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Citrus fruits are well known for providing ample amounts of vitamin C. But they also supply bioflavonoids, substances that are not required for life but that may improve health. The major bioflavonoids found in citrus fruits are diosmin, hesperidin, rutin, naringin, tangeretin, diosmetin, narirutin, neohesperidin, nobiletin, and quercetin.
This article addresses the first five bioflavonoids listed above. Please see the article on quercetin for information on this supplement. A modified form of rutin, oxerutin, is also discussed in its own article.
Citrus bioflavonoids and related substances are widely used in Europe to treat diseases of the blood vessels and lymph system, including hemorrhoids, chronic venous insufficiency, easy bruising, nosebleeds, and lymphedema following breast cancer surgery. These compounds are thought to work by strengthening the walls of blood vessels.
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Requirements/Sources
Citrus fruits contain citrus bioflavonoids in varying proportions. Even different brands of citrus juice may vary widely in their bioflavonoid concentrations and composition.1 For use as a supplement, bioflavonoids are extracted either from citrus fruits or other plant sources, such as buckwheat.
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Therapeutic Dosages
A typical dosage of citrus bioflavonoids is 500 mg twice daily. The most studied citrus bioflavonoid treatment is a special combination of diosmin (90%) and hesperidin (10%).
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Therapeutic Uses
Double-blind trials suggest that a special micronized combination preparation of diosmin and hesperidin may be helpful for hemorrhoids.2–6
Diosmin and hesperidin, as well as the bioflavonoid rutin, may also be helpful for chronic venous insufficiency, a condition in which the veins in the legs begin to weaken.7–10,34,35
At least one good double-blind trial found diosmin and hesperidin also to be helpful for individuals who develop bruises or nosebleeds easily.13
Citrus bioflavonoids have also been tried, with some success, for treating lymphedema (arm swelling) following breast cancer surgery.14
Note: Do not use bioflavonoid combinations containing tangeretin if you are taking tamoxifen for breast cancer.
In addition, highly preliminary evidence suggests that citrus bioflavonoids may help reduce cholesterol levels,15,16 control inflammation,17 benefit individuals with diabetes,18 reduce allergic reactions,19 and prevent cancer.20
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What Is the Scientific Evidence for Citrus Bioflavonoids?
Hemorrhoids
A 2-month double-blind placebo-controlled trial of 120 individuals with recurrent hemorrhoid flare-ups found that treatment with combined diosmin and hesperidin significantly reduced the frequency and severity of hemorrhoid attacks.21 Another double-blind placebo-controlled trial of 100 individuals had positive results with the same bioflavonoids in relieving symptoms once a flare-up of hemorrhoid pain had begun.22 A 90-day double-blind trial of 100 individuals with bleeding hemorrhoids also found significant benefits for both treatment of acute attacks and prevention of new ones.23 Finally, this bioflavonoid combination was found to compare favorably with surgical treatment of hemorrhoids.24 However, less impressive results were seen in a double-blind placebo-controlled study in which all participants were given a fiber laxative with either combined diosmin and hesperidin or placebo.25
Chronic Venous Insufficiency
A two-month, double-blind, placebo-controlled trial of 200 individuals with relatively severe chronic venous insufficiency found that treatment with diosmin/hesperidin significantly improved symptoms as compared to placebo.34
Another double-blind, placebo-controlled trial of diosmin/hesperidin enrolled 101 individuals with relatively mild chronic venous insufficiency.35 The results showed little difference between the two groups; the authors theorize that diosmin/hesperidin might be generally more effective in severe chronic venous insufficiency.
A 2-month, double-blind, placebo-controlled trial evaluated the effects of diosmin/hesperidin in 107 individuals with nonhealing leg ulcers (sores) caused by venous insufficiency or other conditions.26 The results indicated that treatment significantly improved the rate of healing.
Also, a 3-month, double-blind, placebo-controlled trial of 67 individuals evaluated buckwheat tea (a good source of rutin) for chronic venous insufficiency.27 The results showed less leg swelling in the treated group.
Easy Bruising
Some individuals bruise particularly easily due to fragile capillaries. A 6-week double-blind placebo-controlled study of 96 people with this condition found that combined diosmin and hesperidin decreased symptoms of capillary fragility, such as bruising and nosebleeds.28
Two rather poorly designed studies from the 1960s found benefits with a combination of vitamin C and citrus bioflavonoids for decreasing bruising in collegiate athletes.29
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Safety Issues
Extensive investigations of diosmin and hesperidin have found them to be essentially nontoxic and free of drug interactions.30 The combination has been given to 50 pregnant women in a research study, without apparent harm to mothers or babies.31
However, the citrus bioflavonoid tangeretin appears to interfere with the action of tamoxifen, a drug used to treat breast cancer.32
One highly preliminary study suggests that citrus bioflavonoids in the diet of pregnant women might increase the risk of infant leukemia; however, hesperidin did not produce this effect, and diosmin was not tested.33
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Interactions You Should Know About
If you are taking tamoxifen for breast cancer, you should avoid citrus fruits and juices and the citrus bioflavonoid tangeretin.
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References
1. Ross SA, Ziska DS, Zhoa K, et al. Variance of common flavonoids by brand of grapefruit juice. Fitoterapia. 2000;71:154–161.
2. Godeberge P. Daflon 500 mg in the treatment of hemorrhoidal disease: a demonstrated efficacy in comparison with placebo. Angiology. 1994;45:574–578.
3. Cospite M. Double-blind, placebo-controlled evaluation of clinical activity and safety of Daflon 500 mg in the treatment of acute hemorrhoids. Angiology. 1994;45:566–573.
4. Thanapongsathorn W, Vajrabukka T. Clinical trial of oral diosmin (DaflonW) in the treatment of hemorrhoids. Dis Colon Rectum. 1992;35:1085–1088.
5. Misra MC, Parshad R. Randomized clinical trial of micronized flavonoids in the early control of bleeding from acute internal haemorrhoids. Br J Surg. 2000;87:868–872.
6. Ho YH, Tan M, Seow-Choen F. Micronized purified flavonidic fraction compared favorably with rubber band ligation and fiber alone in the management of bleeding hemorrhoids: randomized controlled trial. Dis Colon Rectum. 2000;43:66–69.
7. Tsouderos Y. Venous tone: are the phlebotonic properties predictive of a therapeutic benefit? A comprehensive view of our experience with Daflon 500 mg. Z Kardiol. 1991;80(suppl 7):95–101.
8. Ihme N, Kiesewetter H, Jung F, et al. Leg oedema protection from a buckwheat herb tea in patients with chronic venous insufficiency: a single-centre, randomised, double-blind, placebo-controlled clinical trial. Eur J Clin Pharmacol. 1996;50:443–447.
9. Guilhou JJ, Dereure O, Marzin L, et al. Efficacy of Daflon 500 mg in venous leg ulcer healing: a double-blind, randomized, controlled versus placebo trial in 107 patients. Angiology. 1997;48:77–85.
10. Guilhou JJ, Fevrier F, Debure C, et al. Benefit of a 2-month treatment with a micronized, purified flavonoidic fraction on venous ulcer healing. A randomized, double-blind, controlled versus placebo trial. Int J Microcirc Clin Exp. 1997;17(Suppl 1):21–26.
11. Guilhou JJ, Dereure O, Marzin L, et al. Efficacy of Daflon 500 mg in venous leg ulcer healing: a double-blind, randomized, controlled versus placebo trial in 107 patients. Angiology. 1997;48:77–85.
12. Guilhou JJ, Fevrier F, Debure C, et al. Benefit of a 2-month treatment with a micronized, purified flavonoidic fraction on venous ulcer healing. A randomized, double-blind, controlled versus placebo trial. Int J Microcirc Clin Exp. 1997;17(Suppl 1):21–26.
13. Galley P, Thiollet M. A double-blind, placebo-controlled trial of a new veno-active flavonoid fraction (S 5682) in the treatment of symptomatic capillary fragility. Int Angiol. 1993;12:69–72.
14. Pecking AP, Fevrier B, Wargon C, et al. Efficacy of Daflon 500 mg in the treatment of lymphedema (secondary to conventional therapy of breast cancer). Angiology. 1997;48:93–98.
15. Lee SH, Park YB, Bae KH, et al. Cholesterol-lowering activity of naringenin via inhibition of 3-hydroxy-3-methylglutaryl coenzyme A reductase and acyl coenzyme A: cholesterol acyltransferase in rats. Ann Nutr Metab. 1999;43:173–180.
16. Shin YW, Bok SH, Jeong TS, et al. Hypocholesterolemic effect of naringin associated with hepatic cholesterol regulating enzyme changes in rats. Int J Vitam Nutr Res. 1999;69:341–347.
17. Emim JA, Oliveira AB, Lapa AJ. Pharmacological evaluation of the anti-inflammatory activity of a citrus bioflavonoid, hesperidin, and the isoflavonoids, duartin and claussequinone, in rats and mice. J Pharm Pharmacol. 1994;46:118–122.
18. Manuel y Keenoy B, Vertommen J, De Leeuw I. The effect of flavonoid treatment on the glycation and antioxidant status in Type 1 diabetic patients. Diabetes Nutr Metab. 1999;12:256–263.
19. Middleton E Jr, Drzewiecki G, Tatum J. The effects of citrus flavonoids on human basophil and neutrophil function. Planta Med. 1987;53:325–328.
20. So FV, Guthrie N, Chambers AF, et al. Inhibition of human breast cancer cell proliferation and delay of mammary tumorigenesis by flavonoids and citrus juices. Nutr Cancer. 1996;26:167–181.
21. Godeberge P. Daflon 500 mg in the treatment of hemorrhoidal disease: a demonstrated efficacy in comparison with placebo. Angiology. 1994;45:574–578.
22. Cospite M. Double-blind, placebo-controlled evaluation of clinical activity and safety of Daflon 500 mg in the treatment of acute hemorrhoids. Angiology. 1994;45:566–573.
23. Misra MC, Parshad R. Randomized clinical trial of micronized flavonoids in the early control of bleeding from acute internal haemorrhoids. Br J Surg. 2000;87:868–872.
24. Ho YH, Tan M, Seow-Choen F. Micronized purified flavonidic fraction compared favorably with rubber band ligation and fiber alone in the management of bleeding hemorrhoids: randomized controlled trial. Dis Colon Rectum. 2000;43:66–69.
25. Thanapongsathorn W, Vajrabukka T. Clinical trial of oral diosmin (DaflonW) in the treatment of hemorrhoids. Dis Colon Rectum. 1992;35:1085–1088.
26. Guilhou JJ, Dereure O, Marzin L, et al. Efficacy of Daflon 500 mg in venous leg ulcer healing: a double-blind, randomized, controlled versus placebo trial in 107 patients. Angiology. 1997;48:77–85.
27. Ihme N, Kiesewetter H, Jung F, et al. Leg oedema protection from a buckwheat herb tea in patients with chronic venous insufficiency: a single-centre, randomised, double-blind, placebo-controlled clinical trial. Eur J Clin Pharmacol. 1996;50:443–447.
28. Galley P, Thiollet M. A double-blind, placebo-controlled trial of a new veno-active flavonoid fraction (S 5682) in the treatment of symptomatic capillary fragility. Int Angiol. 1993;12:69–72.
29. Miller MJ. Injuries to athletes. Evaluation of ascorbic acid and water soluble citrus bioflavonoids in the prophylaxis of injuries in athletes. Med Times. 1960;88:313–316.
30. Meyer OC. Safety and security of Daflon 500 mg in venous insufficiency and in hemorrhoidal disease. Angiology. 1994;45:579–584.
31. Buckshee K, Takkar D, Aggarwal N. Micronized flavonoid therapy in internal hemorrhoids of pregnancy. Int J Gynaecol Obstet. 1997;57:145–151.
32. Bracke ME, Depypere HT, Boterberg T, et al. Influence of tangeretin on tamoxifen's therapeutic benefit in mammary cancer. J Natl Cancer Inst. 1999;91:354–359.
33. Strick R, Strissel PL, Borgers S, et al. Dietary bioflavonoids induce cleavage in the MLL gene and may contribute to infant leukemia. Proc Natl Acad Sci. 2000;97:4790–4795.
34. Laurent R, Gilly R, Frileux C. Clinical evaluation of a venotropic drug in man. Example of Daflon 500 mg. Int Angiol. 1988;7:39-43.
35. Danielsson G, Jungbeck C, Peterson K, et al. A randomised controlled trial of micronised purified flavonoid fraction vs placebo in patients with chronic venous disease. Eur J Vasc Endovasc Surg. 2002;23:73–76.
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