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.
