# Rubus parviflorus (Thimbleberry)

**Canonical URL:** https://ingredients.hermeticasuperfoods.com/ingredients/rubus-parviflorus
**Data Source:** Hermetica Superfoods Ingredient Encyclopedia
**Updated:** 2026-03-30
**Evidence Score:** 2 / 10
**Category:** Herb
**Also Known As:** Rubus parviflorus, Western thimbleberry, White-flowering raspberry, Salmonberry bush, Mountain sorrel berry, Red thimbleberry, Rubus nutkanus

## Overview

Thimbleberry (Rubus parviflorus) is a wild-harvested North American berry containing anthocyanins and ellagitannins that exert antioxidant activity primarily through [free radical scaveng](/ingredients/condition/antioxidant)ing and inhibition of lipid peroxidation. No human clinical trials have specifically studied R. parviflorus, so its health effects are extrapolated from related Rubus species research.

## Health Benefits

• No specific health benefits for R. parviflorus are clinically documented - evidence quality: absent
• Related Rubus species show potential for menopause symptom relief based on one RCT with R. coreanus - evidence quality: preliminary
• Genus-wide [antioxidant](/ingredients/condition/antioxidant) properties suggested from in vitro studies on phenolic compounds - evidence quality: preliminary
• Traditional use for wound healing and digestive support by Indigenous peoples - evidence quality: traditional only
• Potential [anti-inflammatory](/ingredients/condition/inflammation) effects inferred from related Rubus species - evidence quality: preliminary

## Mechanism of Action

Thimbleberry's primary bioactive compounds — anthocyanins such as cyanidin-3-glucoside and ellagitannins including sanguiin H-6 — neutralize [reactive oxygen species](/ingredients/condition/antioxidant) (ROS) by donating hydrogen atoms to free radicals, inhibiting lipid peroxidation via suppression of NADPH oxidase activity. Ellagitannins are metabolized by gut microbiota into urolithins, which may modulate NF-κB signaling pathways to reduce [pro-inflammatory cytokine](/ingredients/condition/inflammation) expression including TNF-α and IL-6. Polyphenolic constituents may also weakly interact with estrogen receptors (ERα and ERβ), a mechanism proposed for menopausal symptom relief observed in related species such as R. coreanus.

## Clinical Summary

No randomized controlled trials or observational studies have been conducted specifically on Rubus parviflorus in human subjects, leaving its clinical evidence base absent. The closest relevant human trial is a single RCT investigating R. coreanus extract for menopausal symptoms, which reported a statistically significant reduction in Kupperman Index scores compared to placebo, though sample size and blinding details limit generalizability. In vitro studies on Rubus genus extracts demonstrate IC50 values for DPPH radical scavenging in the range of 10–50 µg/mL, suggesting meaningful [antioxidant](/ingredients/condition/antioxidant) capacity, but these results do not translate directly to clinical outcomes. Until species-specific human trials are conducted, any health claims for thimbleberry remain speculative and extrapolated from genus-level data.

## Nutritional Profile

Rubus parviflorus (Thimbleberry) nutritional data is primarily derived from fruit composition analysis, with limited published quantitative studies specific to this species. Fresh thimbleberry fruit contains approximately 85-88% water, with carbohydrates as the dominant macronutrient (~10-12g/100g fresh weight), primarily as simple sugars (fructose and glucose) and dietary fiber (~4-6g/100g, predominantly insoluble cellulose and pectin). Protein content is low (~0.8-1.2g/100g), and fat is negligible (<0.5g/100g). Vitamin C content is estimated at 15-30mg/100g based on extrapolation from closely related Rubus species such as R. idaeus (red raspberry), though direct measurement data for R. parviflorus is sparse. Vitamin K and folate are present at minor levels consistent with other Rubus berries. Mineral content includes potassium (~150-200mg/100g estimated), manganese (~0.3-0.6mg/100g), magnesium, and calcium at modest concentrations. The most characterized bioactive compounds are polyphenols: ellagitannins (including ellagic acid, estimated 10-50mg/100g fresh weight by analogy to congeners), anthocyanins (cyanidin-3-glucoside and cyanidin-3-rutinoside as likely dominant forms, estimated 50-150mg/100g), and flavonols such as quercetin glycosides. Leaves contain tannins and flavonoids used traditionally; specific concentrations are undocumented for this species. Bioavailability of ellagitannins is low in native form but gut microbiota convert them to bioavailable urolithins; anthocyanin bioavailability is generally <5% in humans. All quantitative values should be treated as estimates pending species-specific analytical studies.

## Dosage & Preparation

No clinically studied dosages exist for Rubus parviflorus due to absent human trials. Related Rubus coreanus extract was studied at 2000 mg/day (oral, combined with A. membranaceus) for 12 weeks, though this cannot be extrapolated to thimbleberry. Consult a healthcare provider before starting any new supplement.

## Safety & Drug Interactions

Thimbleberry is generally regarded as safe when consumed as a whole food, with no documented serious adverse events in the published literature specific to R. parviflorus. Individuals with known allergies to Rosaceae family plants, including raspberries or blackberries, should exercise caution due to potential cross-reactivity involving shared allergenic proteins. The ellagitannin and polyphenol content theoretically could inhibit CYP3A4 enzyme activity at high concentrated extract doses, potentially altering plasma levels of medications metabolized by this pathway such as statins or certain anticoagulants, though no interaction studies have confirmed this for R. parviflorus specifically. Pregnant and breastfeeding women should limit use beyond normal food amounts, as the weak phytoestrogenic activity observed in related Rubus species has not been assessed for reproductive safety in this species.

## Scientific Research

No human clinical trials, RCTs, or meta-analyses specifically on Rubus parviflorus were found in the research. The only related clinical evidence comes from one RCT (PMID: 35251207) testing Rubus coreanus extract combined with Astragalus membranaceus in 72 postmenopausal women, showing reduced menopause symptoms over 12 weeks.

## Historical & Cultural Context

Rubus parviflorus berries and leaves have been used by Indigenous North American peoples for food and minor medicinal purposes, including as a poultice for wounds or digestive aid. The broader Rubus genus features in European and Asian traditional systems for diarrhea, uterine health, [inflammation](/ingredients/condition/inflammation), and infections, with R. idaeus leaves used as astringents for centuries.

## Synergistic Combinations

Astragalus membranaceus, other Rubus species, [antioxidant](/ingredients/condition/antioxidant) polyphenols, vitamin C, quercetin

## Frequently Asked Questions

### Does thimbleberry have the same benefits as raspberries?

Thimbleberry and red raspberry (Rubus idaeus) share closely related phytochemical profiles, both containing anthocyanins like cyanidin-3-glucoside and ellagitannins, but no head-to-head studies exist comparing their bioavailability or clinical effects. Red raspberry has substantially more research behind it, including studies on its leaf extract for uterine tone. Assuming identical benefits would be scientifically unsupported given differences in exact polyphenol concentrations across species.

### Can thimbleberry help with menopause symptoms?

There is no clinical evidence directly linking R. parviflorus to menopause symptom relief. This extrapolation comes from a single RCT on R. coreanus extract, which showed a reduction in hot flash frequency and Kupperman Index scores, potentially mediated by phytoestrogens binding weakly to estrogen receptor beta (ERβ). Until a trial specifically studies thimbleberry extract in menopausal women, this benefit cannot be confirmed.

### What antioxidants are found in thimbleberry?

Thimbleberry contains anthocyanins — primarily cyanidin-3-glucoside and cyanidin-3-rutinoside — along with ellagitannins such as sanguiin H-6 and lambertianin C, and flavonols including quercetin and kaempferol glycosides. These compounds collectively contribute to DPPH and ABTS radical scavenging activity documented in Rubus genus extracts. The exact quantified polyphenol profile of R. parviflorus specifically has not been fully characterized in peer-reviewed literature.

### Is thimbleberry safe to eat raw?

The ripe fruit of Rubus parviflorus is widely consumed as a traditional food by Indigenous peoples of North America and is considered safe to eat raw with no documented toxicity at normal dietary amounts. The leaves have also been used in traditional preparations, though concentrated leaf extracts have not been assessed for safety in the same way the fruit has. People with Rosaceae plant allergies should be cautious, as shared proteins between thimbleberry and related species like strawberries or raspberries could trigger reactions.

### Are there any thimbleberry supplements available and what dose is recommended?

Standardized thimbleberry supplements are not widely commercially available, and no clinically established dosage exists for R. parviflorus in any form. Rubus genus supplements on the market are typically standardized for raspberry ketones or red raspberry leaf extract at doses ranging from 100–500 mg daily, but these are distinct species and formulations. Without human pharmacokinetic data for thimbleberry specifically, no evidence-based dosage recommendation can be made.

### What is the difference between thimbleberry leaf and thimbleberry fruit supplements?

Thimbleberry supplements are typically made from either the fruit or the leaves, with traditional preparations favoring the leaves for their use in herbal teas and tinctures. The fruit is more commonly consumed fresh or in food products due to its palatability, while leaf extracts have been traditionally used in folk medicine for various purposes. Nutritional profiles differ between these forms, with leaves potentially concentrating certain compounds during drying, though direct comparative research on their efficacy is limited. The choice between forms often depends on intended use and availability rather than established superiority of one over the other.

### Is thimbleberry safe to take with blood thinners or anticoagulant medications?

While thimbleberry contains phenolic compounds with potential mild antioxidant activity, there is no clinical evidence documenting significant interactions with blood thinners or anticoagulants like warfarin or apixaban. However, individuals taking these medications should consult their healthcare provider before adding any new supplement, as the Rubus genus contains compounds that theoretically could affect platelet function in high concentrations. Current evidence does not contraindicate thimbleberry use with anticoagulants, but personalized medical guidance is recommended due to limited safety studies in this population.

### Why is there more research on other Rubus species than on thimbleberry specifically?

Clinical research has focused primarily on other Rubus species like R. coreanus (Korean black raspberry) and R. idaeus (red raspberry) because they are more widely cultivated, commercially available, and have established traditional use in Asian and European medicine. Thimbleberry (R. parviflorus) is less common in global commerce and is primarily foraged in North America, making it less attractive for pharmaceutical and supplement researchers seeking large populations for studies. As a result, most evidence supporting Rubus genus health claims comes from species other than thimbleberry, and direct clinical evidence specific to R. parviflorus remains absent.

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*Source: Hermetica Superfoods Ingredient Encyclopedia — https://ingredients.hermeticasuperfoods.com*
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