# Concord Grape (Vitis labrusca)

**Canonical URL:** https://ingredients.hermeticasuperfoods.com/ingredients/concord-grape
**Data Source:** Hermetica Superfoods Ingredient Encyclopedia
**Updated:** 2026-04-05
**Evidence Score:** 2 / 10
**Category:** Fruit
**Also Known As:** Vitis labrusca, American grape, Fox grape, Labrusca grape, Concord variety, North American grape

## Overview

Concord grape (Vitis labrusca) is rich in anthocyanins, resveratrol isomers, and quercetin that exert antioxidant effects by scavenging free radicals and modulating [oxidative stress](/ingredients/condition/antioxidant) pathways. Preliminary research suggests these polyphenols may support [cardiovascular](/ingredients/condition/heart-health) and [cognitive](/ingredients/condition/cognitive) health, though robust human clinical data remain limited.

## Health Benefits

• Rich in phenolic compounds including anthocyanins and phenolic acids with [antioxidant activity](/ingredients/condition/antioxidant) demonstrated in DPPH, ABTS, and ORAC assays (preliminary evidence only)
• Contains resveratrol isomers in grape skins, though clinical effects not studied
• Source of flavonoids including quercetin, catechin, and rutin (compositional data only, no clinical trials)
• Provides organic acids including tartaric (4.23-6.41 g/L) and malic acid (up to 7.77 g/L) in juice form
• Seeds contain 11% fiber and 3% minerals, though health effects not clinically evaluated

## Mechanism of Action

Anthocyanins in Concord grape skins bind and neutralize [reactive oxygen species](/ingredients/condition/antioxidant) (ROS) through electron donation, measurable via DPPH, ABTS, and ORAC assays, while also inhibiting pro-[inflammatory](/ingredients/condition/inflammation) enzymes such as COX-1 and COX-2. Resveratrol isomers (cis- and trans-resveratrol) activate the SIRT1 deacetylase pathway and modulate NF-κB signaling to attenuate inflammatory gene expression. Quercetin acts as a flavonoid inhibitor of xanthine oxidase and chelates transition metal ions, further reducing oxidative damage at the cellular level.

## Clinical Summary

Most evidence for Concord grape polyphenols comes from in vitro and animal studies demonstrating [antioxidant](/ingredients/condition/antioxidant) capacity; controlled human trials are sparse and small in scale. A handful of pilot studies involving 12–50 adults have examined Concord grape juice (6–12 oz daily for 8–12 weeks), reporting modest improvements in plasma antioxidant status and [endothelial function](/ingredients/condition/heart-health) markers, but these lacked placebo controls or sufficient power to draw firm conclusions. One small randomized crossover study (n=38) found Concord grape juice improved verbal learning scores in older adults with mild [memory](/ingredients/condition/cognitive) decline compared to placebo, though the effect size was limited. Overall, the existing human evidence is preliminary and insufficient to support definitive health claims.

## Nutritional Profile

Concord grapes (Vitis labrusca) per 100g fresh weight: Calories ~67 kcal, Water ~82g, Carbohydrates ~17g (of which sugars ~16g, predominantly glucose and fructose in roughly equal proportions), Dietary fiber ~0.9g, Protein ~0.6g, Fat ~0.4g. Key micronutrients: Vitamin C ~4mg (4-5% DV), Vitamin K ~14.6mcg (~12% DV), Vitamin B6 ~0.09mg, Thiamine ~0.07mg, Riboflavin ~0.07mg, Potassium ~191mg (~4% DV), Copper ~0.04mg, Manganese ~0.07mg, modest amounts of calcium (~10mg) and magnesium (~7mg). Bioactive compounds: Total anthocyanins ~43-160mg/100g fresh weight (predominantly cyanidin-3-glucoside, delphinidin-3-glucoside, petunidin-3-glucoside, and malvidin-3-glucoside), concentrated in the skin; total polyphenols ~100-300mg gallic acid equivalents/100g; quercetin ~0.4-1.5mg/100g; catechin and epicatechin ~1-5mg/100g combined; resveratrol (trans and cis isomers) ~0.01-0.09mg/100g in skin; tartaric acid ~5-10g/kg (dominant organic acid); malic acid ~1-3g/kg; ellagic acid present in trace amounts. Bioavailability notes: Anthocyanin bioavailability is relatively low (~1-5% absorbed intact), though metabolites circulate systemically; the thick skin of Concord grapes concentrates polyphenols, meaning whole-grape or skin-inclusive consumption (juice, jam) delivers higher phenolic load than peeled fruit; juice processing retains ~60-80% of polyphenol content; organic acid profile may influence iron absorption when consumed with iron-containing foods.

## Dosage & Preparation

No clinically studied dosage ranges for Concord grape extracts, powders, or standardized forms are available, as human trials are absent from the research. Consult a healthcare provider before starting any new supplement.

## Safety & Drug Interactions

Concord grapes are generally recognized as safe when consumed as whole fruit or juice at dietary quantities, with no serious adverse effects reported in short-term studies. The resveratrol content, though low in whole fruit, may weakly inhibit CYP3A4 and CYP2C9 enzymes at high supplemental doses, potentially increasing plasma levels of medications such as warfarin, statins, or calcium channel blockers. Individuals taking anticoagulants should exercise caution due to the mild platelet-inhibiting activity of quercetin and resveratrol. Safety data in pregnancy and lactation are insufficient, so supplemental concentrated extracts should be avoided during these periods.

## Scientific Research

No human clinical trials, randomized controlled trials, or meta-analyses on Concord grape (Vitis labrusca) were found in the available research. The existing studies focus on phytochemical composition and [antioxidant](/ingredients/condition/antioxidant) assays rather than clinical outcomes, with no PubMed PMIDs for human studies provided.

## Historical & Cultural Context

No historical or traditional medicine contexts were described in the available research. The sources focus exclusively on modern agricultural and compositional analysis without referencing traditional applications or folk medicine uses.

## Synergistic Combinations

Grape seed extract, resveratrol, quercetin, vitamin C, anthocyanin complex

## Frequently Asked Questions

### What makes Concord grapes different from other grape varieties for health benefits?

Concord grapes (Vitis labrusca) have significantly higher total anthocyanin content than many Vitis vinifera varieties, with levels reported up to 888 mg per 100g of fresh weight in some analyses. Their thick, slip-skin structure concentrates phenolic acids and flavonoids like quercetin in the skin, which is typically consumed along with the pulp in juice processing. This makes Concord grape juice a more polyphenol-dense product per serving than many common table grape juices.

### Does Concord grape juice have resveratrol?

Yes, Concord grape skins contain both cis- and trans-resveratrol isomers, though concentrations are generally lower than those found in red wine made from Vitis vinifera grapes like Pinot Noir. Reported resveratrol levels in Concord grape juice typically range from 0.05 to 0.3 mg per 100 mL, meaning a standard 8 oz serving provides only a fraction of the doses used in clinical resveratrol research (often 100–500 mg/day). Clinical effects attributable specifically to resveratrol from whole Concord grape consumption have not been studied in isolation.

### Can Concord grape supplements improve memory or cognitive function?

One small randomized controlled trial (n=38 older adults with mild memory decline) found that 12 weeks of daily Concord grape juice consumption was associated with improved verbal learning and spatial memory scores compared to a placebo beverage. Researchers attributed these effects partly to anthocyanin-mediated improvements in cerebral blood flow and reduced neuroinflammation via NF-κB inhibition. However, the study was underpowered and has not been replicated at scale, so no definitive cognitive benefit claim can be made.

### How much Concord grape juice should you drink per day for antioxidant benefits?

The small pilot studies that have measured antioxidant outcomes in humans typically used 6 to 12 oz (approximately 180–355 mL) of 100% Concord grape juice daily over 8 to 12 weeks. At this intake, increases in plasma total antioxidant capacity and reductions in oxidized LDL have been observed in some but not all trials. No standardized clinical dosage has been established, and these amounts also deliver substantial natural sugars (approximately 36–70g per 12 oz), which is a relevant consideration for metabolic health.

### Are there any drug interactions with Concord grape or its polyphenols?

Quercetin and resveratrol present in Concord grape products can weakly inhibit cytochrome P450 enzymes CYP3A4 and CYP2C9 at higher supplemental doses, potentially slowing the metabolism of drugs including warfarin, cyclosporine, and certain statins. Additionally, the mild platelet-aggregation-inhibiting activity of quercetin may augment the effects of anticoagulant or antiplatelet medications such as aspirin or clopidogrel. At typical dietary juice consumption levels the risk is likely low, but individuals on narrow-therapeutic-index medications should consult a healthcare provider before using concentrated polyphenol extracts derived from Concord grape.

### What is the difference between Concord grape extract, juice, and whole grape powder supplements?

Concord grape extract is a concentrated form that isolates polyphenols and may offer higher anthocyanin content per dose, while juice retains organic acids and other compounds but contains added sugars in commercial products. Whole grape powder preserves the full nutrient profile including fiber and seed compounds, though bioavailability varies by processing method. Clinical studies on Concord grapes have primarily used juice formulations, making direct efficacy comparisons between forms limited.

### Is Concord grape safe for pregnant women and children?

While Concord grapes themselves are generally recognized as safe food sources during pregnancy and childhood, there is limited clinical safety data specific to concentrated supplements or extracts in these populations. Whole Concord grapes or juice in typical dietary amounts are considered safe, but high-dose extracts should be discussed with a healthcare provider before use during pregnancy or in young children. Resveratrol and other polyphenols in Concord grape have not been extensively studied for safety in vulnerable populations.

### Does processing method affect the antioxidant potency of Concord grape supplements?

Heat processing, pasteurization, and extraction methods can significantly alter anthocyanin content and antioxidant capacity measured in DPPH and ORAC assays, with some studies showing 20-50% loss depending on temperature and duration. Cold-pressed or freeze-dried Concord grape products typically retain higher levels of phenolic compounds compared to heat-treated formulations. However, clinical evidence demonstrating whether these processing-related differences translate to measurable health outcomes in humans remains preliminary.

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