Black Walnut Leaf Glycerite Liquid Extract
Also known as: Black walnut leaf extract, Walnut leaf glycerite liquid extract, Juglans regia leaf extract
Overview
Juglans regia leaf extract is a botanical supplement derived from the leaves of the walnut tree. The glycerite liquid extract form is a tincture prepared by extracting active compounds in glycerin, which helps preserve water-soluble constituents. Traditionally, walnut leaves have been used for various medicinal purposes. Current research primarily focuses on its potential role in managing glycemic control in individuals with type 2 diabetes mellitus (T2DM) and its possible, though less substantiated, effects on lipid profiles. While the research maturity is moderate, with several randomized controlled trials (RCTs) and a recent systematic review/meta-analysis available, the quality of evidence is limited by the number and sample sizes of the RCTs. Despite some heterogeneity, meta-analyses provide pooled data supporting its use for certain conditions. It is important to note that while the extract contains beneficial phytochemicals, robust clinical data for all proposed benefits are still emerging.
Benefits
The primary evidence-based benefit of *Juglans regia* leaf extract is its potential to improve glycemic control in individuals with type 2 diabetes mellitus (T2DM). A meta-analysis of four randomized controlled trials (RCTs) involving 195 participants demonstrated significant reductions in fasting blood glucose (weighted mean difference [WMD] −18.04 mg/dL; 95% CI −32.88 to −3.21; p=0.017) and an increase in fasting insulin levels (WMD 1.93 U/L; 95% CI 0.40 to 3.45; p=0.014). While no overall significant effect on HbA1c was observed, studies with intervention durations longer than 8 weeks showed a significant reduction (WMD −0.64%; 95% CI −1.16 to −0.11; p=0.018). The evidence for these glycemic benefits is considered moderate, primarily applicable to adults with T2DM. Conversely, the same meta-analysis found no significant changes in lipid parameters (total cholesterol, LDL, HDL, triglycerides), indicating a lack of robust evidence for lipid-lowering effects. Secondary effects such as antioxidant and anti-inflammatory properties are suggested by the extract's phytochemical content, but these lack strong clinical validation.
How it works
*Juglans regia* leaf extract contains various bioactive compounds, including polyphenols, flavonoids, and juglone. These constituents are believed to exert their effects through several proposed mechanisms. They may contribute to antioxidant activity by neutralizing free radicals and reducing oxidative stress, which is often implicated in chronic diseases like diabetes. Additionally, the extract is thought to possess anti-inflammatory properties, potentially modulating inflammatory pathways in the body. In the context of glycemic control, the compounds are hypothesized to improve insulin sensitivity and modulate glucose metabolism pathways, leading to better blood sugar regulation. However, the exact molecular targets and specific biological pathways involved are still under investigation, and the bioavailability of these compounds can vary depending on the extraction method.
Side effects
*Juglans regia* leaf extract appears to have a favorable safety profile when used at studied doses (100–750 mg/day) for short to medium durations (8–12 weeks). Clinical trials have generally reported mild or absent side effects, and no common adverse reactions are well documented in the literature. Importantly, no significant drug interactions have been reported in the reviewed studies, suggesting a low risk of adverse interactions with conventional medications. However, there is insufficient data regarding its safety in specific populations, such as pregnant or breastfeeding individuals, children, or those with pre-existing medical conditions not included in the studies. Therefore, its use in these groups is not recommended without medical supervision. As with any supplement, individuals should consult a healthcare professional before starting *Juglans regia* leaf extract, especially if they are on medication or have underlying health concerns, to ensure its appropriateness and monitor for any unforeseen reactions.
Dosage
Effective doses of *Juglans regia* leaf extract in clinical trials have ranged from an initial 100 mg/day, increasing up to 200–750 mg/day. These dosages were typically administered for durations of 8 to 12 weeks. For improvements in HbA1c, a longer intervention duration, specifically exceeding 8 weeks, may be necessary to observe significant effects. It is important to note that most clinical studies have utilized hydroalcoholic extracts, and specific dosing guidelines for glycerite liquid extract forms are not yet standardized. Therefore, users of glycerite extracts should follow product-specific instructions or consult a healthcare professional for appropriate dosing. The absorption characteristics and any potential cofactor requirements for optimal efficacy of *Juglans regia* leaf extract are not clearly defined in the current literature.
FAQs
Does it improve cholesterol?
Current meta-analyses have not demonstrated significant lipid-lowering effects, indicating that it does not reliably improve cholesterol levels.
Is it safe?
At studied doses (100–750 mg/day) for up to 12 weeks, *Juglans regia* leaf extract appears safe with no major adverse effects reported in clinical trials.
How long to see benefits?
Glycemic benefits, particularly reductions in fasting glucose, may appear within 8 weeks, but improvements in HbA1c might require longer durations, typically beyond 8 weeks.
Research Sources
- https://pmc.ncbi.nlm.nih.gov/articles/PMC9065396/ – This systematic review and meta-analysis of randomized controlled trials (RCTs) investigated the effects of *Juglans regia* leaf extract on glycemic and lipid profiles in type 2 diabetes mellitus. It found significant reductions in fasting blood glucose and increases in fasting insulin, with HbA1c improvements noted in studies lasting over 8 weeks. No significant changes in lipid parameters were observed.
- https://pubmed.ncbi.nlm.nih.gov/35558998/ – This publication is likely a duplicate or related entry to the first source, focusing on the same meta-analysis. It reinforces the findings of the systematic review regarding the beneficial effects of *Juglans regia* leaf extract on glycemic control in T2DM patients, specifically highlighting reductions in fasting glucose and increases in insulin.
- https://www.ijpsonline.com/articles/insights-of-pharmacological-activities-patents-and-clinical-applications-of-polyphenolic-compounds-enriched-nuts-of-emjuglans-regi-5638.html?view=mobile – This narrative review provides insights into the pharmacological activities, patents, and clinical applications of polyphenolic compounds found in *Juglans regia*. It discusses the antioxidant, anti-inflammatory, and glycemic benefits, noting that while some clinical trials exist, more large-scale RCTs are needed to confirm these effects robustly.
- https://www.koreascience.kr/article/JAKO202230243211078.page – This source appears to be another entry for the same meta-analysis by Mirzababaei et al., 2022. It likely provides further details or an alternative access point to the study that concluded *Juglans regia* leaf extract significantly reduces fasting glucose and increases insulin in T2DM patients, with HbA1c benefits in longer interventions.