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Concord Grapes and Health

Concord Grapes and Health

Power of the Concord Grape

For years leading researchers have been investigating the nutrition power of Concord grapes. Growing evidence now suggests that eating and drinking Concord grapes and Concord grape products, as part of a produce-rich diet and active lifestyle, may positively impact health. Concord grape research has focused mainly on the fruit’s role in cardiovascular or heart health, but other emerging areas are also being studied. Discover more on the state of this research below:

Cardiovascular (Heart) Health

As part of a nutritious diet and active lifestyle, Concord grapes may be one important ingredient for maintaining a healthy cardiovascular system. More than a decade’s worth of science indicates that Concord grape juice may help support flexible arteries to promote healthy blood flow. And while additional research is necessary to draw any conclusions, early findings suggest that Concord grapes have the potential to play a role in helping certain groups of people maintain healthy blood pressure. Find out what has been uncovered.
Learn more about grapes and cardiovascular health

Cognitive (Mind) Health

Researchers have begun investigating the role of Concord grapes in cognitive health. The research in this area is very preliminary, yet emerging science suggests that Concord grapes may offer certain cognitive health benefits. Recent studies indicate that Concord grape juice may help slow the progression of age-related cognitive decline. More research is needed before any conclusions can be drawn, but find out what has been uncovered.
Learn more about grapes and cognitive health

Immune System Health

Very preliminary science suggests that the immune system may be supported by the plant nutrients (phytonutrients) and micronutrients found within Concord grapes. More research is needed before any conclusions can be drawn, but find out what has been uncovered.
Learn more about grapes and immune system health

Additional Reading

A comprehensive literature review published in the November 2010 issue of Nutrition Reviews provides a summary of the well-established and emerging areas of research on the role of grapes and grape products (including Concord grape juice) in promoting health. Learn more

Concord Grapes and Nutritious Diets

Most people fall short on getting enough fruit in their diet every day, and Concord grapes and Concord grape juice can help people easily squeeze more vibrantly colored fruit into a healthy daily diet.

For example:

  • Most people don’t meet the daily recommendations for fruit, and the 2010 Dietary Guidelines for Americans recommends that everyone – adults and children – get more fruit each day.1 About 16 grapes (one handful) equals 1/2 cup or one serving of fruit.2 And remember, all forms of fruit count towards daily requirements.1 As a complement to whole fruit, 100% juice can be a convenient and widely accessible way to boost fruit intake.

Research has found that drinking 100% juice made with Concord grapes in moderation can be part of a balanced diet while maintaining a healthy weight.

Specifically, while more research is necessary, early studies have shown that daily, moderate consumption of grape juice does not significantly impact weight.3-6

  • One study of healthy, overweight men and women ages 18-50 years found that, after 12 weeks, Concord grape juice drinkers consuming about 2 cups per day had no significant changes in appetite or weight, and showed a significant decrease in waist circumference (one of the five determinants of metabolic syndrome). Other markers of metabolic syndrome, including cholesterol, triglyceride, and fasting glucose levels, were maintained within normal limits throughout the study. The group that drank a sugar-sweetened beverage in place of the Concord grape juice felt less full, experienced moderate weight gain, and did not experience a significant decrease in waist circumference.5 A recent pilot study also found that daily Concord grape juice consumption had no negative impact on body weight or waist circumference.3
  • According to a recent analysis using the National Health and Nutrition Examination Survey (NHANES), children and adults who consumed 100% grape juice showed no significant differences in weight or BMI compared to non-drinkers.7 These findings support other observational studies, which discovered that children and teens who drank 100% juice tended to consume more nutritious diets and were no more likely to be overweight than non-juice drinkers.8-10


  1. U.S. Department of Agriculture and U.S. Department of Health and Human Services. Dietary Guidelines for Americans, 2010. 7th Edition, Washington, DC. US Government Printing Office, December 2010. (Accessed April 8, 2011).
  2. U.S. Department of Agriculture. Website. Washington, DC. Food Groups: Fruit. Last Updated: June 21, 2011. (Accessed: July 15, 2011).
  3. Krikorian R, Nash TA, Shidler MD, Shukitt-Hale B and Joseph JA. Concord grape juice supplementation improves memory function in older adults with mild cognitive impairment. Br J Nutr. 2010. 103(5):730-734.
  4. Park YK, Kim JS and Kang MH. Concord grape juice supplementation reduces blood pressure in Korean hypertensive men: double-blind, placebo controlled intervention trial. Biofactors. 2004. 22(1-4):145-147.
  5. Hollis JH, Houchins JA, Blumberg JB and Mattes RD. Effects of concord grape juice on appetite, diet, body weight, lipid profile, and antioxidant status of adults. J Am Coll Nutr. 2009. 28(5):574-582.
  6. Dohadwala MM, Hamburg NM, Holbrook M, Kim BH, Duess M-A, Levit A and Titas M. Effects of Concord grape juice on ambulatory blood pressure in prehypertension and stage 1 hypertension. Am J Clin Nutr, Am J Clin Nutr. 2010. 92(5):1052-1059.
  7. McGill CR, Wightman JD, Fulgoni S and Fulgoni III VL. Consumption of Purple/Blue Produce is Associated with Increased Nutrient Intake and Reduced Risk for Metabolic Syndrome: Results From the National Health and Nutrition Examination Survey 1999-2002. Am J Lifestyle Med. 2011. 5(3):279-290.
  8. Nicklas TA, O'Neil CE, Kleinman R. Association between 100% juice consumption and nutrient intake and weight of children aged 2 to 11 years. Arch Pediatr Adolesc Med. 2008.162(6):557-565.
  9. O'Connor TM, Yang SJ, Nicklas TA. Beverage intake among preschool children and its effect on weight status. Pediatrics. Oct 2006;118(4):e1010-1018.
  10. O'Neil CE, Nicklas TA and Kleinman R. Relationship between 100% juice consumption and nutrient intake and weight of adolescents. Am J Health Promot. 2010. 24(4):231-237.
Eating a balanced diet rich in a variety of fruits and vegetables is important for maintaining overall health. Delicious Concord grapes and 100% grape juice are part of a nutritious diet, but they should not be used to treat health problems. If you are worried about your health or are faced with a medical concern, be sure to consult with your doctor.

Guide to Navigating Research Studies

The definition of scientific research is performing a methodical study in order to prove a theory or answer a question. The following is a brief overview of different types of research used in health and nutrition exploration 1:

Case-Control Study
Clinical Study
Cohort Study
Cross-Sectional Study
Observational Study
Pilot Study
Preclinical or Laboratory Studies
Randomized Controlled Trials


1. Hulley SB, Cummings SR, Browner WS, Grady D, Hearst N, Newman TB. Designing Clinical Research: An Epidemiologic Approach. 3rd ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2007.

Grape Research Overview

For nearly 20 years, researchers have been exploring an important mix of plant nutrients – polyphenols – found in Concord grapes and the effects they have on the body, including possible benefits in supporting cardiovascular health. In addition, emerging research is being conducted to determine whether Concord grapes play a role in supporting a healthy mind and immune system. See the research.


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An observational study, usually a retrospective study (a study that looks backward in time) that compares two groups of people: 1) those with the specific condition (e.g., disease) being studied (cases) and, 2) a similar group of people without that condition (controls). Researchers compare these two groups of people and important characteristics, such as certain lifestyle choices, to determine what factors may be associated with the condition under investigation.

A type of study that often includes patients with specific health conditions who could benefit from receiving a new treatment. These studies can also be performed in healthy subjects. The end goal of a clinical study (also called clinical research or clinical trial) is to determine effectiveness and safety of a health intervention in humans.

An observational study, usually prospective (looking forward), that follows a group of similar people over time. The goal is to determine which factors and exposures affect the development of a specific outcome or health condition (e.g., disease) during the study’s time period.

A type of observational study, often given as a survey, that examines a group of subjects during a single occasion, or over a very short period of time. This type of study aims to describe the relationship between health-related conditions (e.g., metabolic syndrome, hypertension) and other factors that exist in the general population (e.g., dietary intake, physical activity levels), during a particular time period.

A type of study in which researchers simply observe subjects and measure the associations between certain characteristics (e.g., fruit/vegetable intake) and specific outcomes (e.g., obesity). Examples of observational studies include case-control studies, cross-sectional studies, and cohort studies. While these studies gather important information, they cannot prove that a specific treatment or factor affects health.

A small scale, preliminary study that is conducted to determine the potential for a larger study.

A stage of research that often occurs prior to trials involving humans. This type of research can help determine mechanisms of action of a treatment, or how the treatment is causing the effect, as well as help ensure the safety of treatment in subsequent human trials.

In vitro
Testing performed in a controlled environment, such as a test tube or a Petri dish, instead of living organisms. In vitro literally means "within the glass" in Latin.

Ex vivo
These experiments are performed on tissue (e.g., animal or human cells) taking place outside of the organism, such as in a laboratory setting. In Latin, this means "out of the living."

In vivo
These tests are done on whole, living organisms. Technically, animal and human testing are two forms of in vivo research, which means "within the living." These experiments may be performed outside of a laboratory setting.

A study designed to provide the most credible information about the cause and effects of treatment. These types of studies are recognized as unbiased because they involve the random assignment of treatments to subjects being studied.

The tendency throughout any stage of research to generate findings that may not reflect "true values." In clinical trials, researchers try to avoid many kinds of bias, including selection by randomizing subjects, measurement by creating placebos and performing blind trials, and confounding by carefully designing the study and analyzing the findings.

Study in which subjects do not know whether they receive the treatment or the placebo, which assists in prevention of bias. Double-blinded studies are a higher level of scientific rigor because neither the participants nor the investigators know who is receiving the treatment or the placebo. A double-blind crossover study means each participant undergoes both the treatment and control scenario, typically with a wash-out period in between.

Study that allows researchers to isolate the effect size of the treatment by comparing a group given a simulated treatment (e.g., grape flavored drink) to those with the real treatment (e.g., Concord grape juice), which reduces measurement bias. The placebo should match as closely as possible to the treatment without containing the active ingredients.

Study involving participants who are randomly assigned to either the treatment or the placebo group, reducing selection bias.