For many years, researchers believed that the ability of cranberries and cranberry juice to help prevent urinary tract infections (UTIs) was partly related to the strong acidity of the cranberries. Recent research has shown that it's not the acidity of the cranberries, but the unusual nature of their proanthocyanidins (PACs) that is related to prevention of UTIs. The special structure of these PACs (involving A-type linkages between their components) acts as a barrier to bacteria that might otherwise latch on to the urinary tract lining. In many studies, the UTI-preventing benefits of cranberries are somewhat modest and limited to women who have recurrent UTIs. But this whole area of investigation has opened the door to an understanding of other possible cranberry benefits. For example, stomach ulcers are often related to overgrowth and over-linking of one particular type of stomach bacteria (Helicobacter pylori) to the stomach lining. In much the same way as cranberries may help prevent bacterial attachment to the lining of the urinary tract, they may also help prevent attachment of bacteria to the stomach lining. There is already some preliminary evidence that cranberry may help protect us from stomach ulcer in this way. We expect to see future studies confirming this fascinating type of health benefit.
Many cranberries are water-harvested. Water-harvesting means that the cranberries are grown in bogs and floated in water to allow for easy harvesting. For many years, water-harvesting of cranberries has been looked upon as an industry convenience. It's simply easier to harvest berries that are floating on the surface. However, recent research has shown that the anthocyanin content of cranberries (the phytonutrients that give the berries their amazing red color) is increased in direct proportion to the amount of natural sunlight striking the berry. If berries floating on top of water get exposed to increased amounts of natural sunlight (in comparison to other growing and harvesting conditions), they are likely to develop greater concentrations of anthocyanins. These greater concentrations of anthocyanins are likely to provide us with stronger health benefits. In other words, water-harvesting may turn out to provide more than just harvest convenience. If it can expose cranberries to greater amounts of natural sunlight, it can increase phytonutrient health benefits that involve the unique antioxidant and anti-inflammatory properties of anthocyanins.
A substantial number of recent studies have shown that whole cranberries consumed in dietary form—in comparison with purified cranberry extracts consumed in either liquid or dried supplement form—do a better job of protecting our cardiovascular system and our liver. Several groups of researchers have summarized their health benefit findings by pointing out that it is the synergy among cranberry nutrients (rather than individual cranberry components) that is responsible for cranberry's health benefits. This synergy is only found in the whole berry as consumed in food form. This rule about whole dietary intake appears to apply to the antioxidant benefits, anti-inflammatory benefits, and anti-cancer benefits of cranberry.
Over the past 5 years, scientists have identified an increasing number of mechanisms that help explain the anti-cancer properties of cranberries. These mechanisms are now known to include: blocked expression of MMPs (matrix metalloproteinases); inhibition of ODC (ornithine decarboxylase enzymes); stimulation of QRs (quinone reductase enzymes); inhibition of CYP2C9s (Phase I detoxification enzymes); and triggering of apoptosis (programmed cell death) in tumor cells. The cancer-preventive benefits of cranberries are now known to extend to cancers of the breast, colon, lung, and prostate.
Foods Recommendations In our Healthiest Way of Eating Plan, we encourage the consumption of 5-10 servings of fruits-plus-vegetables (combined) eat day. We believe that the balance between fruits and vegetables can vary from day to day, depending upon personal health factors, personal taste preferences, and optimal combining of foods in recipes as well as meals. We recognize that our recommendation calls for a more generous amount of fruits and vegetables than the amount recommended by the Centers for Disease Control (CDC) at the U.S. Department of Health and Human Services (DHHS). The CDC recommends between 1.5-2.5 cups of fruit and 2.5-4.0 cups of vegetables per day, as well as a target goal of at least 5 fruit-plus-vegetable servings (combined) per day. With respect to berries, the CDC approach provides the example of strawberries, and explains that 8 large strawberries count as 1 cup. If all fruit for the day were to be obtained from strawberries, the CDC recommendation would translate into 12-20 strawberries for the day as a way of meeting a requirement for 1.5-2.5 cups of fruit. We recommend that you set your fruit goals higher than these CDC amounts. Based on the scientific research, we believe it's going to take closer to 3 fruit servings per day to provide you with optimum health benefits. With respect to berries in particular, we recommend that you include berries at least 3-4 times per week within your fruit servings. In several of our sample meal plans, we include berries on a daily basis! It would definitely not be a mistake for you to include a serving of berries in your daily meal plan! At the same time, we recognize that the fruit group contains many outstanding fruit options, and personal preferences (as well as local and seasonal availability) can vary greatly. Also, remember that large strawberries—at about 18 grams per berry and 8 berries per cup—stand at one end of the berry range in terms of size and recommended amount. Most berries are considerably smaller in size and weight, and a one-cup serving allows you to eat a lot more berries! With blueberries, for example, the average weight per berry is closer to 1-2 grams, and a cup's worth of blueberries means about 100-150 berries. For cranberries and raspberries, the amount would be similar. Among the fruits and vegetables richest in health-promoting antioxidants berries such as cranberries rank right up there at the top of the list. Antioxidants are essential to optimizing health by helping to combat the free radicals that can damage cellular structures as well as DNA. Provided that you do not experience any digestive difficulty, we recommend enjoying cranberries raw because they provide you with the best flavor and the greatest benefits from their vast array of nutrients, and may also offer the benefit of digestion-aiding enzymes. When you think about the flavors, nutrients, and enzyme content of raw fruit, it is no surprise that for thousands of years both in Asia and along the Mediterranean, people have been eating raw fruit for dessert, not only as a delicious and nutritious ending to a meal but also as a potential digestive aid. For more on the Healthiest Way of Preparing Cranberries, see the How to Enjoy section below.
Protection against Urinary Tract Infection (UTI) Long before researchers started investigating from the standpoint of science, cranberry has been used to help prevent and treat urinary tract infections (UTIs). While the acidity of cranberries was at one time an important target of research, we now know that cranberry's ability to provide UTI benefits is not primarily related to its acidity, but rather to its proanthocyanidin (PAC) content. The PACs in cranberry have a special structure (called A-type linkages) that makes it more difficult for certain types of bacteria to latch on to our urinary tract linings. Include in these types of bacteria are pathogenic (infection-causing) strains of E. coli—one of the most common microorganisms involved in UTIs. By making it more difficult for unwanted bacteria like E. coli to cling onto the urinary tract linings, cranberry's PACs help prevent the expansion of bacterial populations that can result in outright infection. The age group in which researchers are least sure about this process involves children—it's just not clear when cranberry's health benefits fully extend to this age group. The area where benefits have been most pronounced are in middle-aged women who have experienced recurrent UTIs. In some studies, UTIs in this age and gender group have been reduced by more than one—third through dietary consumption of cranberry. The discovery that cranberries prevent UTIs by blocking adhesion of bacteria to the urinary tract lining is a discovery that has allowed research on cranberry to expand out in other important directions. In our Digestive Benefits section below, we will describe how prevention of stomach ulcer is one very intriguing new direction in the cranberry research, based on this exact same principle of blocking bacterial adhesion to the lining of an organ system. (In the case of stomach ulcer, it's the stomach lining that's at risk, and the bacteria involved are theHelicobacter pylori bacteria.) Anti-Inflammatory BenefitsFor the cardiovascular system and for many parts of the digestive tract (including the mouth and gums, stomach, and colon) cranberry has been shown to provide important anti-inflammatory benefits. It's the phytonutrients in cranberry that are especially effective in lowering our risk of unwanted inflammation, and virtually all of the phytonutrient categories represented in cranberry are now known to play a role. These phytonutrient categories include proanthocyanidins (PACs), anthocyanins (the flavonoid pigments that give cranberries their amazing shades of red), flavonols like quercetin, and phenolic acid (like hydroxycinnamic acids).
In the case of our gums, the anti-inflammatory properties of cranberry can help us lower our risk of periodontal disease. Chronic, excessive levels of inflammation around our gums can damage the tissues that support our teeth. It's exactly this kind of inflammation that gets triggered by ongoing overproduction of certain cytokines. (Cytokines are messaging molecules, and the pro-inflammatory cytokines tell our cells to mount an inflammatory response. As messages are sent more frequently and more constantly, the inflammatory response becomes greater.) Phytonutrients in cranberry help reduce this inflammatory cascade of events precisely at the cytokine level. Production of pro-inflammatory cytokines like interleukin 6 (IL-6) and RANTES (Regulated Activation Normal T-cell Expressed and Secreted) is lowered by the activity of cranberry phytonutrients. In addition, cranberry phytonutrients inhibit the activity of the enzymes cyclo-oxygenase 1 (COX-1) and cyclo-oxygenase 2 (COX-2). These COX-1 and COX-2 enzymes are key factors in the production of other pro-inflammatory messaging molecules, and by inhibiting these enzymes, cranberry's phytonutrients significantly lower our risk of unwanted inflammation. Dietary consumption of cranberry has also been shown to reduce the risk of chronic, unwanted inflammation in the stomach, large intestine (colon) and cardiovascular system (especially blood vessel linings). We'll discuss some of these health benefits in more detail in the Digestive Benefits and Cardiovascular Benefits sections of this cranberry profile. Immune SupportWhile research in this area is somewhat limited, recent studies on the immune support benefits of cranberry are exciting. In studies on very small numbers of human participants, intake of cranberry extracts has shown the ability to improve multiple aspects of immune function, and to lower the frequency of cold and flu symptoms in the subjects. In several of these studies, the cranberry extracts were standardized to contain a known, higher-end amount of proanthocyanidins (PACs)—somewhat comparable to a double-strength cranberry juice. From our perspective, the doses of cranberry extract used in these studies match up fairly well with generous intake of whole, raw cranberries, and we look forward to future studies focused on precisely that: intake of whole, raw cranberries and resulting changes in cold and flu symptoms.
Cardiovascular Benefits Following decreased risk of urinary tract infection (UTI), increased health of the cardiovascular system is perhaps the best-researched area of cranberry health benefits. It's the combined impact of cranberry antioxidants and anti-inflammatory phytonutrients in cranberry that's responsible here. Oxidative stress and chronic inflammation can place our blood vessel walls at great risk of damage. Once damaged, our blood vessels walls can undergo a process of plaque formation, and our risk of atherosclerosis (blood vessel wall thickening and blood vessel blocking) can be greatly increased. Dietary intake of cranberries and cranberry juice (in normal everyday amounts, unchanged for research study purposes) has been shown to prevent the triggering of two enyzmes that are pivotal in the atherosclerosis process (inducible nitric oxide synthase, or iNOS, and cyclo-oxygenase 2, or COX-2). In both cases, cranberry has also been shown to prevent activation of these enzymes by blocking activity of a pro-inflammatory cytokine-messaging molecule called tumor necrosis factor alpha (TNF-alpha). These anti-inflammatory benefits of cranberry appear to be critical components in the cardiovascular protection offered by this amazing fruit. The antioxidant components of cranberries also appear to play a key role in cranberry's cardiovascular benefits. In animal studies, these antioxidant benefits have been clearly associated with decreased risk of high blood pressure. By reducing oxidative stress inside the blood vessels, cranberry extracts consumed by rats and mice have helped prevent overconstriction of the blood vessels and unwanted increases in blood pressure. Three related phytonutrient compounds—resveratrol, piceatannol, and pterostilbene—deserve special mention with respect to cranberry's antioxidants. These unique phytonutrients may provide cranberry with some equally unique antioxidant properties, and a special ability to support our cardiovascular system in this regard. A final area of cardiovascular support provided by cranberry is its ability to help us lower our LDL-cholesterol and total cholesterol, while simultaneously helping us increase our level of HDL-cholesterol. Cranberry most likely helps us achieve these cholesterol-improving changes by helping to improve oxidative and inflammatory aspects of the everyday environment in which our cholesterol-containing molecules must exist. This improved cholesterol control offered by cranberry contributes even further to our decreased risk of blood vessel blocking problems, since excess accumulation of LDL-cholesterol and insufficient amounts of HDL-cholesterol can increase the tendency of our blood vessels to become blocked. All in all, it's quite amazing how a simple food like cranberry can provide us with cardiovascular benefits at so many different levels, all rolled into one.
Antioxidant Protection Although previously mentioned in this Health Benefits section, the antioxidants found in cranberry are especially important contributors to its potential for health support. From a research perspective, there are two especially important points to consider when thinking about the antioxidant benefits of cranberries. First is the amazing array of antioxidants that are found exclusively in whole cranberries. Cranberry's special combination of phenolic antioxidants, proanthocyanidin antioxidants, anthocyanin antioxidants, flavonoid antioxidants, and triterpenoid antioxidants is without a doubt unique. Also unique is the particular combination of three antioxidant nutrients—resveratrol, piceatannol, and pterostilbene—found in cranberry. Second are the research findings regarding the synergy between these nutrients. The phytonutrients in cranberry provide maximal antioxidant benefits only when consumed in combination with each other, and also only when consumed alongside of conventional antioxidant nutrients present in cranberry like manganese and vitamin C. When cranberry processing disrupts this antioxidant combination, health benefits from cranberry are decreased. Multiple studies in multiple health benefit areas point to this same conclusion—it's the overall blend of cranberry antioxidants that provides us with the strongest health benefits. One further point about cranberry antioxidant research seems worthy of mention. In several research studies, cranberries were unable to provide significant antioxidant benefits when those benefits were measured in terms of blood values. In these studies, it took a much closer look at activities going on inside of our cells to demonstrate the antioxidant benefits of cranberries. The need to look inside of our cells to find cranberry antioxidant benefits may be telling us that the special value of cranberries may often involve metabolic events that are taking place "behind the scenes." In other words, these benefits may sometimes be missed in more broadly focused research studies, and cranberry may in fact have a stronger research track record than previously assumed.
Anti-Cancer Benefits No area of cranberry research has been more intriguing in the past 10 years than research on cranberry and cancer, even though the majority of studies in this area have involved lab studies on human cancer cells or animal experiments. On a virtual year-by-year basis, scientists continue to identify new mechanisms that establish cranberries as anti-cancer agents. These mechanisms are now known to include: blocked expression of MMPs (matrix metalloproteinases); inhibition of ODC (ornithine decarboxylase enzymes); stimulation of QRs (quinone reductase enzymes); inhibition of CYP2C9s (Phase I detoxification enzymes); and triggering of apoptosis (programmed cell death) in tumor cells. It's important to point out that this amazing list of anti-cancer properties in cranberry is not sufficient to establish cranberry as a food to be used in the treatment of cancer. However, it is a list that appears consistent with other studies of cranberry and cancer showing dietary intake of this food to help prevent cancer occurrence. These cancer-preventive benefits of cranberry are especially likely in the case of breast, colon, lung, and prostate cancer. None of the cancer-related benefits of cranberries should be surprising, since cranberry is loaded with antioxidant and anti-inflammatory nutrients. Chronic excessive oxidative stress (from lack of sufficient antioxidant support) and chronic excessive inflammation (from lack of sufficient anti-inflammatory compounds) are two key risk factors promoting increased likelihood of cancer. With its unique array of antioxidant and anti-inflammatory nutrients, cranberry seems ideally positioned to help us lower our risk of cancer development. Digestive Tract Benefits When you add up the health-related benefits of cranberry for our mouth and gums (decreased risk of periodontal disease), stomach (decreased risk of stomach ulcer), and colon (decreased risk of colon cancer), it's impossible not to conclude that cranberry is unique among fruits in its ability to provide us with digestive tract benefits. Every category of phytonutrient known to be provided by cranberry is also known to play a role in digestive tract support. In the case of cranberry's proanthocyanidins, it's decreased adherence of the bacterium Helicobacter pylori to our stomach wall that's made possible by intake of cranberry. In the case of cranberry's flavonoids, anthocyanins and triterpenoids, provide antioxidant and anti-inflammatory benefits that decrease our risk of colon cancer, and also our risk of periodontal disease.
Recent research has also shown that cranberry may be able to help optimize the balance of bacteria in our digestive tract. Participants in one recent study involving cranberry juice intake (in amounts of approximately 2 ounces per day and over the course of about 3 months) were able to increase the numbers of Bifidobacteria in their digestive tract while maintaining other bacterial types (Bifidobacteria are typically considered to be a desirable and "friendly" type of bacteria). As a result, the relative amount of Bifidobacteria was increased, and the bacterial environment of the digestive tract may have become more favorable. Given the vast array of phytonutrients in cranberry and the known connection between so many of these phytonutrients and digestive tract health, we expect to see the digestive benefits of cranberry becoming more and more apparent in future research on this incredible berry. Description A glossy, scarlet red, very tart berry, the cranberry belongs to the same genus as the blueberry, Vaccinium. (Both berries also belong to the food family called Ericaceae, also known as the heath or heather family.) Like blueberries, cranberries can still be found growing as wild shrubs in northern Europe, northern Asia, and North America. When cultivated, however, cranberries are grown on low trailing vines atop great sandy bogs. Cranberries have also been called "bounceberries," because ripe ones bounce, and "craneberries," a poetic allusion to the fact that their pale pink blossoms look a bit like the heads of the cranes that frequent cranberry bogs. The variety cultivated commercially in the northern United States and southern Canada, the American cranberry, produces a larger berry than either the Southern cranberry, a wild species that is native to the mountains of the eastern United States, or the European variety. Cranberries have long been valued for their ability to help prevent and treat urinary tract infections. Now, recent studies suggest that this native American berry may also promote gastrointestinal and oral health, lower LDL and raise HDL (good) cholesterol, aid in recovery from stroke, and even help prevent cancer. Fresh cranberries, which contain the highest levels of beneficial nutrients, are at their peak from October through December, just in time to add their festive hue, tart tangy flavor and numerous health protective effects to your holiday meals. When cranberries' short fresh season is past, rely on unsweetened cranberry juice made from whole berries and dried or frozen cranberries to help make every day throughout the year a holiday from disease.
History American Indians enjoyed cranberries cooked and sweetened with honey or maple syrup—a cranberry sauce recipe that was likely a treat at early New England Thanksgiving feasts. By the beginning of the 18th century, the tart red berries were already being exported to England by the colonists. Cranberries were also used by the Indians decoratively, as a source of red dye, and medicinally, as a poultice for wounds since not only do their astringent tannins contract tissues and help stop bleeding, but we now also know that compounds in cranberries have antibiotic effects. Although several species of cranberries grow wild in Europe and Asia and have always been enjoyed in these part of the world, the cranberry most cultivated as a commercial crop is an American native, which owes its success to one Henry Hall, an observant gentleman in Dennis, Massachusetts. In 1840, Mr. Hall noticed an abundance of large berries grew when sand was swept into his bog by the prevailing winds and tides. The sandy bog provided just the right growing conditions for the cranberries by stifling the growth of shallow-rooted weeds, thus enhancing that of the deep rooted cranberries. Cranberry cultivation soon spread not only across the U.S. through Wisconsin to Washington and Oregon, but also across the sea to Scandinavia and Great Britain. The hardy berries arrived in Holland as survivors of a shipwreck. When an American ship loaded with crates filled with cranberries sank along the Dutch coast, many crates washed ashore on the small island of Terschelling; some of the berries took root, and cranberries have been cultivated there ever since. In terms of scientific classifications, one of the most common cranberry types is Vaccinium oxycoccos, sometimes referred to as European cranberry. This species of cranberry is native to the Northern Hemisphere and found not only in Northern Europe but also Northern Asia and Northern North America. Another common type--Vaccinium macrocarpon—is larger and more common along the eastern parts of the United States and Canada. This is the cranberry species that is most widely commercially cultivated. Vaccinium microcarpum is a smaller cranberry species that is most widely found in Northern Europe and Northern Asia.
How to Select and Store A fruit with a short season, fresh cranberries are harvested between Labor Day and Halloween and appear in markets from October through December. Choose fresh, plump cranberries, deep red in color, and quite firm to the touch. Firmness is a primary indicator of quality. In fact, during harvesting, high quality cranberries are often sorted from lesser quality fruits by bouncing the berries against barriers made of slanted boards. The best berries bounce over the barriers, while the inferior ones collect in the reject pile. The deeper red their color, the more highly concentrated are cranberries' beneficial anthocyanin compounds. The Early Black cultivar (variety) of cranberry—with its particularly deep red color—has been found in one research study to have the highest concentration of anthocyanins. Although typically packed in 12-ounce plastic bags, fresh cranberries, especially if organic, may be available in pint containers. Fresh ripe cranberries can be stored in the refrigerator for up to 20 days. Before storing, discard any soft, discolored, pitted or shriveled fruits. When removed from the refrigerator, cranberries may look damp, but such moistness does not indicate spoilage, unless the berries are discolored or feel sticky, leathery or tough. Once frozen, cranberries may be kept for several years. To freeze, spread fresh cranberries out on a cookie sheet and place in the freezer. In a couple of hours, the fully frozen berries will be ready to transfer to a freezer bag. Don't forget to date the bag before returning to the freezer. Once thawed, frozen berries will be quite soft and should be used immediately. Dried cranberries are sold in many groceries and may be found with other dried fruits.
Tips for Preparing and Cooking Tips for Preparing CranberriesWhile not as fragile as blueberries, fresh cranberries should be treated with care. Just prior to use, place cranberries in a strainer and briefly and gently rinse under cool running water. When using frozen berries in recipes that do not require cooking, thaw well and drain prior to using. For cooked recipes, use unthawed berries since this will ensure maximum flavor. Extend the cooking time a few minutes to accommodate for the frozen berries. Cranberries retain their maximum amount of nutrients and their maximum taste when they are enjoyed fresh and not prepared in a cooked recipe. That is because their nutrients&mdash:including vitamins, antioxidants, and enzymes—are unable to withstand the temperature (350°F/175°C) used in baking. How to Enjoy A Few Quick Serving Ideas
Take advantage of cranberries' tartness by using them to replace vinegar or lemon when dressing your green salads. Toss the greens with a little olive oil and then add color and zest with a handful of raw cranberries.
To balance their extreme tartness, combine fresh cranberries with other fruits such as oranges, apples, pineapple or pears. If desired, add a little fruit juice, honey or maple syrup to chopped fresh cranberries.
For an easy-to-make salad that will immediately become a holiday favorite, place 2 cups fresh berries in your blender along with 1/2 cup of pineapple chunks, a quartered skinned orange, a sweet apple (such as one of the Delicious variety) and a handful or two of walnuts or pecans. Blend till well mixed but still chunky. Transfer to a large bowl.
Dice 3-4 stalks of celery, add to the cranberry mixture and stir till just combined.
Combine unsweetened cranberry in equal parts with your favorite fruit juice and sparkling mineral water for a lightly sweetened, refreshing spritzer. For even more color appeal, garnish with a slice of lime.
Add color and variety to your favorite recipes for rice pudding, quick breads or muffins by using dried cranberries instead of raisins.
Sprinkle a handful of dried cranberries over a bowl of hot oatmeal, barley, or any cold cereal.
Mix dried cranberries with lightly roasted and salted nuts for a delicious snack.