Lynden, WA – Feb. 10, 2016 – Red raspberries are naturally rich in polyphenols, and as a result of research recently published in Free Radical Biology and Medicine and The Journal of Functional Foods, scientists are now beginning to understand how and why these polyphenols may offer human health benefits.

According to researcher Dr. Alan Crozier, at the Department of Nutrition, University of California, Davis, “In order to further study the potential health benefits of red raspberry consumption, it is important to first understand how the body metabolizes raspberry polyphenols, and the mode of action of the bioactive compounds that underlie these potential protective effects.”

Polyphenols are a class of phytochemicals. Polyphenols in red raspberries include: anthocyanins, flavan-3-ols, procyanidins, flavonols, ellagitannins, and hydroxycinnamates. [1-3]

Animal and cellular studies examining how phytochemicals may work at the molecular level, suggest that certain phytochemicals may help slow age-related declines which can also impact a person’s disease risk. A growing body of research is focused on how some phytochemicals may offer protection against some cancers, heart disease, stroke, high blood pressure, cataracts, osteoporosis and other chronic health conditions [4]. While current evidence is promising, additional long term studies are needed to establish the role of berry polyphenols in the prevention of specific health conditions. [5-7]. 

Assessing Bioavailability of the Active Compounds in Raspberries

Dr. Crozier and colleagues were interested in the fate of ellagitannins and anthocyanins, the compounds thought to be involved in beneficial health effects, following ingestion of the berries by human volunteers. Their study, published in Free Radical Biology and Medicine [8] looked at how these phytochemicals are metabolized by the body once ingested.

To determine this, researchers asked human volunteers to consume 300 grams of raspberries (a little over 2 cups) and then have their blood and urine samples analyzed over a 24 hour period. Analysis of these samples by high performance liquid chromatography and mass spectrometry showed an array of phytochemicals metabolites in the blood: some that peaked in the blood within 1-1.5 h, others at 6 h and still other metabolites peaking at 24 h after raspberry consumption. The work of Crozier and colleagues illustrate the complex metabolism of raspberry phytochemicals and that they are absorbed in the small intestine and the colon, which play an important role in the bioavailability of both anthocyanins and ellagitannins.

“The information discovered in our research is of importance as it enables other investigators to test these metabolites in cell-based model systems relating to cardiovascular function, colonic health and various cancers, in order to determine the mode of action of the bioactive compounds. This is critical to understanding the potential effects of raspberry consumption,” says Dr. Crozier, lead author of the study.

Reducing Inflammatory Response

A second study [9] published in the May 2015 Journal of Functional Food looked at how the metabolites of ellagitannins, called urolithins, were able to reduce the inflammatory response in rat heart muscle cells exposed to high glucose concentrations – a model which mimics a condition common in people with diabetes mellitus and hyperglycemia (high blood sugar). Overtime, this inflammation produces oxidative stress and may play a role in the development of diabetic cardiomyopathy, which can lead to heart failure. The results of this research suggest that ellagitannin-rich foods such as red raspberries, pomegranates, blackberries, strawberries and walnuts may support heart cell function. However, additional research is needed in order to determine if these compounds would have the same effect in humans.

“While this study shows the potential of ellagitannins/urolithins’ ability to help maintain normal function in the diabetic heart, further human studies are needed,” said Dr. Danielle Del Rio at the Department of Food Science, University of Parma, Italy. “In particular, the influence of a mix of circulating metabolites on the inflammatory scenario should be taken into account, and specifically designed intervention studies aimed at assessing the impact of ellagitannin-rich food sources on markers for inflammation should be performed.”

Further studies looking at the effects of red raspberries on reducing risk for conditions such as diabetes, cardiovascular disease, and other chronic diseases are currently in progress through grants funded by the National Processed Raspberry Council.

About the National Processed Raspberry Council

Created in 2013, the National Processed Raspberry Council (NPRC) represents the processed raspberry industry and is supported by assessments from both domestic producers and importers. NPRC’s mission is to conduct nutrition research and promote the health benefits of processed raspberries. The NPRC is responsible for marketing processed raspberries in the U.S. and is committed to promoting the growth of the entire industry. Processed raspberries are frozen at the peak of ripeness to lock in flavor and nutrition. Visit for more information, and follow us on our social media channels: on ,,; or

  1. SH, Park SW. Edible berries: Bioactive compounds and their effects on human health. Nutrition 2014, 30, 134-
  2. Mullen W, Lean ME, Crozier A. Rapid characterization of anthocyanins in red raspberry fruit by high-performance liquid chromatography coupled to single quadrupole mass spectrometry. J Chromatography A 2002, 9, 966, 63-
  3. Mullen W, Yokota T, Lean MEJ, Crozier A. Analysis of ellagitannins and conjugates of ellagic acid and quercetin in raspberry fruits by LC-MSn. Phytochemistry 2003, 64, 617-
  4. Academy of Nutrition and Dietetics Complete Food and Nutrition Guide. John Wiley & Sons Inc. 2012, pp. 153-
  5. Rodriguez-Mateos AM, Heiss C, Borges G, Crozier A. Berry polyphenols and cardiovascular health. Journal of Agricultural and Food Chemistry 2014, 62, 3842-
  6. Basu A, Rhone M, Lyons TJ. Berries emerging impact on cardiovascular health. Nutrition Review 2010, 68, 168-
  7. Alyer HS, Kichambare S, Gupta RC. Prevention of oxidative DNA damage by bioactive berry components Nutrition and Cancer 2008, 60(S1), 36-
  8. Ludwig IA, Mena P, Calani L, Borges G, Pereira-Caro G, Bresciani L, Del Rio D, Lean MEJ, Crozier A. New insights into the bioavailability of red raspberry anthocyanins and ellagitannins. Free Radical Biology and Medicine 2015, 89, 758–769
  9. Sala R, Mena P, Savi M, Brighenti F, Crozier A, Miragoli M, Stilli D, Del Rio, D. et al. Urolithins at physiological concentrations affect the levels of pro-inflammatory cytokines and growth factor in cultured cardiac cells in hyperglucidic conditions. Journal of Functional Foods 2015, 15, 97–105.


handful of raspberries


LYNDEN, WA, Feb. 10 2016 – Components in red raspberries may have anti-inflammatory, anti-oxidative and metabolic stabilizing activity, according to a comprehensive review of the available scientific literature published in the January issue of Advances in Nutrition. These properties shed light on the potential role of red raspberries in helping to reduce the risk of metabolically-based chronic diseases, including cardiovascular disease, diabetes mellitus, obesity, and Alzheimer’s disease: all of which share critical metabolic, oxidative, inflammatory links.

Red raspberries contribute a number of valuable essential nutrients, including providing an excellent source of vitamin C and nine grams of fiber per cup. They are also among the few plant foods that provide a source of ellagitannins and anthocyanins in the same package. The evidence is suggesting that the action of these nutrients and phytochemicals in the body hold the key to red raspberry’s health promoting properties.

“Turns out what is good for the heart, is also good for the brain. That is what is particularly interesting about the research on red raspberries – their potential to help reduce factors contributing to metabolic syndrome which has implications for diabetes development and overall cardiovascular and brain health,” says Britt M. Burton-Freeman, PhD, MS of the Center for Nutrition Research, Institute for Food Safety and Health, Illinois Institute of Technology, and lead author of the paper.

Heart Disease

Heart disease remains the leading cause of death, accounting for 17.5 million deaths a year globally.   While lifestyle factors (healthy diet, exercise, not smoking) have been well researched in reducing the risk of cardiovascular disease, emerging research shows a major underlying cause is cellular/tissue dysfunction and damage caused by excess oxidative stress and inflammation. Animal and cellular studies have shown that after red raspberry exposure or feeding, ellagic acid, the primary breakdown product of ellagitannins, can reduce oxidative stress and inflammation. While these studies show the potential to help decrease atherosclerosis development, increase vasodilation and lower blood pressure, the next step is to verify and validate this effect in humans.


Recent statistics indicate that approximately 29.1 million people or 9.3% of the U.S. population has diabetes. Insulin resistance has been recognized as a major risk factor for developing diabetes and precipitates many of the risk factors of cardiovascular disease.

In the review of the scientific literature, limited studies suggests that different polyphenolic components of red raspberries have biological activity that could be clinically relevant in reducing disease risk and or management of diabetes, including helping to improve insulin responses and reducing blood glucose levels.

Additional research is needed in at risk individuals to better understand the role of red raspberries in reducing diabetes disease risk.


Overweight and obesity are major risk factors for type-II diabetes, cardiovascular disease, and some cancers. In the U.S., more than two-thirds of adults are overweight or obese.

Research conducted in mice fed a high fat diet found that the addition of raspberry ketones decreased body weight and increased the breakdown of fat. This study was popularized in the media, but the effects of raspberry ketones have not been adequately tested in human studies, primarily because it is difficult to replicate the concentrations of raspberry ketones (2% of diet) used in the animal studies.

Raspberries have the highest fiber content compared to other berries (9 grams per cup). Dietary fiber is associated with satiety and helping to reduce food intake, which can assist with weight control.

Alzheimer’s Disease

Metabolic syndrome refers to a cluster of cardio-metabolic risk factors including abdominal obesity, high blood pressure, impaired glucose and insulin metabolism, as well as elevated triglycerides and low concentrations of high density lipoprotein (HDL) cholesterol. In addition to increasing the risk for heart disease and diabetes, the metabolic syndrome has also been linked with cognitive impairment, dementia and development of Alzheimer’s.

Studies on the role of red raspberries with respect to Alzheimer’s disease are very limited, although the association between red raspberry or its polyphenol components in reducing oxidative stress, inflammation, and improving insulin signaling can be considered promising for Alzheimer’s disease risk reduction as well slowing the aging process. Dr. Burton-Freeman suggests that the available data supports further research on the role of red raspberries in preserving brain health.

About the National Processed Raspberry Council

Created in 2013, the National Processed Raspberry Council (NPRC) represents the processed raspberry industry and is supported by assessments from both domestic producers and importers. NPRC’s mission is to conduct nutrition research and promote the health benefits of processed raspberries. The NPRC is responsible for marketing processed raspberries in the U.S. and is committed to promoting the growth of the entire industry. Processed raspberries are frozen at the peak of ripeness to lock in flavor and nutrition. Visit for more information, and follow us on our social media channels: on ,,; or

In the Spotlight: Articles Featuring Frozen Raspberries



Attendees at last summer’s harvest tour continue to educate their readers about the value of frozen raspberries:


Raspberry Chipotle Chicken with Lime + A Raspberry Farm Tour

Teaspoon of Spice Blog, by Serena Ball

This article includes a recap of the Raspberry Harvest Tour, and recognition of the culinary versatility of raspberries to pair well with other strong flavors like chipotle pepper and bright lime.


Should You Reach for Frozen Fruit When Fresh Isn’t in Season?

Food Network’s Healthy Eats Blog, by Cameron Curtis

This article highlights the benefits of frozen berries and includes raspberry nutrition information and recipes that incorporate frozen raspberries.


And there’s more!

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Researchers Paint Bright Future for Berry Research, Interview with Dr. Britt Burton-Freeman



The NPRC recently attended the Berry Health Benefits Symposium (BHBS) in Madison, WI where nearly 150 researchers and industry members gathered to hear the latest research from scientists from both the U.S. and abroad.

We caught up with Britt Burton-Freeman, Ph.D. the Director of the Center for Nutrition Research at the Institute for Food Safety and Health and Associate Professor, Food Science and Nutrition at the Illinois Institute of Technology to hear first-hand about her key takeaways from the Berry Health Benefits Symposium and the NPRC’s Raspberry Roundtable. Dr. Burton-Freeman is the Science Advisor for the NPRC where she helps guide health research strategy and provides ongoing counsel regarding the interface between research and marketing.

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