Raspberry Rubus Idaeus
Also known as: Raspberry, Red Raspberry, Rubus idaeus L., Rubus idaeus
Overview
Rubus idaeus, commonly known as Raspberry or Red Raspberry, is a fruit-bearing plant whose fruit and leaves are utilized in traditional medicine and as dietary supplements. It is categorized as a botanical supplement and fruit extract. Primary areas of research interest include its potential impact on metabolic health, particularly lipid profiles and glucose regulation, as well as its traditional use for pregnancy-related uterine effects, and its general antioxidant properties. While research on Rubus idaeus is ongoing, involving in vitro, animal, and some human clinical studies, the overall maturity of evidence is moderate. High-quality human randomized controlled trials (RCTs) and meta-analyses are limited, and existing studies often report mixed or inconclusive results regarding significant clinical effects.
Benefits
Clinical benefits of Rubus idaeus are largely limited and inconsistent. A recent systematic review and meta-analysis of 11 RCTs found no significant effect of raspberry consumption on blood pressure (systolic or diastolic) or lipid profile markers (total cholesterol, triglycerides) in adults. While some preliminary and inconsistent RCT data suggest possible modulation of glucose and insulin responses, this evidence is not robust. Traditionally, raspberry leaf has been used to influence uterine contractility; however, a systematic review of 13 studies (animal and human) revealed mixed evidence. While some laboratory and animal studies showed uterine effects, human RCT evidence is sparse and inconclusive regarding both efficacy and safety for this purpose. Overall, clinical effect sizes for Rubus idaeus are generally small or non-significant, and robust evidence for specific health benefits is not well-established.
How it works
Rubus idaeus contains various bioactive compounds, including polyphenols, flavonoids, and anthocyanins, which are known for their antioxidant properties. The proposed mechanisms of action primarily involve antioxidant activity and the modulation of inflammatory pathways. In the context of its traditional use, particularly raspberry leaf, there is a suggested effect on smooth muscle contractility, specifically in the uterus. However, the exact molecular targets and pathways in humans are not well-defined, with most mechanistic data derived from in vitro and animal models. The bioavailability of these active compounds can vary significantly, influenced by factors such as the specific formulation (e.g., tea, extract, capsule) and individual metabolic differences, which can impact their absorption and overall effectiveness in the body.
Side effects
Rubus idaeus, both the fruit and the leaf, is generally considered safe for consumption when used as food or in typical supplemental amounts. Major adverse effects have not been widely reported in clinical trials or observational studies. Allergic reactions are possible but appear to be rare. Data regarding drug interactions are limited, suggesting a low risk, but caution is always advised when combining supplements with medications. Specific caution is recommended during pregnancy due to the traditional use of raspberry leaf for its potential uterine effects, although strong evidence of harm from typical dietary intake is lacking. High-dose supplementation during pregnancy should only be undertaken under medical supervision due to the inconclusive evidence regarding its efficacy and safety in this context.
Dosage
There is no standardized or universally established dosing regimen for Rubus idaeus due to the variability in preparations and the lack of robust clinical data. Studies have utilized a wide range of doses, commonly ranging from 1 to 2 grams of dried leaf or fruit extract daily. However, the optimal dosage for any specific purpose remains unclear. The timing of administration and the form of the supplement (e.g., tea, extract, capsule) can significantly influence the absorption and potential effects of the active compounds. Due to the limited clinical evidence, specific upper limits or safety thresholds for high-dose supplementation have not been definitively established, and users should exercise caution and consult healthcare professionals.
FAQs
Is raspberry leaf effective for labor induction?
Current evidence is insufficient and inconclusive to recommend raspberry leaf for inducing labor or shortening labor duration. More rigorous human trials are needed to confirm any such effects.
Does raspberry improve cholesterol or blood pressure?
Recent meta-analyses of randomized controlled trials indicate that raspberry consumption has no significant effect on blood pressure or lipid profile markers like total cholesterol and triglycerides.
Is Rubus idaeus safe during pregnancy?
While generally considered safe in dietary amounts, high-dose raspberry leaf supplements during pregnancy should be used cautiously and only under medical supervision due to mixed evidence regarding uterine effects.
Research Sources
- https://pmc.ncbi.nlm.nih.gov/articles/PMC7871383/ – This systematic review, including 13 studies (animal and human), investigated the effects of raspberry leaf on uterine activity. It found mixed evidence, with some laboratory and animal studies showing uterine effects, but human RCT evidence was sparse and inconclusive regarding efficacy and safety for pregnancy-related uses. The review highlighted the need for more robust human trials.
- https://onlinelibrary.wiley.com/doi/10.1002/fsn3.3940 – This meta-analysis of 11 randomized controlled trials (n>500 adults) assessed the impact of raspberry consumption on cardiovascular risk factors. It concluded that raspberry intake had no significant effect on blood pressure (systolic or diastolic) or lipid profile markers (total cholesterol, triglycerides), indicating limited clinical benefits in these areas.
- https://academic.oup.com/cdn/article/3/Supplement_1/nzz031.OR29-03-19/5518230 – This research, presented as an abstract, describes an acute intervention RCT investigating the effects of raspberry on glucose and insulin responses. It suggested possible modulation of these markers but noted that the data were preliminary and inconclusive, likely due to a small sample size and acute study design, warranting further investigation.
