Effects of Daily Walnut Intake Among the Subjects With Metabolic Syndrome

Not Applicable

Completed

• Conditions: Metabolic Syndrome
• Interventions: Other: food

• Registration Number: NCT03267901
• Lead Sponsor: ICAN Nutrition Education and Research

Brief Summary

Investigators planed to conduct a randomized, controlled, crossover trial to examine the effects of daily walnuts intake among Korean subjects with metabolic syndrome. Primary objective of this study was to investigate the effects of daily walnut intake on changes of metabolic syndrome indices in Koreans with metabolic syndrome age over 30 years old. This study was consisted of four periods: run-in, first intervention, wash-out, and second intervention phases. As 16 weeks of first intervention period began after the run-in phase, the subjects were randomly assigned into one of two groups: walnut group and control group. Participants in walnut group consumed 45 grams of walnuts on a daily basis and participants in control group were provided iso-caloric white bread for first 16 weeks. After the first intervention and wash-out period (6 weeks), second intervention which is crossover of first intervention was started during the next 16 weeks. Anthropometric measurements and biochemical analyses were done at the beginning and the end of each intervention (0, 16, 22, and 38 weeks of trial). Habitual diet was randomly observed using 3-day diet record once during each phase.

Investigators expected to evaluate 1)effects of walnut ingestion on reverting metabolic syndrome to normal status especially by reducing waist circumference and improving serum levels of triglyceride and high-density lipoprotein, 2)beneficial effects of daily walnut consumption on changes of body composition in the subjects with metabolic syndrome, and 3)regulatory effects of daily walnut intake on inflammatory markers and diabetic markers.

Detailed Description

Not available

Study Timeline

• Study Start: 2015-05-01
• Primary Completion: 2017-07-30
• Study Completion: 2017-07-30
• Status Verified: 2017-08
• Study First Submitted: 2017-08-14
• Study First Submitted QC: 2017-08-28
• Last Update Submitted: 2017-08-28
• Study First Posted: 2017-08-30
• Last Update Posted: 2017-08-30

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 119

Inclusion Criteria

at least three out of five metabolic syndrome components

• waist circumference (WC) >90 cm for men and >80 cm for women
• hypertension (DBP ≥85 and <110 mm Hg)
• hyperglycemia (≥100 mg/dL)
• elevated plasma TG concentrations (≥150 mg/dL)
• decreased plasma HDL-C concentrations (<40 mg/dL for men and <50 mg/dL for women)

Exclusion Criteria

• the presence of morbid obesity (BMI ≥40)
• the use of any medication for the control of blood pressure, glucose, or lipid metabolism
• a medical history of hypocaloric diet consumption within the past year
• gastrointestinal tract disorders
• post-menopausal women
• smokers

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Walnut-Control	food	-
Control-Walnut	food	-

Primary Outcome Measures

Name	Time	Method
changes of blood glucose level	after 16 weeks of daily walnut consumption	Blood glucose levels (mg/dL) were measured using blood glucose monitor and test stripts from the finger tip.
changes of blood triglyceride level	after 16 weeks of daily walnut consumption	Serum triglycerides (mg/dL) levels were measured by an enzymatic-colorimetric method.
changes of blood pressure	after 16 weeks of daily walnut consumption	Blood pressure (mmHg) was measured on the right arm using an up-load blood pressure monitor with participants in a comfortably seated position after at least a 5-minute rest.
changes of waist circumference	after 16 weeks of daily walnut consumption	Waist circumferences (cm) were obtained at the midpoint between the lowest rib and the iliac crest and rounded to the nearest 0.1 cm after inhalation and exhalation.
changes of blood high-density lipoprotein cholesterol levels	after 16 weeks of daily walnut consumption	High density lipoprotein cholesterol (mg/dL) levels were determined by a homogeneous enzymatic-colorimetric method.

Secondary Outcome Measures

Name	Time	Method
changes of serum apolipoprotein B level	after 16 weeks of daily walnut consumption	Serum apolipoprotein B (ml/dL) was measured using a turbidimetric immunoassay.
changes of serum leptin level	after 16 weeks of daily walnut consumption	Blood leptin (ug/mL) levels were measured using ELISA.
changes of low-density lipoprotein cholesterol level	after 16 weeks of daily walnut consumption	Low-density lipoprotein cholesterol levels (ml/dL) were determined by a homogeneous enzymatic-colorimetric method.
changes of total cholesterol level	after 16 weeks of daily walnut consumption	Serum total cholesterol levels (ml/dL) were measured by an enzymatic-colorimetric method.
changes of serum adiponectin level	after 16 weeks of daily walnut consumption	Blood adiponectin (ug/mL) levels were measured using ELISA.
changes of serum insulin level	after 16 weeks of daily walnut consumption	Serum insulin (μU/mL) was measured with a commercially available kit, the ultrasensitive insulin ELISA kit using an Epoch microplate spectrophotometer.

Trial Locations

Locations (1)

ICAN Nutrition Education and Research; 🇰🇷 Seoul, Korea, Republic of