Effects of Zinc Supplementation on Patients With Elevated Glycemic Status

Effects of Zinc Supplementation on Patients With Elevated Glycemic Status: A Randomized Double-blind Placebo-controlled Clinical Trial

The goal of this randomized, double-blind, placebo-controlled study included patients with elevated glycemic status is to investigate whether zinc supplementation (4mg per day) has beneficial effects on controlling blood glucose.

Study Overview

• Status: Not yet recruiting
• Conditions: Elevated Blood Glucose
• Intervention / Treatment: Dietary supplement: Zinc-enriched yeast capsule; Dietary supplement: Edible yeast placebo capsule

Detailed Description

The goal of this randomized, double-blind, placebo-controlled study included patients with elevated glycemic status is to investigate whether zinc supplementation (4mg per day) has beneficial effects on controlling blood glucose.

About 124 patients aged 18 years or older, had resided locally for at least one year, with elevated glycemic status will be enrolled in the study. Patients with elevated glycemic status are defined as meeting any of the following criteria:

1. Fasting blood glucose ≥ 6.1 mmol/L;
2. Glycated hemoglobin (HbA1c) ≥ 5.7%;
3. Oral glucose tolerance test (OGTT) 2-hour or postprandial blood glucose ≥ 7.8 mmol/L;
4. Patients with previously diagnosed type 2 diabetes with stable drug hypoglycemic treatment and blood glucose controlled well.

Eligible participants will be assigned by chance to one of two groups: (1) daily zinc supplementation: zinc-enriched yeast capsules (4 mg); (2) daily edible yeast placebo capsules (not zinc-enriched) (4mg). Randomization will be conducted.

At enrollment, baseline questionnaires are designed to collect data on sociodemographic factors, lifestyle habits, health status, and medical conditions. Participants in both groups will take one capsule that contained either Zinc-enriched yeast or edible yeast placebo each day until the end of the intervention period.

Participants will be followed up two times (3 months and 6 months post-intervention), and receive a single stage-specific dosage at any given follow-up time. During each follow-up visit, participants will complete a questionnaire survey, a 3-day 24-hour dietary recall, and undergo physical measurements. Blood, urine, and stool samples will also be obtained in the study center, fasting blood glucose, HbA1c and other biochemical indicators will also be detected at the same time.

The primary outcomes, including fasting blood glucose and HbA1c will be measured using blood samples. Secondary outcomes in this study include changes in blood lipids (such as total cholesterol, triglycerides, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol), trends in plasma zinc levels, inflammatory factors, oxidative stress indexes, other blood indicators and liver and kidney function indicators. Data will be collected and analyzed.

• Study Type: Interventional
• Enrollment (Estimated): 124
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Zhilei Shan, PHD; Phone Number: 15871720906; Email: zhileishan@hust.edu.cn
• Study Contact Backup: Name: Hongkun Di, BM; Phone Number: 15931891138; Email: hongkundi2020@163.com

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

1. Fasting blood glucose ≥ 6.1 mmol /L;
2. HBA1c ≥ 5.7%;
3. OGTT 2-hour or postprandial blood glucose ≥ 7.8 mmol/L;
4. Patients with previously diagnosed type 2 diabetes with stable drug hypoglycemic treatment and blood glucose controlled well.

Exclusion Criteria:

1. Age < 18 years, or currently pregnant;
2. Individuals with severe obesity, thyroid disease, cardiovascular or cerebrovascular diseases, or other serious health conditions;
3. Individuals with a previous diagnosis of type 2 diabetes currently receiving insulin therapy;
4. Individuals who have taken zinc-related supplements within three months prior to baseline inclusion;
5. Individuals using other nutritional supplements or with poor lifestyle habits;
6. Individuals with unstable body weight in the past three months (fluctuations > 5 kg);
7. Individuals with a history of major surgery within the past three months or planned major surgery within the next month;
8. Individuals allergic to the intervention materials;
9. Individuals who did not adhere to the prescribed consumption of the study product, affecting efficacy or safety assessment;
10. Individuals with positive urinary protein or serum creatinine greater than 1.2 times the upper limit of normal (men: serum creatinine > 133.2 μmol/L, women: serum creatinine > 97.2 μmol/L) at screening;
11. Individuals with elevated alanine aminotransferase (ALT) levels at screening (men: ALT > 50 U/L, women: ALT > 35 U/L).

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Zinc supplementation; zinc-enriched yeast capsule, 15mg/d	Dietary supplement: Zinc-enriched yeast capsule; Daily zinc supplementation: zinc-enriched yeast capsules (15 mg) for a total of 6 months.
Placebo Comparator: Edible yeast placebo; Edible yeast placebo capsule, 15mg/d	Dietary supplement: Edible yeast placebo capsule; Daily edible yeast placebo capsules (not zinc-enriched) (15 mg) for a total of 6 months.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Glycated hemoglobin (HbA1c)	Concentration of HbA1c, measured in the percentage of hemoglobin	0 week, 12th week, and 24th week in the intervention period
Concentration of fasting blood glucose (FBG)	Concentration of FBG, measured in mmol/L	0 week, 12th week, and 24th week in the intervention period

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Concentration of plasma zinc	Concentration of plasma zinc concentrations, measured in mg/dL	0 week, 12th week, and 24th week in the intervention period
Concentration of fasting plasma insulin (FPI)	Concentration of FPI, measured in μIU/mL	0 week, 12th week, and 24th week in the intervention period
Concentration of plasma c-peptide	Concentration of plasma c-peptide, measured in nmol/L	0 week, 12th week, and 24th week in the intervention period
Homeostatic model assessment of insulin resistance (HOMA-IR)	HOMA-IR can be calculated as (FPI [μU/mL] × FBG [mmol/L]) / 22.5	0 week, 12th week, and 24th week in the intervention period
Homeostatic model assessment of β-cell function (HOMA-β)	HOMA-β is calculated as (20 × FPI [μU/mL]) / (FBG [mmol/L] - 0.195)	0 week, 12th week, and 24th week in the intervention period
Homeostatic model assessment of insulin sensitivity (HOMA-S)	HOMA-S is calculated as 1 / HOMA-IR	0 week, 12th week, and 24th week in the intervention period
Concentration of blood lipids	Concentration of blood lipids: total cholesterol, triglycerides, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, measured in mmol/L	0 week, 12th week, and 24th week in the intervention period
Concentration of C-reactive protein (CRP)	Concentration of CRP, measured in mg/dL	0 week, 12th week, and 24th week in the intervention period
Concentration of interleukin-6 (IL-6)	Concentration of IL-6, measured in pg/mL	0 week, 12th week, and 24th week in the intervention period
Concentration of malondialdehyde (MDA)	Concentration of MDA, measured in μmol/L	0 week, 12th week, and 24th week in the intervention period
Activity of Cu-Zn superoxide dismutase (SOD)	Activity of Cu-Zn SOD, measured in U/mL	0 week, 12th week, and 24th week in the intervention period
Concentration of homocysteine (HCY)	Homocysteine (HCY) [μmol/L]	0 week, 12th week, and 24th week in the intervention period
Concentration of plasma albumin (ALB)	Concentration of ALB, measured in g/dL	0 week, 12th week, and 24th week in the intervention period
Concentration of plasma creatinine	Concentration of plasma creatinine, measured in μmol/L	0 week, 12th week, and 24th week in the intervention period

Collaborators and Investigators

• Sponsor: Zhilei Shan

Study record dates

Study Major Dates

• Study Start (Estimated): July 1, 2025
• Primary Completion (Estimated): December 1, 2025
• Study Completion (Estimated): December 1, 2025

Study Registration Dates

• First Submitted: January 29, 2025
• First Submitted That Met QC Criteria: January 29, 2025
• First Posted (Actual): February 4, 2025

Study Record Updates

• Last Update Posted (Actual): May 14, 2025
• Last Update Submitted That Met QC Criteria: May 9, 2025
• Last Verified: March 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Metabolic Diseases; Glucose Metabolism Disorders; Hyperglycemia
• Other Study ID Numbers: S235

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No