Effects of Restricted-time and Psychochrononutritional Feeding in People With Metabolic Syndrome (PSICRONUT)

Effect of a Restricted Time and Psychochrononutritional Feeding Intervention Program on the Nutritional Status of People With Metabolic Syndrome in Ciudad Guzmán

Metabolic syndrome is a cluster of risk factors, including abdominal obesity, high blood pressure, high triglycerides, and insulin resistance, that increase the risk of developing type 2 diabetes and cardiovascular disease. The prevalence of this syndrome is rising in Mexico. Recent research suggests that when we eat is as important as what we eat. Therefore, chrononutritional strategies such as time-restricted eating (TRE), where food intake is confined to a specific daily time window, have been developed and shown promising benefits. However, there are documented barriers to maintaining this nutritional strategy over time. Therefore, this study proposes that combining TRE with a psychochrononutritional program (integrating psychological, chronobiological, and nutritional components) will improve adherence to the nutritional strategy and lead to better health outcomes than only prescribing a specific eating window.

To this end, 64 adults (18-60 years old) with metabolic syndrome will be recruited in Ciudad Guzmán, Jalisco, Mexico. The TRE intervention will last eight weeks and include two groups. One group will undergo a psychochrononutritional intervention, whereas the other will receive only instructions regarding the eating window. Within each group, two subgroups will be formed: one assigned to an 8-hour eating window, and the other to a 10-hour window. Before and after the intervention, anthropometric, biochemical (lipid profile and plasma glucose), clinical (blood pressure), and dietary assessments will be performed. We expect reductions in blood pressure, glucose, triglycerides, and waist circumference as well as better adherence in the psychochrononutritional intervention group.

Study Overview

• Status: Recruiting
• Conditions: Metabolic Syndrome
• Intervention / Treatment: Behavioral: Time restricted eating; Behavioral: Psychochrononutritional intervention

Detailed Description

Metabolic syndrome is a condition characterized by risk factors such as abdominal obesity, insulin resistance, hypertension, high triglycerides, and low HDL cholesterol. Together, these factors increase the likelihood of developing type 2 diabetes and cardiovascular disease. Given the growing prevalence of metabolic syndrome in Mexico and in the state of Jalisco, it is essential to develop strategies that contribute to its prevention and treatment.

Whitin this context, chrononutrition has gained prominence as evidence continues to show the benefits of aligning food intake with circadian rhythms. Time-restricted eating (TRE) has been proposed as an effective strategy for preserving and maintaining the body's physiological health. Emerging evidence suggests it is an effective approach for individuals with metabolic syndrome, as it can improve glucose metabolism, reduce abdominal obesity, and lower the risk of developing metabolic syndrome.

The implementation of a TRE plan can be more effective when combined with a psychonutritional intervention, as this can improve adherence to the nutritional treatment and lead to better long-term results.

Therefore, this study aims to determine the effect of a TRE and a psychochrononutritional intervention program on the nutritional status of individuals with metabolic syndrome in Ciudad Guzmán, Jalisco. A randomized controlled trial will be conducted in adult residents, aged 18 to 60 years, of both sexes, diagnosed with metabolic syndrome. The sample size was calculated using a two-mean comparison equation, considering a 10% attrition rate. Resulting in a total sample of 64 participants, 32 for each group.

The study will be carried out in three phases. Phase one will include participants recruitment and confirmation of metabolic syndrome diagnosis. The second phase will integrate a baseline assessment, including anthropometric (weight, percentage of fat and muscle mass, waist circumference) and nutritional measurements, and questionnaires (diet quality index, the Chrononutrition Profile Questionnaire, adherence to treatment and the Pittsburgh Sleep Quality Index). The same variables will be evaluated at the end of the study. Participants will then complete an eight-week restricted-time eating intervention and will be assigned into two groups: one will receive psychonutritional support, and the other will only be given instructions regarding the eating window. Within each group, two subgroups will be created: one will have an 8-hour window, and the other a 10-hour eating window. The third phase will involve a follow up, measuring the same variables taken in phase one.

The data will be analyzed using the statistical software R. Descriptive analyses (means, standard deviations, frequencies, and percentages) will be calculated, followed by a normality test. A paired-samples t-test will be conducted to compare changes before and after the intervention in the following variables: a) anthropometric parameters: body weight, fat and muscle mass, and waist circumference; b) biochemical parameters: fasting plasma glucose, total cholesterol and fractions, and blood pressure; c) nutritional and behavioral variables: eating window and adherence to the eating schedule. In addition, an ANOVA or independent samples t-test will be performed to evaluate the differences between the groups: the group with psychochrononutritional intervention versus the group with minimal intervention, as well as the group with an 8-hour restricted eating window versus a 10-hour restricted eating window.

Expected outcomes include reductions in triglycerides, LDL cholesterol, fasting plasma glucose, blood pressure, and waist circumference, as well as an increase in HDL cholesterol. It is hypothesized that these improvements will be greater in the experimental groups, along with a higher adherence to the intervention. Collectively, these findings will help determine the effect of a TRE intervention combined with a psychochrononutritional approach and assess whether this strategy is a feasible option for improving metabolic health in patients with this condition.

• Study Type: Interventional
• Enrollment (Estimated): 64
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Ana P Zepeda Salvador, PhD; Phone Number: 341 575 2222; Email: ana.zepeda@cusur.udg.mx

Study Locations

• Mexico
  • Jalisco
    • Ciudad Guzmán, Jalisco, Mexico, 49000
      • Recruiting
      • Centro Universitario del Sur

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age 18 to 60 years
• Both sexes
• Feeding window ≥14 h/day
• Usual sleep duration >6.5 h

• Individuals diagnosed with metabolic syndrome who meet three or more of the criteria from Panel III of the National Cholesterol Education Program's Adult Treatment Guidelines:

  • Waist circumference: ≥102 cm for men, ≥88 cm for women
  • Triglycerides: ≥150 mg/dL or on treatment for hypertriglyceridemia
  • High-Density Lipoprotein (HDL) cholesterol: <40 mg/dL for men, <50 mg/dL for women
  • Blood pressure: systolic ≥130 mmHg and diastolic ≥85 mmHg or on treatment for hypertension
  • Fasting plasma glucose: ≥100 mg/dL
• Individuals who provide informed consent

Exclusion Criteria:

• (based on participant self-report unless medical records are available)

  • Pregnancy or lactation
  • Currently enrolled in a weight loss program
  • Current treatment with antidepressants, medications that affect glucose metabolism or appetite, or immunosuppressant therapy
  • History or presence of eating disorders
  • Sleep apnea

Elimination Criteria:

• Participants who do not attend more than two sessions of the psychochrononutritional intervention program.
• Participants who decide to withdraw their consent to continue in the study at any time for any reason.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: Minimal intervention group; Participants will be instructed to adhere to a specific eating window, with flexibility to select their daily eating-window start and end times, as long as they fall within an 8- or 10-hour period. This intervention will last 8 weeks, during which they are instructed to consume all their caloric intake within the established time window.	Behavioral: Time restricted eating; Behavioral and dietary intervention in which participants are instructed to consume all their food and caloric beverages within a fixed window (8 or 10 hours, depending on arm assignment). Outside of this window, only water or non-caloric beverages are permitted. The intervention will last 8 weeks.; Other Names: Time restricted feeding
Experimental: Grupo experimental; Participants will be instructed to adhere to an 8- or 10-hour eating window, with flexibility to select their daily eating-window start and end times but must concentrate their caloric intake within that period. Additionally, the group receives a psychochrononutritional intervention consisting of weekly group sessions with an educational and behavioral focus for 8 weeks.	Behavioral: Time restricted eating; Behavioral and dietary intervention in which participants are instructed to consume all their food and caloric beverages within a fixed window (8 or 10 hours, depending on arm assignment). Outside of this window, only water or non-caloric beverages are permitted. The intervention will last 8 weeks.; Other Names: Time restricted feeding; Behavioral: Psychochrononutritional intervention; Participants will receive a structured psychochrononutritional intervention consisting of eight weekly sessions. The program will cover the following topics: Chrononutrition: The internal clock of eating.; Food groups and healthy menu planning.; Portion control: Learning to measure appropriately.; Effects of sugary drinks.; Sleep and its impact on eating habits.; Social and cultural factors in eating habits.; The relationship between physical activity and nutrition.; Making informed nutritional decisions.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Waist circumference	Waist circumference: A decrease in waist circumference is expected, ≤102 cm in men and ≤88 cm in women. Measured in centimeters using a measuring tape at the level of the navel, at the end of a normal exhalation.	At the beginning (week 1) and end of the intervention (week 8).
Changes in Blood Pressure	Blood Pressure: A decrease in blood pressure of ≤130/85 mmHg is expected. Measurement of systolic and diastolic blood pressure using a digital blood pressure monitor.	At the beginning (week 1) and end of the intervention (week 8).
Changes in Glucose	Glucose: A decrease in glucose level to <110 mg/dL is expected. Measurement of fasting plasma glucose, measured through a venous blood sample obtained between 7:30 and 8:30 am and processed using an automated colorimetric method.	At the beginning (week 1) and end of the intervention (week 8).
Changes in HDL cholesterol	HDL cholesterol: An increase in its values is expected, with a normal range of >40 mg/dL in men and >50 mg/dL in woman. The increase will mean better cardiovascular outcomes. Measurement of HDL cholesterol measured through a venous blood sample obtained between 7:30 and 8:30 am and processed using an automated colorimetric method.	At the beginning (week 1) and end of the intervention (week 8).
Changes in triglycerides levels	Triglycerides: a decrease in values is expected, with a reference range <150 mg/dL. The decrease will mean better cardiovascular outcomes. Measurement of serum triglycerides measured through a venous blood sample obtained between 7:30 and 8:30 am and processed using an automated colorimetric method.	At the beginning (week 1) and end of the intervention (week 8).
Treatment Adherence	Degree to which participants follow the recommendations of the intervention program, it will be measured by self-reporting. Adherence is expected four out of seven days a week.	Monitoring for 8 weeks.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes in Body weight	Body weight: An average reduction of 10% in initial body weight is expected at the end of the intervention. Measurement in kilograms using a digital scale. The participant should be barefoot, wearing as little clothing as possible, and preferably fasting.	At the beginning (week 1) and end of the intervention (week 8).
Body composition analysis	It will be evaluated by electrical bioimpedance (InBody®), comparing the baseline measurement with the final measurement at week 8. A healthy body fat percentage will be taken as a reference point: ≤25% in women and ≤15% in men. Por otro lado, a healthy body muscle considering an increase in relation to healthy reference values: ≥35% in men and ≥25% in women.	At the beginning (week 1) and end of the intervention (week 8).
Changes in visceral fat	Changes in visceral fat measurement performed by electrical bioimpedance (InBody®).	At the beginning (week 1) and end of the intervention (week 8).
Mexican Diet Quality Index	The Mexican Diet Quality Index (IACDMx) will be applied, which classifies foods and beverages into 13 groups. One point is assigned to each component if its energy percentage meets the recommendation. The food classification and cut-off points are based on the energy percentage, considering the energy intake recommendation for each group, in relation to the total daily energy intake of 2,500 kcal proposed by the commission. The score is grouped into five categories: ≤5, 6, 7, 8, and ≥9 points.	At the beginning (week 1) and end of the intervention (week 8).
Sleep quality	Sleep quality will be assessed subjectively using the Pittsburgh Sleep Quality Index (PSQI). This instrument allows for the analysis of qualitative dimensions, such as sleep depth and daytime functioning, as well as quantitative variables (sleep latency, duration, and frequency of awakenings), using a rating scale that ranges from very good to good, poor, and very poor.	At the beginning (week 1) and end of the intervention (week 8).

Collaborators and Investigators

• Sponsor: University of Guadalajara
• Investigators: Study Chair: Yadira V Martínez Vázquez, PhD students, University of Guadalajara; Study Chair: Alma G Martínez Moreno, PhD, University of Guadalajara; Study Chair: César A Gómez Acosta, PhD, Universidad de Pamplona; Study Chair: Ana C Espinoza Gallardo, PhD, University of Guadalajara

Publications and helpful links

General Publications

• Kozlov MM, Chernomordik LV. The protein coat in membrane fusion: lessons from fission. Traffic. 2002 Apr;3(4):256-67. doi: 10.1034/j.1600-0854.2002.030403.x.

Study record dates

Study Major Dates

• Study Start (Actual): December 4, 2025
• Primary Completion (Estimated): April 1, 2026
• Study Completion (Estimated): June 1, 2026

Study Registration Dates

• First Submitted: January 28, 2026
• First Submitted That Met QC Criteria: January 28, 2026
• First Posted (Actual): February 5, 2026

Study Record Updates

• Last Update Posted (Actual): February 18, 2026
• Last Update Submitted That Met QC Criteria: February 15, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Keywords: Metabolic syndrome; Eating Behavior; Time restricted eating; Chrononutrition; Psychochrononutrition
• Additional Relevant MeSH Terms: Metabolic Diseases; Glucose Metabolism Disorders; Insulin Resistance; Hyperinsulinism; Behavior; Nutritional and Metabolic Diseases; Behavior, Animal; Fasting; Metabolic Syndrome; Feeding Behavior; Intermittent Fasting
• Other Study ID Numbers: CIP/T/36/25; DCAN/006/2025 (Other Identifier: Approval number of the Academic Board of the Doctorate in Behavioral Science with a focus on Food and Nutrition, Univer)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: For security and data protection reasons, access to participants' identities is restricted. Sharing identification forms with external researchers contradicts the principle of purpose limitation of consent, which stipulates that personal information will be treated anonymously and privately, ensuring that no data that could re-identify subjects is disclosed outside the authorized research team.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No