Hawthorn Flower And Leaf Extract
Also known as: Crataegus monogyna, Crataegus laevigata, Hawthorn flower and leaf extract, Hawthorn, Crataegus spp.
Overview
Hawthorn flower and leaf extract is a herbal supplement derived from the leaves and flowers of the hawthorn plant (Crataegus species), primarily Crataegus monogyna and Crataegus laevigata. It is rich in bioactive compounds such as flavonoids, oligomeric procyanidins, and polyphenols, which contribute to its therapeutic effects. This extract is predominantly utilized as an adjunctive treatment for various cardiovascular conditions, most notably chronic heart failure and hypertension. Its key characteristics include potent antioxidant, vasodilatory, and cardioprotective properties. Research on hawthorn extract is extensive, with a moderate to high level of maturity, supported by numerous randomized controlled trials (RCTs) and meta-analyses. The quality of evidence is generally strong, with well-conducted double-blind, placebo-controlled RCTs and systematic reviews affirming its efficacy and safety profile.
Benefits
Hawthorn flower and leaf extract offers several evidence-based benefits, primarily for cardiovascular health: - **Chronic Heart Failure:** Strong evidence from meta-analyses of randomized controlled trials (RCTs) indicates that hawthorn extract significantly improves cardiac function in patients with chronic heart failure (NYHA I-III). Studies show improvements in maximal workload (e.g., by 7 Watts, 95% CI: 3 to 11; p<0.01) and a reduction in the pressure-heart rate product, signifying enhanced cardiac efficiency. Patients also report significant reductions in symptoms like dyspnea and fatigue compared to placebo. These benefits are typically observed with daily doses between 160 mg and 1800 mg over 3 to 24 weeks. - **Blood Pressure Regulation:** Meta-analyses suggest a statistically significant, albeit modest, reduction in systolic blood pressure. The effects on diastolic pressure are less consistent. While clinically meaningful, the effect size can be heterogeneous across studies. - **Cardiovascular Protection:** Preclinical and clinical data indicate that hawthorn extracts contribute to overall cardiovascular protection. This includes reducing serum lipid levels, inhibiting cholesterol absorption and synthesis, mitigating oxidative stress, and improving endothelial function. These actions collectively may slow the progression of atherosclerosis and improve vascular health.
How it works
Hawthorn's therapeutic effects stem from its rich content of bioactive compounds, primarily flavonoids and oligomeric procyanidins. These compounds exert their effects through several mechanisms. They act as potent antioxidants and free radical scavengers, thereby reducing oxidative damage to myocardial cells. Hawthorn also exhibits anti-inflammatory properties by inhibiting human neutrophil elastase, which helps reduce inflammation and protect against ischemic injury. Its vasodilatory effects improve coronary blood flow, leading to reduced cardiac workload and improved oxygen supply to the heart. Furthermore, hawthorn contributes to lipid-lowering by inhibiting intestinal lipid absorption, suppressing hepatic cholesterol synthesis, and promoting cholesterol efflux from macrophages, which helps prevent foam cell formation and atherosclerotic plaque development. These combined actions improve overall cardiac function and vascular health.
Side effects
Hawthorn extract is generally well-tolerated, with a low incidence of adverse effects reported in clinical trials. Common side effects, occurring in less than 5% of users, are typically mild and transient. These may include mild gastrointestinal symptoms such as nausea, dizziness, and occasional transient cardiac complaints like palpitations or bradycardia. Serious adverse events are rare. While no significant drug interactions or contraindications have been consistently reported, caution is advised when hawthorn extract is used concurrently with conventional cardiovascular medications, such as digoxin, beta-blockers, calcium channel blockers, or nitrates. This is due to the potential for additive effects, which could theoretically lead to hypotension or bradycardia. Patients on such medications should consult their healthcare provider before starting hawthorn. There is insufficient data to establish the safety of hawthorn extract in special populations, including pregnant or lactating women, and therefore its use is generally not recommended in these groups without medical supervision. Individuals with pre-existing heart conditions should always consult a physician before using hawthorn, as it is intended as an adjunctive therapy and not a replacement for prescribed medications.
Dosage
Effective dosages of hawthorn flower and leaf extract, as observed in clinical trials, typically range from 160 mg to 1800 mg per day. These doses refer to standardized extracts, such as WS 1442 or LI 132, which have a defined content of active compounds like oligomeric procyanidins. The extract is usually administered orally, often in divided doses throughout the day. The duration of treatment in studies commonly spans from 3 to 24 weeks, with benefits often becoming apparent within weeks to a few months of consistent use. For optimal consistency and efficacy, standardized extracts are preferred. There is no established maximum safe dose beyond the ranges tested in clinical trials; therefore, doses exceeding these ranges should be approached with caution and under professional guidance. The absorption of hawthorn's active compounds can be influenced by the formulation, with hydroalcoholic extracts being a common and effective form.
FAQs
Is hawthorn extract safe for long-term use?
Evidence supports the safety of hawthorn extract for up to 24 weeks of use. While longer-term data are limited, no major safety concerns have emerged from available research, suggesting a generally favorable safety profile.
Can hawthorn replace conventional heart failure medications?
No, hawthorn extract is intended as an adjunctive therapy to complement conventional heart failure medications, not to replace them. Patients should always consult their doctor before making any changes to their prescribed treatments.
When are benefits seen?
Improvements in symptoms and cardiac function with hawthorn extract are typically observed within a few weeks to several months of consistent treatment, depending on the individual and the specific condition being addressed.
Does hawthorn lower blood pressure?
Yes, hawthorn extract has been shown to modestly lower systolic blood pressure. However, its effects on diastolic blood pressure are less consistent, and the overall blood pressure-lowering effect can vary among individuals.
Research Sources
- https://pubmed.ncbi.nlm.nih.gov/12798455/ – This meta-analysis of 8 randomized controlled trials (n=632) found that hawthorn extract significantly improved maximal workload by 7 Watts and reduced the pressure-heart rate product in patients with chronic heart failure (NYHA I-III). It also improved symptoms like dyspnea and fatigue, with mild adverse events reported. The study highlights hawthorn's efficacy as an adjunctive therapy for heart failure.
- https://pmc.ncbi.nlm.nih.gov/articles/PMC12298042/ – This meta-analysis investigated the effect of hawthorn on blood pressure, concluding that it significantly reduced systolic blood pressure but had less clear effects on diastolic pressure. The study noted heterogeneity across trials and suggested the need for larger, more robust studies to confirm the findings and understand the variability.
- https://www.thieme-connect.com/products/ejournals/pdf/10.1055/s-0030-1270849.pdf – This comprehensive review and meta-analysis, involving over 4000 patients from multiple RCTs, confirmed that standardized hawthorn extracts (WS 1442 and LI 132) significantly improve heart failure symptoms, left ventricular ejection fraction (LVEF), and overall cardiac efficiency. It provides strong evidence for hawthorn's role in managing chronic heart failure.
- https://www.frontiersin.org/journals/pharmacology/articles/10.3389/fphar.2020.00118/full – This research explores the cardiovascular protective effects of hawthorn, detailing its mechanisms including reduction of serum lipid levels, inhibition of cholesterol absorption and synthesis, reduction of oxidative stress, and improvement of endothelial function. It suggests hawthorn's potential in slowing atherosclerosis progression and improving vascular health.
- https://www.aafp.org/pubs/afp/issues/2010/0215/p465.html – This article provides an overview of hawthorn's uses, mechanisms, and safety profile, particularly in the context of heart failure. It emphasizes hawthorn's antioxidant and vasodilatory properties and generally good tolerability, while also advising caution regarding potential interactions with cardiovascular medications.