Emily N C Manoogian

• PhD, UMass Amherst; Bachelor of Arts, UC Berkeley
• PostDoc Position at Salk Institute for Biological Studies

Objective Metabolic improvements may precede weight loss. We compared the effects of self‐selected 8‐h time‐restricted eating (TRE), 15% caloric restriction (CR), and unrestricted eating (UE) on weight, body composition, caloric intake, glycemic measures, and metabolic flexibility. Methods In this 12‐week randomized‐controlled trial, we measured w...

Objective Post‐prandial glucose response (PPGR) is a risk factor for cardiovascular disease. Meal carbohydrate content is an important predictor of PPGR, but dietary interventions to mitigate PPGR are not always successful. A personalized approach, considering behaviour and habitual pattern of glucose excursions assessed by continuous glucose monit...

Background: Time-restricted eating (TRE) may extend the cardiometabolic health benefits of calorie restriction (CR). However, few studies have compared its effect on the circadian regulation of metabolic processes, including glucose metabolism. The optimal time of day to initiate TRE also remains unclear. Aim and hypothesis: To compare CR alone or...

Purpose: Time-restricted eating (TRE) helps regulate rest-activity rhythms, blood glucose, and other diurnally regulated energetics processes, which may have implications for persistent fatigue. In a randomized controlled trial, we tested the effects of TRE vs. control on fatigue in cancer survivorship. Methods: Adult cancer survivors were recruite...

Introduction/Hypothesis: Time-restricted eating (TRE) is a lifestyle intervention in which there is an extended fasting period overnight of about 14 hours with a 10-hour eating window. Clinical and animal studies have shown that TRE decreases inflammation, and improves immune autonomic and mitochondrial function and cardiometabolic parameters. Pati...

This study investigates the impact of habitual late calorie intake on glucose metabolism in adults with overweight or obesity and diet or metformin-controlled prediabetes or type 2 diabetes independently of body weight, fat mass, energy intake or diet composition. Participants (n = 26) were classified as Later Eaters (LE) if ≥45% daily calories wer...

Background The primary objective of this trial is to examine the mechanisms of time-restricted eating (TRE) as an adjunct to psychiatric care for people with bipolar disorder (BD) with sleep or circadian disruptions. This study builds on prior studies of circadian disruption in BD as well as growing evidence that TRE improves circadian functioning....

Background: Time-restricted eating (TRE), limiting daily dietary intake to a consistent 8 to 10 hours without mandating calorie reduction, may provide cardiometabolic benefits. Objective: To determine the effects of TRE as a lifestyle intervention combined with current standard-of-care treatments on cardiometabolic health in adults with metaboli...

Although fasting is increasingly applied for disease prevention and treatment, consensus on terminology is lacking. Using Delphi methodology, an international, multidisciplinary panel of researchers and clinicians standardized definitions of various fasting approaches in humans. Five online surveys and a live online conference were conducted with 3...

Metabolic syndrome (MetS) and a prolonged daily eating window (EW) are associated with circadian rhythm disruption and increased cardiometabolic risk. Misalignment between circadian timing system and daily rhythms of food intake adversely impacts metabolic regulatory mechanisms and cardiovascular function. Restricting the daily EW by imposing an ea...

Background The primary objective of this randomized controlled trial (RCT) is to establish the effectiveness of time-restricted eating (TRE) compared with the Mediterranean diet for people with bipolar disorder (BD) who have symptoms of sleep disorders or circadian rhythm sleep–wake disruption. This work builds on the growing evidence that TRE has...

This observational pilot study examined the association between diet, meal pattern and glucose over a 2-week period under free-living conditions in 26 adults with dysglycemia (D-GLYC) and 14 with normoglycemia (N-GLYC). We hypothesized that a prolonged eating window and late eating occasions (EOs), along with a higher dietary carbohydrate intake, w...

Molecular and physiological determinants of the timing of reproductive events, including the pre-ovulatory LH surge and seasonal fluctuations in fertility, are incompletely understood. We used the Cryptochrome 1-deficient duper mutant to examine the role of this core circadian clock gene in Syrian hamsters. We find that the phase of the LH surge an...

Many fasting interventions of various durations, cadence, and magnitude of caloric restriction have demonstrated health benefits in both animal models and humans. All these interventions are focused on the duration of fasting and caloric restriction. Time-restricted feeding/eating (TRF/TRE) is unique in that it is based on circadian biology. TRF/TR...

Background: The primary objective of this randomized controlled trial (RCT) is to establish the effectiveness of time-restricted eating (TRE) compared with the Mediterranean diet for people with bipolar disorder (BD) who have symptoms of sleep disorders or circadian rhythm sleep-wake disruption. This work builds on the growing evidence that TRE has...

Time-restricted eating (TRE) has shown potential benefits in optimizing the body's circadian rhythms and improving cardiometabolic health. However, as with all dietary interventions, a participant's ability to adhere to the protocol may be largely influenced by a variety of lifestyle factors. In TRE trials that reported participants' rates of adher...

Objective: Decreased insulin sensitivity and impairment of β-cell function predate and predict development of type 2 diabetes mellitus. Time-restricted eating (TRE) might have a benefit for these parameters. The objective of this pilot study was to investigate this possibility. Methods: Secondary analysis of a randomized controlled trial compari...

Background Time restricted eating (TRE), limiting eating to a specific daily window, is a novel dietary intervention, but the mechanisms by which TRE results in weight loss remain unclear. The goal of the current study was to examine changes in eating patterns, sleep, and late-night eating, and associations with health outcomes in a secondary analy...

Nutritional interventions often rely on subjective assessments of energy intake (EI), but these are susceptible to measurement error. PURPOSE: To introduce an accelerometer-based intake-balance method for assessing EI using data from a time-restricted eating (TRE) trial. METHODS: 19 participants with overweight/obesity (25-63 years old; 16 females)...

Objective: This study explored the impact of time-restricted eating (TRE) versus standard dietary advice (SDA) on bone health. Methods: Adults with ≥1 component of metabolic syndrome were randomized to TRE (ad libitum eating within 12 hours) or SDA (food pyramid brochure). Bone turnover markers and bone mineral content/density by dual energy x-r...

Over a quarter of the workforce in industrialized countries does shift work, which increases the risk for cardiometabolic disease. Yet shift workers are often excluded from lifestyle intervention studies to reduce this risk. In a randomized control trial with 137 firefighters who work 24-h shifts (23–59 years old, 9% female), 12 weeks of 10-h time-...

The Cryptochrome 1 ( Cry1 )–deficient duper mutant hamster has a short free-running period in constant darkness (τ DD ) and shows large phase shifts in response to brief light pulses. We tested whether this measure of the lability of the circadian phase is a general characteristic of Cry1 -null animals and whether it indicates resistance to jet lag...

Objective: Time-restricted eating (TRE) restores circadian rhythms in mice, but the evidence to support this in humans is limited. The objective of this study was to investigate the effects of TRE on 24-hour profiles of plasma metabolites, glucoregulatory hormones, and the subcutaneous adipose tissue (SAT) transcriptome in humans. Methods: Men (...

Re-aligning eating patterns with biological rhythm can reduce the burden of metabolic syndrome in older adults with overweight or obesity. Time-restricted eating (TRE) has been shown to result in weight loss and improved cardiometabolic health while being less challenging than counting calories. The New York Time-Restricted EATing study (NY-TREAT)...

Calorie restriction (CR) and time-restricted eating (TRE) are distinctly different dietary management strategies with overlapping health outcomes. After two years of CR, healthy participants in the Comprehensive Assessment of Long-Term Effects of Reducing Intake of Energy (CALERIE) study showed significant weight-loss relative to the ad libitum int...

The quality and quantity of nutrition impact health. However, chrononutrition, the timing, and variation of food intake in relation to the daily sleep-wake cycle are also important contributors to health. This has necessitated an urgent need to measure, analyze, and optimize eating patterns to improve health and manage disease. While written food j...

Aim To examine the effects of eight weeks of TRE on glucose metabolism and the adipose tissue transcriptome during a metabolic ward stay in men with obesity. Methods In a single-arm, pre-post trial, 15 men (aged 62.9 ± 4 years, body mass index 30.5 ± 2.4 kg/m², waist circumference 113 ± 4 cm) with obesity, but no history of diabetes, were enrolled...

We aim to describe temporal eating patterns in a population of adults with overweight or obesity. In this cross-sectional analysis, data were combined from two separate pilot studies during which participants entered the timing of all eating occasions (>0 kcals) for 10–14 days. Data were aggregated to determine total eating occasions, local time of...

Time-restricted feeding (TRF, animal-based studies) and time-restricted eating (TRE, humans) are an emerging behavioral intervention approach based on the understanding of the role of circadian rhythms in physiology and metabolism. In this approach, all calorie intake is restricted within a consistent interval of less than 12 hours without overtly...

Eating architecture is a term that describes meal frequency, meal timing, and meal size and the daily variation in each of these. The aim of this study was to determine the relationship between components of eating architecture on body fat and markers of glycaemic control in healthy adults at increased risk of type 2 diabetes (T2DM). Participants (...

The goal of this study was to test the feasibility of time restricted eating (TRE) in adults with overweight and obesity. Participants (n = 50) logged all eating occasions (>0 kcal) for a 2-week run-in period using a smartphone application. Participants with eating duration ≥14 h enrolled in an open label, non-randomized, prospective 90-day TRE int...

Introduction Career firefighters experience chronic circadian rhythm disruption, increasing their risk of cardiometabolic disease. The recent discovery that eating patterns regulate circadian rhythmicity in metabolic organs has raised the hypothesis that maintaining a consistent daily cycle of eating and fasting can support circadian rhythms and re...

Time-Restricted Eating (TRE) is a consistent 6-12-hour daily eating window without any overt caloric reduction. TRE has been shown in pre-clinical and clinical studies to have widespread benefits including improved cardiometabolic health. Most clinical trials have studied healthy or overweight participants, but the effect of TRE on patients undergo...

Impairment of β-cell function is a precursor to impaired glucose tolerance, which is a pathophysiological basis for the development of Type 2 Diabetes Mellitus (T2DM). Previous literature has reported varying effects of TRE on metabolic measures in different populations, yet the effect of TRE on β-cell function has not been well-characterized. We h...

Time-restricted eating (TRE) reduces weight in humans, but its effects on quality of life have not been well characterized. By performing a secondary analysis of a randomized clinical trial, we examined the effects of TRE (12-week intervention, 8 h eating window) vs. non-TRE (unrestricted eating) on quality of life (QoL) measures. Twenty subjects w...

Weight loss is a major focus of research and public health efforts. Time-restricted eating (TRE) is shown to be effective for weight loss, but the impact on bone is unclear. Short-term TRE studies show no effect on bone mineral density (BMD), but no study has measured bone turnover markers. This secondary analysis examined the effect of 12 weeks of...

Weight loss is key to controlling the increasing prevalence of metabolic syndrome (MS) and its components, i.e., central obesity, hypertension, prediabetes and dyslipidaemia. The goals of our study were two-fold. First, we characterised the relationships between eating duration, unprocessed and processed food consumption and metabolic health. Durin...

The prevalence of metabolic syndrome (MS) is increasing, affecting approximately 1 billion people. Weight loss is key to control MS components, i.e. central obesity, hypertension, prediabetes, and dyslipidemia. Here, we characterised the relationships between eating duration, unprocessed and processed food consumption, and metabolic health. In a 4-...

Metabolic syndrome (MetS) and erratic eating patterns are associated with circadian rhythm disruption which contributes to an increased cardiometabolic risks. Restricting eating period (time-restricted eating, TRE) can restore robust circadian rhythms and improve cardiometabolic health. We describe a protocol of the Time-Restricted Eating on Metabo...

Time-restricted eating (TRE) can facilitate weight loss, yet its effect on eating patterns remains unknown. Twenty adults with BMI ≥ 25 kg/m2 underwent a 12-week randomized trial, examining the effect of an 8-h, time-restricted eating intervention on dietary patterns. Oral intake was documented using a smartphone. Dietary patterns, assessed as freq...

Prolonged eating into late evening hours is associated with overweight (OW)/obesity (OB) and increases metabolic risk. Reducing the daily eating window, or time restricted eating (TRE), results in weight loss (WL) and improved metabolism. Our goal was to assess: 1) The eating patterns of adults with OW or OB and 2) The effect of 10h/d TRE, in perso...

Introduction Time-restricted eating (TRE), limiting food intake to a consistent daily window, is emerging as a novel weight loss intervention but impact of TRE on sleep remains unclear. Prior studies reported mixed results but are limited by subjective sleep measurements and lack of a randomized control group. Thus, we examined changes in actigraph...

Objective In contrast to intentionally restricting energy intake, restricting the eating window may be an option for treating obesity. By comparing time‐restricted eating (TRE) with an unrestricted (non‐TRE) control, it was hypothesized that TRE facilitates weight loss, alters body composition, and improves metabolic measures. Methods Participants...

In animal models, time-restricted feeding (TRF) can prevent and reverse aspects of metabolic diseases. Time-restricted eating (TRE) in human pilot studies reduces the risks of metabolic diseases in otherwise healthy individuals. However, patients with diagnosed metabolic syndrome often undergo pharmacotherapy, and it has never been tested whether T...

TRE, restriction of the eating window, reduces weight in animals and humans. We performed a randomized clinical trial examining the effect of TRE on body composition and glycemic measures in overweight humans without diabetes. We hypothesized that TRE will reduce weight and alter body composition compared with unrestricted feeding (non-TRE). 21 ove...

Molecular clocks are present in almost every cell to anticipate daily recurring and predictable changes, such as rhythmic nutrient availability, and to adapt cellular functions accordingly. At the same time, nutrient-sensing pathways can respond to acute nutrient imbalance and modulate and orient metabolism so cells can adapt optimally to a declini...

Objective This study aimed to assess the effects of 9‐hour time‐restricted feeding (TRF), early (TRFe) or delayed (TRFd), on glucose tolerance in men at risk for type 2 diabetes. Methods Fifteen men (age 55 ± 3 years, BMI 33.9 ± 0.8 kg/m²) wore a continuous glucose monitor for 7 days of baseline assessment and during two 7‐day TRF conditions. Part...

Mammalian circadian rhythms are entrained by photic stimuli that are relayed by retinal projections to the core of the suprachiasmatic nucleus (SCN). Neuronal activation, as evidenced by expression of the immediate early gene c‐fos, leads to transcription of the core clock gene per1. The duper mutation in hamsters shortens circadian period and ampl...

Daily rhythms in behavior, physiology, and metabolism are an integral part of homeostasis. These rhythms emerge from interactions between endogenous circadian clocks and ambient light-dark cycles, sleep-activity cycles, and eating-fasting cycles. Nearly the entire primate genome shows daily rhythms in expression in tissue- and locus-specific manner...

Circadian rhythms optimize physiology and health by temporally coordinating cellular function, tissue function, and behavior. These endogenous rhythms dampen with age and thus compromise temporal coordination. Feeding-fasting patterns are an external cue that profoundly influence the robustness of daily biological rhythms. Erratic eating patterns c...

Life on our planet evolved under predictable light:dark cycles and dependent rhythms of nutrient availability. Accordingly, a vast majority of living organisms, ranging from archaea to humans, have adopted molecular mechanisms to anticipate and respond to daily metabolic rhythms. Central to this timing mechanism in mammals is a cell-autonomous mole...

The duper mutation in Syrian hamsters shortens the free-running period of locomotor activity (τDD) to about 23 h and results in a type 0 phase-response curve (PRC) to 15-min light pulses. To determine whether exaggerated phase shifts are specific to photic cues and/or restricted to subjective night, we subjected hamsters to novel wheel confinements...