Research Summary

Analyzed using Evidence Intelligence™

Melatonin improves glycemic control in type 2 diabetes patients

Last updated August 16, 2026

Key finding

mean difference: -1.30, confidence interval [CI]: -2.41 to -0.19, P = 0.02

This study investigated the effects of melatonin supplementation on glycemic control in patients with type 2 diabetes and chronic periodontitis, finding significant improvements in various health markers.

Quick read

Study at a glance

The essential study design details in one scan.

EvidenceScore™

Moderate

Study type

RCTs

Follow-up

Short-Term (≤3 mo)

Risk of bias

Some Concerns

Save research, organize studies, and quickly find important evidence again.

Plain-language summary

What this paper says

A plain-language read of the study’s main message and where it applies.

Study focus

Clinical relevance

The findings are clinically significant as they suggest that melatonin supplementation may enhance glycemic control and reduce obesity-related health risks in patients with type 2 diabetes and chronic periodontitis. Improved management of these conditions can lead to better overall health outcomes and quality of life for patients.

Keep in mind

Limited sample size may affect generalizability Short duration of the study may not capture long-term effects Potential confounding factors not fully controlled

Published in

Journal Reference

Publication details and source links for this paper.

Hadi B, Ahmad ZJ, Mehrnoosh Z, Hojat AY, Mohammad HH. Effects of Melatonin Supplementation on Glycemic Control in Patients with Type 2 Diabetes and Chronic Periodontitis. Journal of Research in Medical Sciences : The Official Journal of Isfahan University of Medical Sciences. 2022;27:52. doi:10.4103/jrms.JRMS_927_19

View DOI View on PubMed View on PMC

Main Effects

HbA1c decreased significantly by 1.30% (P = 0.02)

Body weight decreased significantly by 3.90 kg (P < 0.001)

BMI decreased significantly by 1.41 kg/m² (P < 0.001)

Evidence network

How this study fits

Understand where this research contributes within the broader evidence network.

Evidence Context

This study contributes evidence to Melatonin and BMI, Body weight, Diastolic blood pressure, and 5 more.

This study contributes evidence to

Intervention

Melatonin

Outcome

BMI

Evidence topic

Weight Loss

Primary intervention

Melatonin

Primary outcomes

BMI
Body weight
Diastolic blood pressure

Evidence topics

Weight Loss HbA1c Reduction

Primary intervention

Melatonin

Primary outcomes

BMI Body weight Diastolic blood pressure

Evidence relationships

Intervention and outcome relationships this study adds to the evidence network.

Evidence pairs

Relationships

Evidence topics

contributes_evidence

Editorial context

Why this study matters

See why this paper is useful beyond its individual results.

Evidence network role

This section describes how the study fits into the current evidence network. It does not determine whether an intervention works on its own.

Moderate contributionModerate confidenceNetwork score: 64

Why it is useful

Contributes to 8 evidence relationships
Includes primary outcome data
Linked to 2 direct semantic evidence topics

Topic contributions

Evidence topic

Contributes evidence

Evidence topic

Contributes evidence

Add related evidence to your Evidence Tracker

Save studies and evidence pages, organize your personal Evidence Tracker, and keep the research you care about in one place.

Primary evidence

Evidence topic

Weight Loss

matched_outcome

Related evidence

Evidence topic

HbA1c Reduction

Save evidence

Core evidence

Study findings

The primary outcomes reported in this study.

BMI

Melatonin → BMI

Evidence Intelligence™

EvidenceScore™: Moderate; Score 69 · Based on 2 studies
ImpactScore™: 100; Very Positive
ConsistencyScore™: 100; consistent

Based on 2 studies

Add to Evidence Tracker

Body weight

Melatonin → Body weight

Evidence Intelligence™

EvidenceScore™: Moderate; Score 69 · Based on 2 studies
ImpactScore™: 100; Very Positive
ConsistencyScore™: 100; consistent

Based on 2 studies

Add to Evidence Tracker

Diastolic blood pressure

Melatonin → Diastolic blood pressure

Evidence Intelligence™

EvidenceScore™: Emerging; Score 59 · Based on 1 study
ImpactScore™: 100; Very Positive
ConsistencyScore™: unclear; Not enough independent studies

Based on 1 study

Add to Evidence Tracker

HbA1c

Melatonin → HbA1c

Evidence Intelligence™

EvidenceScore™: 77; Strong
ImpactScore™: 67; Slightly Positive
ConsistencyScore™: 67; generally_consistent

Based on 3 studies

Add to Evidence Tracker

HDL cholesterol

Melatonin → HDL cholesterol

Evidence Intelligence™

EvidenceScore™: Emerging; Score 59 · Based on 1 study
ImpactScore™: 25; Negative
ConsistencyScore™: unclear; Not enough independent studies

Based on 1 study

Add to Evidence Tracker

Hip circumference

Melatonin → Hip circumference

Evidence Intelligence™

EvidenceScore™: Moderate; Score 69 · Based on 2 studies
ImpactScore™: 100; Very Positive
ConsistencyScore™: 100; consistent

Based on 2 studies

Add to Evidence Tracker

Systolic blood pressure

Melatonin → Systolic blood pressure

Evidence Intelligence™

EvidenceScore™: Moderate; Score 69 · Based on 2 studies
ImpactScore™: 100; Very Positive
ConsistencyScore™: 100; consistent

Based on 2 studies

Add to Evidence Tracker

Waist circumference

Melatonin → Waist circumference

Evidence Intelligence™

EvidenceScore™: Moderate; Score 69 · Based on 2 studies
ImpactScore™: 100; Very Positive
ConsistencyScore™: 100; consistent

Based on 2 studies

Add to Evidence Tracker

Evidence Library

Build your evidence library

Save research, organize studies, and quickly find important evidence again.

Evidence Suggest

HbA1c levels decreased by 1.30%, indicating improved glycemic control.
Participants lost an average of 3.90 kg, suggesting effective weight management.
HDL-C increased by 5.18 mg/dL, reflecting improved lipid profiles.

Who this applies to

Adults aged 30-65 with type 2 diabetes
Patients diagnosed with chronic periodontitis

Keep in Mind

Results may not apply to younger populations or those without chronic periodontitis.
Further studies are needed to confirm long-term effects of melatonin.
Individual responses to supplementation can vary significantly.

Between the Lines

Limited sample size may affect generalizability
Short duration of the study may not capture long-term effects
Potential confounding factors not fully controlled

Evidence Library

Build your evidence library

Save research, organize studies, and quickly find important evidence again.

Connected Evidence

Explore related studies, evidence collections, and research questions.

Relationships organized using the Dediabetes Evidence Intelligence™ framework.

This study contributes to evidence on Melatonin and HbA1c, Melatonin and Body Mass Index.

Related evidence relationships

Explore in Evidence Explorer

This study contributes to the evidence on the following intervention-outcome relationships.

Supplements

Detailed evidence

Melatonin → HbA1c

Supplements

Evidence Intelligence™

EvidenceScore™: 77; Strong
ImpactScore™: 67; Slightly Positive
ConsistencyScore™: 67; generally_consistent

Based on 3 studies

View evidence

Supplements

Detailed evidence

Melatonin → Body Mass Index

Supplements

Evidence Intelligence™

EvidenceScore™: Moderate; Score 69 · Based on 2 studies
ImpactScore™: 100; Very Positive
ConsistencyScore™: 100; consistent

Based on 2 studies

View evidence

Supplements

Detailed evidence

Melatonin → Body Weight

Supplements

Evidence Intelligence™

EvidenceScore™: Moderate; Score 69 · Based on 2 studies
ImpactScore™: 100; Very Positive
ConsistencyScore™: 100; consistent

Based on 2 studies

View evidence

Included in these evidence collections

Curated evidence collections and hubs this study is part of.

HbA1c Evidence Hub

All studies measuring HbA1c

3 studies

outcome_hub

Measures HbA1c as a key outcome.

Melatonin Evidence Hub

All studies on Melatonin

3 studies

intervention_hub

Contributes to Melatonin evidence base.

Body Mass Index Evidence Hub

All studies measuring Body Mass Index

2 studies

outcome_hub

Measures Body Mass Index as a key outcome.

Body Weight Evidence Hub

All studies measuring Body Weight

2 studies

outcome_hub

Measures Body Weight as a key outcome.

Explore more in Evidence Explorer

Jump to pre-filtered views in Evidence Explorer.

All studies on Melatonin and HbA1c

Intervention: MelatoninOutcome: HbA1c

3 results

All studies on Melatonin and BMI

Intervention: MelatoninOutcome: BMI

2 results

All studies on Melatonin

Intervention: Melatonin

3 results

All studies measuring HbA1c

Outcome: HbA1c

3 results

All studies measuring BMI

Outcome: BMI

2 results

Questions answered by this study

Generated from the study's connected evidence using Evidence Intelligence™.

Does Melatonin improve HbA1c?

Strong Evidence

Melatonin may improve HbA1c.

ConsistencyScore™: Results are generally consistent across studies.

Ranked evidence signals

1
HbA1c
EvidenceScore™ Strong | EvidenceScore™ 77.4 | weak positive | ConsistencyScore™ Generally Consistent | 1 study

Why this answer: This answer is based on a single supporting study.

Limitations

Only one supporting study is available.
Population details are unavailable.

View Full Evidence

Does Melatonin affect bmi?

Moderate Evidence

Melatonin appears to improve BMI.

ConsistencyScore™: Results are consistent across studies.

Ranked evidence signals

1
BMI
EvidenceScore™ Moderate | EvidenceScore™ 69.0 | strong positive | ConsistencyScore™ Consistent | 1 study

Why this answer: This answer is based on a single supporting study.

Limitations

Only one supporting study is available.
Population details are unavailable.

View Full Evidence

Does Melatonin affect body weight?

Moderate Evidence

Melatonin appears to improve Body weight.

ConsistencyScore™: Results are consistent across studies.

Ranked evidence signals

1
Body weight
EvidenceScore™ Moderate | EvidenceScore™ 69.0 | strong positive | ConsistencyScore™ Consistent | 1 study

Why this answer: This answer is based on a single supporting study.

Limitations

Only one supporting study is available.
Population details are unavailable.

View Full Evidence

Does Melatonin improve hip circumference?

Moderate Evidence

Melatonin appears to improve Hip circumference.

ConsistencyScore™: Results are consistent across studies.

Ranked evidence signals

1
Hip circumference
EvidenceScore™ Moderate | EvidenceScore™ 69.0 | strong positive | ConsistencyScore™ Consistent | 1 study

Why this answer: This answer is based on a single supporting study.

Limitations

Only one supporting study is available.
Population details are unavailable.

View Full Evidence

Learn how Evidence Intelligence™ works

Next steps

Continue your research

Choose a next path through related evidence topics, Evidence Explorer views, and research summaries.

Evidence topics

Follow the topics this study contributes to.

Weight Loss Evidence Hub HbA1c Reduction Evidence Hub

Explore in Evidence Explorer

Open broader Evidence Explorer views for this relationship.

All studies on Melatonin and HbA1c All studies on Melatonin and BMI All studies on Melatonin and Body weight All studies on Melatonin and Hip circumference

Related research

Read related research summaries.

Melatonin supplementation may improve blood pressure and obesity indicators in type 2 diabetes patients Vildagliptin and Metformin Improve Glycemic Control in Type 2 Diabetes PEG-Loxe improves weight loss and glycemic control in super-obese T2DM patients Greenhabit app improves diabetes outcomes in adults Intermittent Fasting Diet Improves Glycemic Control in Type 2 Diabetes

No ads. No tracking.

Focused on evidence, not advertising.

Secure & private

Your data is always protected.

Always up to date

New studies added every day.