. Fortunately for those of us with IC, cranberries share some healthful qualities with other less acid and more bladder-friendly botanical relatives.
The Vaccinium species
Cranberries and blueberries are, in botanical terms, cousins. They are both members of the genus Vaccinium, a group of plants native to North America. This family includes bilberries, highbush and lowbush blueberries, bog bilberries, and cranberries. For centuries, fruits from these plants have been used medicinally as well as for food by Native Americans.
In recent years though, the fruit of this family of plants has attracted the attention of scientists. The berries are high in powerful antioxidants and they may possess anti-aging and anti-cancer properties. Urologists have also been interested in some of these species because the berries appear to contain anti-infective substances useful in controlling bacterial bladder infections. Here is a quick overview of the attributes of several of these cranberry “cousins”:
The bitter and unattractive common bilberry (V. myrtillus) fruit has for many years been a popular folk medicine used to ease complaints of mild diarrhea and sore throats. Another similar species, the bog bilberry (V. uliginosum), has been traditionally used for bladder irritation as well as diarrhea . Both of these berries can be found in dietary supplements aimed at consumers with bladder complaints.
Both types of berries are very high in tannins (12% to 20%) however, one of the irritating constituents of coffee. Bilberries also contain citric acid, benzoic acid, and salicylic acid– all substances well known to trigger bladder symptoms for IC patients. Teas made with these berries may also upset the stomach if consumed in large quantities. IC patients should probably approach these two with caution.
These exceedingly acidic berries were called “i-bimi” or “bitter fruit” by the Pequot Indians of Cape Cod in the 1700’s. Since then, cranberries have become a folk remedy for women’s bladder infections. But it wasn’t until 1994 that scientific evidence emerged that drinking cranberry juice could really prevent bladder infections. With that finding, many doctors naturally assumed that it was the acidity of cranberry juice that fought bacteria. But research indicates that the cranberry’s infection fighting mechanism is much more complex than that. It seems that other substances in cranberries help disinfect urine , and at least one substance actually prevents bacteria from clinging to the bladder surface, making the organisms easier to flush out [3,4].
The alpine cranberry (V. vitis-idaea), is dried and sold in health food stores as a dietary supplement. It has a urine-disinfecting effect that appears to be based on the hydroquinones which are released in the urinary tract. A few people with relatively mild cases of IC have reported some luck in reducing their bladder symptoms by taking dried cranberries. Dried cranberries may be less acidic than fresh ones. Nonetheless, many IC sufferers still find them intolerable. If you want to experiment with dried cranberries though, here’s a tip that might help:
Hydroquinones will only work in an alkaline environment . That means avoid taking dried cranberries with food that increases the acid content of the urine (meats and fish for instance). Milk or baking soda may help alkalinize the urine. You can buy litmus paper and test the acid/base balance of your urine.
Highbush and Lowbush Blueberries
The wild lowbush blueberry plant, (V. augustifolium) produces small, sweet, blue berries that are often marketed as “wild blueberries”. More common in stores are highbush blueberries (V. corybosum). These are the cultivated blueberry and are planted and maintained much as an orchard would be. Most blueberries in North American grocery stores are highbush blueberries.
According to some, both kinds of blueberries are a real bonanza of health benefits. And no wonder. Dr. Ronald Prior, who studies antioxidants in food at the Tufts University Human Nutrition Research Center states, “In general, blueberries are one of the richest sources of antioxidant phytonutrients of the fresh fruits and vegetables we have studied.” One study found that blueberries had more than twice the antioxidant content of strawberries or raspberries and more importantly, their antioxidant content did not diminish with storage. Antioxidants in foods are thought to be important for many reasons: they may delay effects of aging, help prevent some cancers and combat heart disease among other things.
What makes blueberries especially valuable to IC patients though, is that they are tasty and sweet and have none of the cranberry’s awesome acidity. Half a cup is only 41 calories but has 2 grams of fiber and 9 mg. of vitamin C (about 16% of the RDA). At last! A health promoting food we can eat! Blueberries are well tolerated by many people with IC. Their only apparent drawback is their oxalate content. (Oxalates in food may exacerbate some cases of vulvodynia, an IC-associated condition involving pain in the vulvar area. Only about 15% of IC patients have vulvodynia).
Here are some other possible health benefits of blueberries which are currently under investigation:
In an animal study funded by the National Institute of Aging and the U.S. Dept. of Agriculture, dietary supplementation with blueberries apparently reversed the lack of balance, lack of coordination and failing memory associated with aging. A second study with animals confirmed the results and also demonstrated measurable improvements in the status and functioning of the central nervous system . More studies, including trials with humans are planned. In one small placebo controlled, crossover trial with humans, blueberry extracts had a positive effect on tired eyes and appeared to prevent weak eyesight .
1. Avorn J, Monane M., et al; Reduction of bacteriuria and pyuria after ingestion of cranberry juice; Journal of the American Medical Assn.; 1994; Vol. 271; pp. 751-754.
2. PDR (Physicians Desk Reference) for Herbal Medicines; Gruenwald J.,Brendler T., Jaenicke C., eds.; Medical Economics Co., Montvale NJ; 1998; pp 1201-1204.
3. Ofek I, Goldhar J, et al.; Anti-Escherichia coli adhesin activity of cranberry and blueberry juices; New England Journal of Medicine; 1991; Vol. 324; pg. 1599.
4. Howell A, Der Marderosian A, Foo LY; Inhibition of the adherence of P-fimbriated Escherichia coli to uroepithelial-cell surfaces by proanthocyanidin extracts from cranberries; New England Journal of Medicine; 1994; Vol. 339, No. 15; letter.
5. Prior R; Antioxidant capacity as influenced by total phenolic and anthocyanin content, maturity and variety of vaccinium species; Journal of Agricultural and Food Chemistry; 1998; Vol. 46, No. 7; pg. 2686.
6. Joseph J, Shukitt-Hale B., Denisova N.A., et al.; Reversal of age-related declines in neuronal signal transduction, cognitive, and motor behavioral deficits with blueberry, spinach, or strawberry dietary supplementation; Journal of Neuroscience; 1999; Vol. 19, No. 18; pp. 8114- 8121.
7. Bickford P.C., Shukitt-Hale B., Gould T.J., et al.; Reversal of age-related declines in CNS neuro-transmission with diets supplemented with fruit or vegetable extracts; Society of Neuroscience Abstracts; 1999; Vol. 24, pg 2157.
8. Osami Kajimoto; Blueberries and eyesight; Food Style 21; Vol. 3, no. 3; March 1999 (In Japanese, translation courtesy North American Blueberry Council).
Recipes of the Month
For breakfast try fresh blueberries in pancakes or waffles, on home-made granola cereal, or top toasted bagels with cottage cheese and berries. For desserts, nothing beats blueberry pie or a blueberry buckle. Here are some other blueberry treats.
Purple Passion Smoothie
– serves 2
- 1/2 cup blueberries — fresh, washed and chilled
- 1-1/2 cups vanilla ice cream
- 1/2 cup cold milk
- 2 chilled glasses
- Place all ingredients in a blender and process until smooth and frothy, about 45 seconds.
- Pour into chilled glasses and serve.
Makes about 2-1/4 cups. Frozen blueberries work fine too.
Per serving: 219 Calories, 11g Total Fat; 7g Protein
Variations: I’ve tried substituting cottage cheese curds for about 1/4 cup of the ice cream (just curds, not whey, rinsed under running water). On occasion I’ve also made this more of a “meal” by adding 2 Tbsp. of pure high-protein egg white powder.
Blueberry Maple Mousse
Recipe adapted from Massachusetts Maple Producers Assn.
– serves 5
- 6 egg yolks
- 1 pint heavy whipping cream
- 3/4 cup maple syrup — heated
- 1 pint blueberries
- Beat yolks in the top of a double boiler until thick.
- Beat in hot syrup. Put over simmering water and cook, beating constantly until slightly thickened.
- Cool slightly, then refrigerate 2 hours.
- Beat whipping cream until it forms stiff peaks and fold into the cool yolk mixture.
- Fold in half of the berries.
- Pour into 1-1/2 qt. dish or mold, or pour into individual cups or glasses.
- Freeze overnight.
- Before serving, garnish with remainder of berries.
Per serving: 556 Calories; 208g Total Fat; 28g Protein
Blueberry Coffeecake Recipe
adapted from Cooking Light Magazine, Jul-Aug 1995
– serves 8
- 1/4 cup stick margarine, softened
- 8 oz. nonfat cream cheese
- 1 cup sugar
- 1 egg
- 1 cup all-purpose flour
- 1-1/4 tsp. baking powder
- 1/4 tsp. salt
- 1 tsp. vanilla extract
- 2 cups blueberries
- Vegetable cooking spray
- 2 Tbsp. sugar
- 1 tsp. ground cinnamon or 1/2 tsp. ground nutmeg
- Cream margarine and cheese together.
- Gradually add 1 cup sugar, beating at medium speed of a mixer until well-blended.
- Add egg; beat well.
- Combine flour, baking powder, and salt; stir into creamed mixture.
- Stir in vanilla; fold in berries.
- Pour into a 9-inch round cake pan coated with cooking spray.
- Combine 2 tablespoons sugar and cinnamon; sprinkle over batter.
- Bake at 350 degrees for 1 hour; let cool.
Per serving: 313 Calories (kcal); 11g Total Fat; 5g Protein