle size (SMD = 0.50; 95% CI: 0.15, 0.86; P < 0.01) and a reduction in LDL-P (SMD = −0.24; 95% CI: −0.43, −0.06; P = 0.02). The effect of carbohydrate-restricted dietary interventions on LDL peak particle size appeared to be partially explained by differences in weight loss between intervention groups and exploratory analysis revealed a shift from small dense to larger LDL subclasses. No statistically significant association was found between carbohydrate-restricted dietary interventions and mean LDL particle size (SMD = 0.20; 95% CI: −0.29, 0.69; P = 0.37).
The available evidence indicates that dietary interventions restricted in carbohydrates increase LDL peak particle size and decrease the numbers of total and small LDL particles.
This review was registered at www.crd.york.ac.uk/prospero/ as CRD42020188745.
The accurate assessment of total body and regional body circumferences, volumes, and compositions are critical to monitor physical activity and dietary interventions, as well as accurate disease ...classifications including obesity, metabolic syndrome, sarcopenia, and lymphedema. We assessed body composition and anthropometry estimates provided by a commercial 3-dimensional optical (3DO) imaging system compared to criterion measures.
Participants of the Shape Up! Adults study were recruited for similar sized stratifications by sex, age (18–40, 40–60, >60 years), BMI (under, normal, overweight, obese), and across five ethnicities (non-Hispanic NH Black, NH White, Hispanic, Asian, Native Hawaiian/Pacific Islander). All participants received manual anthropometry assessments, duplicate whole-body 3DO (Styku S100), and dual-energy X-ray absorptiometry (DXA) scans. 3DO estimates provided by the manufacturer for anthropometry and body composition were compared to the criterion measures using concordance correlation coefficient (CCC) and Bland–Altman analysis. Test-retest precision was assessed by root mean square error (RMSE) and coefficient of variation.
A total of 188 (102 female) participants were included. The overall fat free mass (FFM) as measured by DXA (54.1 ± 15.2 kg) and 3DO (55.3 ± 15.0 kg) showed a small mean difference of 1.2 ± 3.4 kg (95% limits of agreement −7.0 to +5.6) and the CCC was 0.97 (95% CI: 0.96–0.98). The CCC for FM was 0.95 (95% CI: 0.94–0.97) and the mean difference of 1.3 ± 3.4 kg (95% CI: −5.5 to +8.1) reflected the difference in FFM measures. 3DO anthropometry and body composition measurements showed high test-retest precision for whole body volume (1.1 L), fat mass (0.41 kg), percent fat (0.60%), arm and leg volumes, (0.11 and 0.21 L, respectively), and waist and hip circumferences (all <0.60 cm). No group differences were observed when stratified by body mass index, sex, or race/ethnicity.
The anthropometric and body composition estimates provided by the 3DO scanner are precise and accurate to criterion methods if offsets are considered. This method offers a rapid, broadly available, and automated method of body composition assessment regardless of body size. Further studies are recommended to examine the relationship between measurements obtained by 3DO scans and metabolic health in healthy and clinical populations.
Oxysterols are oxidized derivatives of cholesterol that play regulatory roles in lipid biosynthesis and homeostasis. How oxysterol signaling coordinates different lipid classes such as sterols and ...triglycerides remains incompletely understood. Here, we show that 4β-hydroxycholesterol (HC) (4β-HC), a liver and serum abundant oxysterol of poorly defined functions, is a potent and selective inducer of the master lipogenic transcription factor, SREBP1c, but not the related steroidogenic transcription factor SREBP2. By correlating tracing of lipid synthesis with lipogenic gene expression profiling, we found that 4β-HC acts as a putative agonist for the liver X receptor (LXR), a sterol sensor and transcriptional regulator previously linked to SREBP1c activation. Unique among the oxysterol agonists of the LXR, 4β-HC induced expression of the lipogenic program downstream of SREBP1c and triggered de novo lipogenesis both in primary hepatocytes and in the mouse liver. In addition, 4β-HC acted in parallel to insulin-PI3K–dependent signaling to stimulate triglyceride synthesis and lipid-droplet accumulation. Thus, 4β-HC is an endogenous regulator of de novo lipogenesis through the LXR-SREBP1c axis.
Objective
The aim of this study was to determine whether a Mediterranean‐style, ketogenic diet mobile health application (app) with breath acetone biofeedback is superior to a calorie‐restricted, ...low‐fat diet app in promoting weight loss.
Methods
Participants (n = 155) with overweight/obesity (mean SD: age 41 11 years, BMI = 34 5 kg/m2, 71% female) were randomized to one of the interventions delivered entirely via app. Participants received a wireless scale and were instructed to take daily weight measurements. A third‐party laboratory collected blood samples at baseline and 12 weeks.
Results
Weight loss at 12 weeks was greater in the ketogenic (−5.6 kg; 95% CI: −6.7 kg to −4.5 kg) compared with the low‐fat group (−2.5 kg; 95% CI: −3.6 kg to −1.4 kg) (between‐group difference: −3.1 kg; 95% CI: −4.6 kg to −1.5 kg; p < 0.001). Weight loss at 24 weeks indicated durability of the effect (between‐group difference: −5.5 kg; 95% CI: −8.3 kg to −2.8 kg; p < 0.001). Secondary/exploratory outcomes of hemoglobin A1c and liver enzymes were improved to a greater extent in the ketogenic diet group (p < 0.01).
Conclusions
Among adults with overweight/obesity, a ketogenic diet app with breath acetone biofeedback was superior to a calorie‐restricted diet app at promoting weight loss in a real‐world setting.
Identification of the mechanisms by which the coagulation protease thrombin
activates platelets is critical for understanding haemostasis and thrombosis.
Thrombin activates cells at least in part by ...cleaving protease-activated G-protein-coupled
receptors (PARs). PAR3 and PAR4 are thrombin receptors expressed
in mouse platelets. Inhibition of thrombin binding to mPAR3
(ref. 4) and knockout of the mPAR3 gene
inhibited mouse platelet activation at low but not high concentrations of
thrombin. Thus PAR3 is important for thrombin signalling in mouse platelets.
Expression of human PAR3 in heterologous expression systems reliably resulted
in responsiveness to thrombin. Curiously, despite its importance
for the activation of mouse platelets by thrombin, mouse
PAR3 (mPAR3) did not lead to thrombin signalling even when overexpressed.
We now report that mPAR3 and mPAR4 interact in a novel way: mPAR3 does not
itself mediate transmembrane signalling but instead functions as a cofactor
for the cleavage and activation of mPAR4 by thrombin. This establishes a paradigm
for cofactor-assisted PAR activation and for a G-protein-coupled receptor's
acting as an accessory molecule to present ligand to another receptor.
The prevalence of gout has increased in recent decades. Several clinical studies have demonstrated an association between gout and coronary heart disease, but direct cardiovascular imaging of ...monosodium urate (MSU) deposits by using dual-energy computed tomography (DECT) has not been reported to date.
To compare coronary calcium score and cardiovascular MSU deposits detected by DECT in patients with gout and controls.
This prospective Health Insurance Portability and Accountability Act-compliant study included patients with gout and controls who presented to a rheumatologic clinic from January 1, 2017, to November 1, 2018. All consecutive patients underwent DECT to assess coronary calcium score and MSU deposits in aorta and coronary arteries. In addition, cadavers were assessed by DECT for cardiovascular MSU deposits and verified by polarizing microscope. Analysis began in January 2017.
Detection rate of cardiovascular MSU deposits using DECT in patients with gout and control group patients without a previous history of gout or inflammatory rheumatic diseases.
A total of 59 patients with gout (mean SD age, 59 5.7 years; range, 47-89 years), 47 controls (mean SD age, 70 10.4 years; range, 44-86 years), and 6 cadavers (mean SD age at death, 76 17 years; range, 56-95 years) were analyzed. The frequency of cardiovascular MSU deposits was higher among patients with gout (51 86.4%) compared with controls (7 14.9%) (χ2 = 17.68, P < .001), as well as coronary MSU deposits among patients with gout (19 32.2%) vs controls (2 4.3%) (χ2 = 8.97, P = .003). Coronary calcium score was significantly higher among patients with gout (900 Agatston units AU; 95% CI, 589-1211) compared with controls (263 AU; 95% CI, 76-451; P = .001) and also significantly higher among 58 individuals with cardiovascular MSU deposits (950 AU; 95% CI, 639-1261) compared with 48 individuals without MSU deposits (217 AU; 95% CI, 37-397; P < .001). Among 6 cadavers, 3 showed cardiovascular MSU deposits, which were verified by polarizing light microscope.
Dual-energy computed tomography demonstrates cardiovascular MSU deposits, as confirmed by polarized light microscopy. Cardiovascular MSU deposits were detected by DECT significantly more often in patients with gout compared with controls and were associated with higher coronary calcium score. This new modality may be of importance in gout population being at risk from cardiovascular disease.
Objective
This study examined whether body shape and composition obtained by three‐dimensional optical (3DO) scanning improved the prediction of metabolic syndrome (MetS) prevalence compared with BMI ...and demographics.
Methods
A diverse ambulatory adult population underwent whole‐body 3DO scanning, blood tests, manual anthropometrics, and blood pressure assessment in the Shape Up! Adults study. MetS prevalence was evaluated based on 2005 National Cholesterol Education Program criteria, and prediction of MetS involved logistic regression to assess (1) BMI, (2) demographics‐adjusted BMI, (3) 85 3DO anthropometry and body composition measures, and (4) BMI + 3DO + demographics models. Receiver operating characteristic area under the curve (AUC) values were generated for each predictive model.
Results
A total of 501 participants (280 female) were recruited, with 87 meeting the criteria for MetS. Compared with the BMI model (AUC = 0.819), inclusion of age, sex, and race increased the AUC to 0.861, and inclusion of 3DO measures further increased the AUC to 0.917. The overall integrated discrimination improvement between the 3DO + demographics and the BMI model was 0.290 (p < 0.0001) with a net reclassification improvement of 0.214 (p < 0.0001).
Conclusions
Body shape measures from an accessible 3DO scan, adjusted for demographics, predicted MetS better than demographics and/or BMI alone. Risk classification in this population increased by 29% when using 3DO scanning.
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