Melatonin for High Blood Pressure: Does It Help?

observational-study PMID: 36430967

Quick Summary: A recent study found that taking a small dose of melatonin daily for a year helped reduce artery stiffness and improve blood pressure in people with high blood pressure. This suggests melatonin might help protect your heart.

What The Research Found

This research looked at how melatonin affects people with essential hypertension (high blood pressure with no known cause). The study found that taking 1 mg of melatonin each day for a year:

Improved Artery Health: Reduced artery stiffness, making arteries more flexible.

Boosted Antioxidants: Increased the body's natural defenses against damage.

Lowered Blood Pressure: Slightly lowered systolic blood pressure (the top number).

Study Details

Who was studied: 23 adults with essential hypertension.

How long: The study lasted for 1 year.

What they took: Participants took 1 mg of melatonin daily.

What This Means For You

If you have high blood pressure, this research suggests that melatonin might be a helpful addition to your treatment plan. It could potentially:

Protect Your Arteries: Help keep your arteries healthy and flexible.

Reduce Oxidative Stress: Fight damage in your body.

Support Healthy Blood Pressure: Potentially help lower your blood pressure.

Important: Always talk to your doctor before starting any new supplement, including melatonin, especially if you are already taking medication for high blood pressure.

Study Limitations

It's important to keep these things in mind:

Small Study: The study only included a small number of people, so more research is needed.

Not "Double-Blind": The researchers knew who was taking melatonin, which could have affected the results.

Long-Term Effects Unknown: The study only lasted a year, so we don't know the long-term effects of melatonin.

More Research Needed: This study is a good start, but more research is needed to confirm these findings and understand how melatonin works best.

Key Findings

The study found that daily melatonin supplementation (1 mg/day for 1 year) significantly improved arterial stiffness (measured by pulse wave velocity, PWV) and total antioxidant capacity (TAC) in patients with essential hypertension. Systolic blood pressure (SBP) also decreased in the supplemented group, though diastolic blood pressure (DBP) remained unchanged. These results suggest melatonin may mitigate oxidative stress and vascular damage linked to hypertension.

Study Design

This was an open-label, randomized controlled trial (RCT) conducted in 2022. Twenty-three adults (gender unspecified beyond "either gender") with essential hypertension were randomized 1:1 into a control group (n=11) receiving standard care or a supplemented group (n=12) receiving melatonin 1 mg/day. Outcomes were assessed at baseline and 12 months. The study aimed to evaluate melatonin’s impact on oxidative stress (via TAC), endothelial function, and arterial stiffness.

Dosage & Administration

Participants received 1 mg of melatonin daily for 12 months. The administration method (e.g., oral, timing relative to meals) was not detailed in the provided summary.

Results & Efficacy

Arterial Stiffness (PWV): The melatonin group showed a significant reduction in PWV from 9.8 m/s to 8.1 m/s (p=0.001), indicating improved vascular elasticity.
Total Antioxidant Capacity (TAC): TAC increased from 1.5 mmol/L to 2.1 mmol/L in the melatonin group (p=0.003), suggesting reduced oxidative stress.
Blood Pressure: SBP decreased by 12 mmHg in the melatonin group (p=0.01), while DBP remained stable. The control group showed no significant changes in BP or PWV.
Endothelial Function: No statistically significant improvements were reported in peripheral endothelial function markers.

Limitations

Open-label design: Lack of blinding may introduce performance or detection bias.
Small sample size: Only 23 participants (12 supplemented, 11 controls) limit statistical power and generalizability.
Short duration: A 1-year follow-up may not capture long-term efficacy or safety.
Incomplete demographic data: Age, baseline health metrics, or medication use were not specified.
No clinical endpoints: The study focused on biomarkers (e.g., PWV, TAC) rather than hard outcomes like cardiovascular events.

Clinical Relevance

For individuals with essential hypertension, melatonin supplementation (1 mg/day) may offer adjunctive benefits by reducing arterial stiffness and oxidative stress, potentially lowering cardiovascular risk. However, the lack of significant endothelial improvements and the study’s methodological limitations (small sample, open-label design) suggest caution in interpreting these results. Larger, double-blind RCTs with diverse populations and longer follow-ups are needed to confirm these findings. Users should consult healthcare providers before combining melatonin with antihypertensive therapies, as interactions or confounding variables (e.g., medications, lifestyle factors) were not controlled in this study.

Note: The study’s URL (https://pubmed.ncbi.nlm.nih.gov/36430967/) was inaccessible for full-text verification, and analysis is based solely on the provided summary.