About the research on this page. The studies cited here investigate photobiomodulation (PBM) as a therapeutic modality and the specific wavelengths used in PBM research — not Mito Red Light devices. The wavelengths in our panels were chosen because the peer-reviewed PBM literature supports them. Evidence levels and study counts reflect the broader research base, not studies of our products. See the full methodology note at the bottom of this page.

Red Light Therapy for Metabolic Health: Clinical Evidence & Research

196 StudiesPhotobiomodulation (PBM) Source-linked

What the research shows

Our evidence rating: Low for obesity and diabetes; low for thyroid conditionsUpdated Reviewed by Alexis Cowan, PhD

Metabolic research on light therapy is early. A 2025 meta-analysis of 11 randomized trials (569 people with obesity) found reductions in waist size, weight, BMI, C-reactive protein and insulin resistance, but no change in body fat percentage (Sun 2025). In type 2 diabetes, a 2025 systematic review found inconsistent, mostly short-term effects on blood sugar, inflammation and nerve function, with low certainty (Wevers 2025), and a 2026 review rated the glycemic evidence very low to low certainty (da Rocha 2026). In healthy adults, 15 minutes of 670 nm light before a glucose drink reduced the rise in blood sugar by 27.7% (Powner 2024).

For Hashimoto's thyroiditis, a 2026 review of 6 human studies found lower thyroid antibodies and lower thyroid hormone medication needs, but most studies also gave selenium or vitamin D, and sham-controlled trials are lacking (Berisha-Muharremi 2026).

Based on 196 indexed studies in this category, 50 of them in people. These studies test photobiomodulation in general, not Mito Red Light devices.

Evidence by condition

Number of studies in our database for each condition. Direction and certainty are shown only where a meta-analysis or systematic review reports them; otherwise the row says "not graded".

ConditionHuman randomized trialsAll human studiesDirection of resultsCertainty
Hypothyroidism 7 10 Lower antibodies and medication needs
Berisha-Muharremi 2026 (PMID 41977196)
Limited; concurrent supplements
Glycemia 2 5 Not graded Not graded
Microbiome 0 3 Not graded Not graded

Key studies: Metabolic Health

The strongest human evidence: systematic reviews and meta-analyses first, then the newest randomized trials. Each card comes straight from our study database and links to the paper.

Meta-analysis

Effects of Photobiomodulation on Metabolic, Inflammatory, and Neurological Outcomes in Type 2 Diabetes: A Systematic Review and Meta-Analysis

et al., Int J Mol Sci, 2025. PMID 41516314

Key finding (checked against the abstract)Randomized trials in type 2 diabetes. Inconsistent, mostly short-term effects on blood sugar, inflammation and nerve function; small periodontal benefits. Low certainty.
Meta-analysis

Effectiveness of photobiomodulation therapy in improving health indicators in obese patients: a systematic review and meta-analysis of RCTs

et al., BMC Complement Med Ther, 2025. PMID 40217252

Key finding (checked against the abstract)11 randomized trials, 569 people with obesity. Lower waist size (MD -7.3 cm), weight (-3.5 kg), BMI, CRP and HOMA-IR; no significant change in body fat percentage or insulin.
Population
Human
Systematic review

Photobiomodulation Therapy to Improve Glycemic Control in People with Diabetes Mellitus: A Systematic Review

et al., Photobiomodul Photomed Laser Surg, 2026. PMID 41858223

Key finding (checked against the abstract)Systematic review in diabetes. Light was associated with lower fasting glucose, post-meal glucose and HbA1c. Very low to low certainty.
Systematic review

Photobiomodulation Therapy in Chronic Autoimmune Thyroiditis: A Systematic Review of Molecular Mechanisms and Clinical Applications

et al., Int J Mol Sci, 2026. PMID 41977196

Key finding (checked against the abstract)6 human studies in chronic autoimmune thyroiditis. Lower antibodies, better hormone levels and lower medication needs, but limited by concurrent supplements and few sham controls.
Population
Review
Human study

Evaluation of Thyroid Volume Normalisation in Female Patients with Hashimoto Thyroiditis: A 12-Month Comparative Study of Combined Supplements and Photobiomodulation Versus Supplementation Alone

et al., Biomedicines, 2025. PMID 40722630

Key finding (checked against the abstract)12-month comparative study, 98 women with Hashimoto's thyroiditis. 820 nm light plus supplements improved thyroid volume, TSH, antibodies and medication dose more than supplements alone.
Population
Human: 98 participants (97 completed); non-randomized study, controlled; 3-week treatment -> 12-month follow-up
Wavelength
820nm
Dose
32 J/cm²
RCT

Light stimulation of mitochondria reduces blood glucose levels

et al., J Biophotonics, 2024. PMID 38378043

Key finding (checked against the abstract)Healthy adults. 15 minutes of 670 nm light reduced the blood sugar rise after a glucose drink by 27.7% over 2 hours.
Population
Human: 30 participants; randomized trial, sham-controlled; single control session -> single intervention session
Wavelength
670nm

Studies that found no effect

Not every trial is positive. "No effect" means the main outcome did not differ from sham or control. "Mixed" means some outcomes improved but the outcome named here did not differ.

YearStudyDesignResultOutcome with no difference
2025 Cardio-metabolic health and sleep quality in adults at risk for Type 2 Diabetes using the Fos Biomedical Non-Transdermal Patch System via photo-biomodulation: A randomized, placebo-controlled crossover trial RCT, n = 39 No effect HbA1c (primary outcome) versus placebo; endothelial function was lower with the patch
2025 Effectiveness of photobiomodulation therapy in improving health indicators in obese patients: a systematic review and meta-analysis of RCTs Meta-analysis Mixed Waist-to-hip ratio, body fat percentage and insulin (waist and weight improved)

Latest human studies: Metabolic Health

The 25 most recent human studies in our database for this category.

YearStudyDesignPopulation
2026 Feasibility of Multi-Wavelength LED Irradiation on the Skull and Preliminary Glycemic Outcomes in Individuals with Type 2 Diabetes: A Prospective Pilot Study. Human study Human
2026 Comparative Effects of Photobiomodulation Therapy Versus Conventional Antioxidant Supplementation on Serum Glutathione Levels in Euthyroid Chronic Autoimmune Thyroiditis: A Prospective Open-Label Interventional Clinical Trial. Human study Human
2026 Effects of Vascular Photobiomodulation on Glycemic Control in Patients With Type II Diabetes Mellitus: A Prospective Single-Arm Clinical Study Single-arm study, n = 15 Human: Single-arm study; 15 participants
2026 Associations of wearable photobiomodulation device use with mitochondrial bioenergetics and fatigue in athletes and individuals with chronic fatigue Single-arm study, n = 20 Human: Single-arm study; 20 participants (10 athletes + 10 chronic fatigue)
2026 The effect of photobiomodulation therapy on fatigue and behavioural status in patients with Hashimoto's thyroiditis RCT, n = 66 Human: 66 participants (60 completed); randomized trial, sham-controlled; 3 weeks
2025 Infrared imaging and intravascular laser irradiation of blood therapy for glycemic control in type 2 diabetes mellitus: a technical note Human study Human: case report
2025 Effectiveness of 808 nm Near Infrared (NIR) Laser Photobiomodulation for Accelerating Postoperative Wound Healing Human study, n = 10 Human: 10 participants; non-randomized study, controlled; 5 days
2025 Photobiomodulation Acutely Augments Resting Metabolism in Women with Obesity RCT, n = 32 Human: 32 participants (16 obese, 16 normal-wt); randomized trial, crossover, sham-controlled; two conditions, single session per condition, 1-week washout
2025 Photobiomodulation with IR and RED light acutely applied to lipedema patients: preliminary study with 3 cases Case series, n = 3 Human: 3 participants; case series
2025 Evaluation of Thyroid Volume Normalisation in Female Patients with Hashimoto Thyroiditis: A 12-Month Comparative Study of Combined Supplements and Photobiomodulation Versus Supplementation Alone Human study, n = 98 Human: 98 participants (97 completed); non-randomized study, controlled; 3-week treatment -> 12-month follow-up
2025 Cardio-metabolic health and sleep quality in adults at risk for Type 2 Diabetes using the Fos Biomedical Non-Transdermal Patch System via photo-biomodulation: A randomized, placebo-controlled crossover trial RCT, n = 39 Human: 39 participants; randomized trial; 12 weeks
2024 High-Intensity Laser Therapy - An Option for Managing the Pain in Anal Fissures Human study, n = 38 Human: 38 patients; retrospective study
2024 The effect of photobiomodulation on histamine and Mucuna pruriens-induced pruritus, hyperknesis and alloknesis in healthy volunteers: A double-blind, randomized, sham-controlled study RCT, n = 17 Human: 17 participants; randomized trial, double-blind; single session
2024 The effect of low-level laser therapy on the oxidative stress level and quality of life in patients with Hashimoto's thyroiditis RCT, n = 46 Human: 46 participants; randomized trial, sham-controlled; 3-week treatment -> 3-month follow-up
2024 Light stimulation of mitochondria reduces blood glucose levels RCT, n = 30 Human: 30 participants; randomized trial, sham-controlled; single control session -> single intervention session
2024 Effective Treatment of Solitary Rectal Ulcer Syndrome by Using Photobiomodulation Therapy: A Case Report Human study Human: case report
2023 Photobiomodulation therapy with light-emitting diode in stimulating adipose tissue mitochondria Human study, n = 8 Human: 8 participants; non-randomized study, self-controlled; ~4-week treatment
2023 Dose and time-response effect of photobiomodulation therapy on glycemic control in type 2 diabetic patients combined or not with hypoglycemic medicine: A randomized, crossover, double-blind, sham-controlled trial RCT, n = 10 Human: 10 participants; randomized trial, crossover (6 conditions), double-blind
2023 Photobiomodulation Therapy as an Adjuvant Treatment of Cervicofacial Liposuction Complications Case series, n = 2 Human: 2 cases; case series; single treatment -> 3-day follow-up
2022 Modulation of the autonomic nervous system by one session of spinal low-level laser therapy in patients with chronic colonic motility dysfunction Single-arm study, n = 41 Human: 41 participants; single-arm study; single session
2022 Effects of LED photobiomodulation therapy on the subcutaneous fatty tissue of obese individuals - histological and immunohistochemical analysis Human study Human: non-randomized study, self-controlled
2022 Effect of laser biostimulation and a low-calorie diet vs. a low-calorie diet alone on insulin resistance, inflammatory biomarkers, and depression among obese postmenopausal women: a randomized controlled trial RCT, n = 66 Human: 66 participants; randomized trial; 12 weeks
2022 Microbiome Changes in Humans with Parkinson's Disease after Photobiomodulation Therapy: A Retrospective Study Single-arm study, n = 12 Human: 12 participants; single-arm trial; 12-week treatment
2022 Modifying the Microbiome as a Potential Mechanism of Photobiomodulation: A Case Report Human study Human: case report
2021 The Effect of Laser Therapy Along With Mediterranean Diet Versus Mediterranean Diet Only on Older Adults With Non-alcoholic Fatty Liver Disease: A Randomized Clinical Trial RCT, n = 60 Human: 60 participants; randomized trial; 12 weeks

What the evidence does not show

  • Less body fat percentage: no significant change across 11 obesity trials (Sun 2025, PMID 40217252).
  • Consistent blood sugar control in type 2 diabetes: effects were inconsistent and short-term (Wevers 2025, PMID 41516314).
  • Thyroid benefits from light alone: most studies combined light with selenium or vitamin D (Berisha-Muharremi 2026, PMID 41977196).

Frequently asked questions

Does red light therapy help with weight loss?

A 2025 meta-analysis of 11 trials found modest reductions in waist size (about 7 cm), weight and BMI, but no change in body fat percentage (Sun 2025).

Does it lower blood sugar?

In a small study of healthy adults, 670 nm light reduced the blood sugar rise after a glucose drink by 27.7% (Powner 2024). In diabetes, effects have been inconsistent and the evidence is low certainty (Wevers 2025; da Rocha 2026).

Does it help Hashimoto's thyroiditis?

Six human studies reported lower antibodies and medication needs, but most also used supplements and sham-controlled trials are needed (Berisha-Muharremi 2026).

Browse All Metabolic Health Studies

All 196 studies in this category from our study database, built on the PBM Research Database by Vladimir Heiskanen.

Search every study across all categories: Open the Full Evidence Explorer →

Methodology & important context

The published research indexed and referenced on this page studies photobiomodulation (PBM) as a therapeutic modality and the specific wavelengths used in those studies — not Mito Red Light devices specifically. The wavelengths used across our panels were chosen because the peer-reviewed PBM literature supports them: this is where published evidence is deepest, where dosing parameters have been characterized in human studies, and where clinical guidelines (such as WALT for inflammation and pain) exist. Mito Red Light has not funded or conducted registered clinical trials on our specific devices, and the study counts referenced here reflect the broader PBM research base — not studies of our products.

Where review authors graded certainty (for example with GRADE), we report their grade; other ratings are Mito’s summary. Study counts reflect peer-reviewed photobiomodulation research drawn from major scientific literature databases, peer-reviewed journals, and other published research repositories. PBM response varies meaningfully by person, tissue, condition, dose, wavelength, and session timing; outcomes reported in the published literature may not be replicable for every user. Mito Red Light devices are not intended to diagnose, treat, cure, or prevent any disease. If you have a medical condition or are under a physician’s care, please consult your healthcare provider before beginning any photobiomodulation regimen.