Source: University of Mayland Medical Center
Dietary fiber, found in the walls of plant cells, cannot be digested by
enzymes in the human digestive tract but plays an essential role in
human health. It is found in all plant-based foods, with most whole
foods containing a combination of the two types of fiber -- soluble and
insoluble. Both types of fiber help maintain the health of the
intestinal tract and promote regular elimination of stool.
Soluble fiber attracts water and forms a gel in the digestive tract.
This slows digestion and lowers the rate of nutrient absorption (such
as starch and sugars) from the stomach and intestine. The result is a
significant reduction in cholesterol levels over time, which may help
prevent heart disease and stroke. Intake of soluble fiber may also
improve glucose tolerance in people with diabetes. Psyllium husk,
pectin, and the soft parts of fruits and dried beans and peas are
examples of soluble fiber.
Insoluble fiber, on the other hand, is the portion of plant cells
that gives the wall its structural integrity. Insoluble fiber can be
found in the peel of fruit, such as apples and grapes. It acts as a
natural laxative that speeds the passage of foods through the stomach.
It also gives stool its bulk and helps it move quickly through the
gastrointestinal tract.
Dietary fiber has been shown to play a role in the treatment of
conditions such as gastrointestinal disease, constipation, hemorrhoids,
high cholesterol, heart disease, and diabetes. However, most Americans
consume only 11 to 13 grams of dietary fiber per day -- less than half
the amount recommended by health experts.
Constipation
Many well-designed studies have concluded that fiber relieves
constipation. Studies have used wheat bran and psyllium primarily.
Fiber is believed to relieve constipation by adding bulk to stool and
speeding its transit through the gastrointestinal tract.
Diarrhea
When recommended by a healthcare practitioner, fiber can be used to
relieve mild to moderate diarrhea. Soluble fiber soaks up a significant
amount of water in the digestive tract, thereby making stool firmer and
slower to pass.
Irritable Bowel Syndrome (IBS)
Several well-designed studies have found that soluble fiber helps regulate stool frequency and consistency in people with IBS.
Hemorrhoids
Soluble fiber may be recommended by a physician to help soften stool and reduce the pain associated with hemorrhoids.
Inflammatory Bowel Disease (IBD)
In a study of people with ulcerative colitis (a type of IBD), psyllium
seeds were as effective as the prescription drug mesalamine in reducing
recurrences of the disease. In addition, a physician may recommend the
use of fiber as a bulking agent for mild to moderate cases of diarrhea
from either ulcerative colitis or Crohn's disease (another important
type of IBD).
High Cholesterol
Soluble fibers such as those in psyllium husk, guar gum, and oat
bran have a cholesterol-lowering effect when added to a low-fat,
low-cholesterol diet. Studies have shown psyllium, in particular, to be
quite effective in lowering total as well as LDL ("bad") cholesterol
levels.
Diabetes
Studies suggest that a high-fiber diet may help prevent type 2
diabetes, lower insulin and blood sugar levels, and improve cholesterol
and triglyceride levels in people with diabetes. In addition, one
well-designed study suggests that pregnant women with type 1 diabetes
are able to lower the amount of insulin they use if they eat a high
fiber diet.
Obesity
Studies and clinical reports suggest that soluble fiber (such as
psyllium, pectin, and guar gum) may enhance the sensation of fullness
and reduce hunger cravings. For these reasons, incorporating soluble
fiber into the diet may aid weight loss.
High Blood Pressure
Although not entirely conclusive, the addition of fiber (namely, 12
grams of soluble fiber per day) may help lower blood pressure.
Heart Disease
Incorporating high-fiber foods (such as oatmeal, oat bran,
psyllium, and legumes) into the diet may help lower heart disease risk.
Colon Cancer
Although initial reports were promising, studies investigating the
value of a high-fiber diet for colorectal cancer have been conflicting.
While some studies evaluating groups of people have suggested that
fiber protects against the development of colorectal cancer, most
large, better-designed studies have found only a minimal association
between fiber intake and colorectal cancer risk. In addition, fiber
does not appear to protect against the recurrence of colorectal cancer
in people who have already been treated for the condition.
Other types of Cancer
Preliminary evidence suggests that a diet high in fiber (in conjunction
with lifestyle changes and conventional medication) may help protect
against the development of certain types of cancer such as prostate,
breast, and lining of the uterus. Further studies are needed to confirm
these findings, however.
Soluble fiber is found in dried beans and peas, oats, barley, fruits, and psyllium seed husks.
Insoluble fiber is found primarily in fruits and vegetables, whole-grain products, whole grain cereals, and wheat and corn bran.
Dietary fiber is available as a supplement in several forms.
- Fiber tablets, capsules, and powders
- Bulk fiber laxatives
Pediatric
There is no specific dietary amount established for pediatric fiber
intake. Children with specific fiber needs should increase the daily
intake of fibrous foods slowly over a period of days. Fiber supplements
should only be taken under the guidance of a qualified healthcare
practitioner.
Adult
Recommended adult doses of fiber vary depending on the health condition
being treated. For general health, 25 to 35 g per day dietary fiber is
suggested.
Because supplements may have side effects or interact with medications,
they should be taken only under the supervision of a knowledgeable
healthcare provider.
In general, fiber supplements may reduce or delay the absorption of
certain medications. For this reason, it is best to refrain from taking
fiber supplements at the same time as other medications. Instead,
medications should be taken at least one hour before or between two and
four hours after taking fiber.
Fiber should always be taken with a full 8 oz glass of water. It is
also important to drink at least 6 to 8 full glasses of water
throughout the day or constipation may develop. Taking fiber
supplements without adequate liquids may cause it to swell and, in
extreme cases, cause choking. Do not take this product if you have
difficulty swallowing. People with esophageal stricture (narrowing of
the esophagus) or any other narrowing or obstruction of the
gastrointestinal tract should not take fiber supplements.
If you experience chest pain, vomiting, or difficulty swallowing or
breathing after taking fiber supplements, seek immediate medical
attention.
A potential side effect from any fiber product is gas and bloating.
Although very uncommon, allergic reactions (even anaphylaxis) to
soluble fiber may develop in people who consume these types of
supplements over a long period of time.
If you are currently being treated with any of the following
medications, you should not use fiber supplements without first talking
to your healthcare provider.
Antidepressant Medications, Tricyclics
Dietary fiber has been shown to lower the blood levels and
effectiveness of tricyclic antidepressant medications such as
amitriptyline, doxepin, and imipramine in three patients. Reduced
dietary fiber intake increased the blood levels and improved symptoms
in these patients. Individuals currently taking tricyclic medications
should consult a healthcare provider before increasing fiber intake.
Diabetes Medications
While fiber supplements may help to regulate blood sugar levels,
they may also interfere with the absorption of anti-diabetic
medications, specifically glyburide and metformin. Therefore, fiber
supplements should not be taken at the same time as this medication.
Carbamazepine
Taking soluble fiber such as psyllium with carbamazepine, a
medication used to treat seizure disorders, may decrease the absorption
and effectiveness of carbamazepine. If taking both soluble fiber and
carbamazepine, blood levels of carbamazepine should be monitored
closely by a healthcare provider.
Cholesterol-lowering Medications
Combining psyllium or other soluble fibers with cholestyramine or
colestipol (two types of cholesterol-lowering medications known as bile
acid sequestrants) may be beneficial in lowering cholesterol levels.
Individuals taking these medications should consult a healthcare
practitioner to determine whether psyllium is safe and appropriate.
On the other hand, taking fiber in the form of pectin (from fruit) and
oat bran reportedly reduces the body's ability to absorb
cholesterol-lowering medications known as "statins" (such as lovastatin
and atorvastatin), and could lead to decreased effectiveness of this
class of medications.
Digoxin
Fiber supplements may reduce the body's ability to absorb digoxin,
a medication used to regulate heart function. Therefore, fiber
supplements should not be taken at the same time as this medication.
Lithium
Reports suggest that psyllium or other soluble fibers may lower lithium
levels in the blood, reducing the effectiveness of this medication.
Lithium levels should be monitored very closely by a healthcare
provider, particularly if there is any significant change in fiber
intake.
Penicillin
In one study, the fiber supplement guar gum reduced blood levels of
penicillin. Therefore, it would be best not to take penicillin at the
same time as fiber supplements.
Alabaster O, Tang ZC, Frost A, Sivapurkar N. Potential synergism
between wheat brain and psyllium: enhanced inhibition of colon cancer. Cancer Lett . 1993;75:53–58.
Alberts DS, Martínez ME, Roe DJ, et al. Lack of effect of a high-fiber
cereal supplement on the recurrence of colorectal adenomas. N Eng J Med . 2000;342(16):1156-1162.
American Diabetes Association. Nutrition recommendations and principles for people with diabetes mellitus. Diabetes Care . 1999;22(1):S42-S45.
Anderson JW, Allgood LD, Lawrence A, et al. Cholesterol-lowering
effects of psyllium intake adjunctive to diet therapy in men and women
with hypercholesterolemia: meta-analysis of 8 controlled trials. Am J Clin Nutr . 2000;71:472-479.
Anderson JW, Allgood LD, Turner J, Oeltgen PR, Daggy BP. Effects of
psyllium on glucose and serum lipid responses in men with type 2
diabetes and hypercholesterolemia. Am J Clin Nutr. 1999;70:466-473.
Appel LJ. Nonpharmacologic therapies that reduce blood pressure: a fresh perspective. Clin Cardiol . 1999;22(Suppl. III):III1-III5.
Ashraf W, Park F, Lof J, Quigley EM. Effects of psyllium therapy on
stool characteristics, colon transit and anorectal function in chronic
idiopathic constipation. Aliment Pharmacol Ther . 1995;9:639–647.
Bazzano LA, He J, Ogden LG, Loria C, Vupputuri S, Myers L, Whelton PK.
Legume consumption and risk of coronary heart disease in US men and
women: NHANES epidemiologic follow-up study. Arch Intern Med . 2001;161(21):2573-2578.
Blumenthal M, Goldberg A, Brinckmann J. Herbal Medicine: Expanded Commission E Monographs. Newton, MA: Integrative Medicine Communications; 2000: 314-321.
Bonithon-Kopp C, Kronborg O, Giacosa A, Rath U, Faivre J. Calcium and
fibre supplementation in prevention of colorectal adenoma recurrence: a
randomised intervention trial. European Cancer Prevention Organisation
Study Group. Lancet . 2000;356(9238):1286-1287.
Botterweck AA, van den Brandt PA, Goldbohm RA. Vitamins, carotenoids,
dietary fiber, and the risk of gastric carcinoma: results from a
prospective study after 6.3 years of follow up. Cancer . 2000;88(4):737-748.
Brown L, Rosner B, Willett WW, Sacks FM. Cholesterol-lowering effects of dietary fiber: a meta-analysis. Am J Clin Nut . 1999;69(1):30-42.
Burke V, Hodgson JM, Beilin LJ, Giangiulioi N, Rogers P, Puddey IB.
Dietary protein and soluble fiber reduce ambulatory blood pressure in
treated hypertensives. Hypertension . 2001;38(4):821-826.
Chandalia M, Garg A, Lutjohann D, von Bergmann K, Grundy SM, Brinkley
LJ.. Beneficial effect of high dietary fiber intake in patients with
type 2 diabetes mellitus. N Eng J Med . 2000; 342:1392-1398.
Cohen LA. Dietary fiber and breast cancer. Anticancer Res . 1999;19(5A):3685-3688.
Compher CW, Frankel WL, Tazelaar J, Lawson JA, McKinney S, Segall S, et
al. Wheat bran decreases aberrant crypt foci, preserves normal
proliferation, and increases intraluminal butyrate levels in
experimental colon cancer. JPEN: J Paren Enteral Nutr . Sep-Oct 1999;23(5):269-277.
Etman MA. Effect of a bulk forming laxative on the bioavailability of carbamazepine in man. Drug Dev Ind Pharm . 1995;21(16):1901-1906.
Ettinger AB, Shinnar S, Sinnett MJ, Moshe SL. Carbamazepine-induced constipation. J Epilepsy . 1992;5(3):191-193.
European Scientific Cooperative on Phytotherapy (ESCOP). Psyllii semen:
Psyllium seed. Monographs on the Medicinal Uses of Plant Drugs. 1997.
Fernandez-Banares F, Hinojosa J, Sanchez-Lombrana JL, et al. Randomized
clinical trials of Platago ovata seeds (dietary fiber) as compared with
mesalamine in maintaining remission in ulcerative colitis. Am J Gastroenterol . 1999;94:427–433.
Gallaher DD, Schneeman BO. Dietary fiber. In: Ziegler EE, Filer LJ, eds. Present Knowledge in Nutrition . 7th ed. Washington, DC: International Life Sciences Institute; 1996:87-94.
Gin H, Orgerie MB, Aubertin J. The influence of guar gum on absorption of metformin from the gut in healthy volunteers. Horm Metab Res . 1989;21(2):81-83.
Goodman MT, Wilkens LR, Hankin JH, Lyu LC, Wu AH, Kolonel LN.
Association of soy and fiber consumption with the risk of endometrial
cancer. Am J Epidemiol . 1997;146(4):294-306.
Graedon J, Graedon T. Deadly Drug Interactions: The People's Pharmacy Guide . New York: St. Martin's Griffin; 1995:4, 51.
Gray DS. The clinical uses of dietary fiber. Am Fam Physician . 1995;51(2):419-426.
Hayes RB, Ziegler RG, Gridley G, et al. Dietary factors and risks for
prostate cancer among blacks and whites in the United States. Cancer Epidemiol Biomarkers Prev . 1999;8(1):25-34.
Hermansen K, Sondergaard M, Hoie L, Carstensen M, Brock B. Beneficial
effects of a soy-based dietary supplement on lipid levels and
cardiovascular risk markers in type 2 diabetic subjects. Diabetes Care . 2001;24(2):228-233.
Heyka R. Lifestyle management and prevention of hypertension. In: Rippe J, ed. Lifestyle Medicine . 1st ed. Malden, Mass: Blackwell Science; 1999:109-119.
Hillemeier C. An overview of the effects of dietary fiber on gastrointestinal transit. Pediatr . 1995:997-999.
Hu FB, Manson JE, Stampfer MJ, Colditz G, Liu S, Solomon CG, et al.
Diet, lifestyle, and the risk of type 2 diabetes mellitus in women. N Engl J Med . 2001;345(11):790-797.
Huupponen R, Seppala P, Iisalo E. Effect of guar gum, a fibre preparation, on digoxin and penicillin absorption in man. Eur J Clin Pharmacol . 1984;26(2):279-281.
Jänne PA, Mayer RJ. Chemoprevention of colorectal cancer. N Engl J Med . 2000;342(26):1960-1968.
Jenkins DJ, Kendall CW, Vuksan V. Viscous fibers, health claims, and strategies to reduce cardiovascular disease risk. Am J Clin Nut . 2001;73(3):653-654.
Jenkins DJ, Popovich DG, Kendall CW, Vidgen E, Tariq N, Ransom TP, et
al. Effect of a diet high in vegetables, fruit, and nuts on serum
lipids. Metabol . 1997;46(5):530-537.
Johnson BF, Rodin SM, Hoch K, Shakar V. The effect of dietary fiber on the bioavailability of digoxin in capsules. J Clin Pharmacol . 1987;27(7):487-490.
Kalkwarf HJ, Bell RC, Khoury JC, Gouge AL, Miodovnik M. Dietary fiber
intakes and insulin requirements in pregnant women with type 1
diabetes. J Am Diet Assoc . 2001;101(3):305-310.
Krauss RM, Eckel RH, Howard B, Appel LJ, Daniels SR, Deckelbaum RJ, et
al. AHA Scientific Statement: AHA Dietary guidelines Revision 2000: A
statement for healthcare professionals from the nutrition committee of
the American Heart Association. Circulation . 2000;102(18):2284-2299.
Kritchevsky D. Dietary fibre and cancer. Eur J Cancer Prev . 1997;6:435-441.
Kurtz RC, Zhang ZF. Gastric cardia cancer and dietary fiber. Gastroenterology . 2001;120(2):568-70
Lantner RR, Espiritu BR, Zumerchik P, Tobin MC. Anaphylaxis following ingestion of a psyllium-containing cereal . JAMA . 1990;264(19):2534-2536.
Le Marchand L, Wilkens LR, Hankin JH, Kolonel LN, Lyu LC. Independent
and joint effects of family history and lifestyle on colorectal cancer
risk: Implications for prevention. Cancer Epidemiol Biomarkers Prevent .1999;8:45-51.
Liu S, Manson JE, Stampfer MJ, Hu FB, Giovannucci E, Colditz GA, et al.
A prospective study of whole-grain intake and risk of type-2 diabetes
mellitus in women. Am J Pub Health. 2000;90:1409-1415.
Lu LJ, Anderson KE, Grady JJ, Kohen F, Nagamani M. Decreased ovarian
hormones during a soya diet: implications for breast cancer prevention. Can Res . 2000;60(15):4112-4121.
Ludwig DS, Pereira MA, Kroenke CH, Hilner JE, Van Horn L, Slattery ML,
Jacobs DR Jr. Dietary fiber, weight gain, and cardiovascular disease
risk factors in young adults. JAMA .1999:282(16):1529-1546.
Marlett JA, et al. Mechanism of serum cholesterol reduction by oat bran. Hepatology . 1994;20:1450-1457.
Mayne ST, Risch HA, Dubrow R, Chow WH, Gammon MD, Vaughan TL, et al.
Nutrient intake and risk of subtypes of esophageal and gastric cancer. Cancer Epidemiol Biomarkers Prev . 2001;10(10):1055-1062.
McGuffin M, ed. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, 1997.
McRorie JW, Daggy BP, Morel JG, Diersing PS, Miner PB, Robinson M.
Psyllium is superior to docusate sodium for treatment of chronic
constipation. Aliment Pharmacol Ther . 1998;12:491–497.
Michels KB, Giovannucci E, Joshipura KJ, Rosner BA, Stampfer MJ, Fuchs
CS, et al. Prospective study of fruit and vegetable consumption and
incidence of colon and rectal cancers. J Natl Cancer Inst . 2000;92(21):1740-1752.
Murray MT, Pizzorno JE. Role of dietary fiber in health and disease. In: Pizzorno JE, Murray MT, eds. Textbook of Natural Medicine . Vol 1. 2nd ed. Edinburgh: Churchill Livingstone; 1999:507-516.
National Cholesterol Education Program. Executive summary of the third
report of the National Cholesterol Education Program (NCEP) expert
panel on detection, evaluation, and treatment of high blood cholesterol
in adults (Adult Treatment Panel III). JAMA . 2001;285(19):2486-2497.
Perlman BB. Interaction between lithium salts and ispaghula husk [letter]. Lancet . 1990;355:416.
Persson PG, Ahlbom A, Hellers G. Diet and inflammatory bowel disease: a case-control study. Epidemiol . 1992;3(1):47-52.
Potischman N, Swanson CA, Coates RJ, Gammon MD, Brogan DR, Curtin J, et
al. Intake of food groups and associated micronutrients in relation to
risk of early-stage breast cancer. Int J Cancer. 1999;82(3):315-321.
Richter WO, Jacob BG, Schwandt P. Interaction between fibre and lovastatin. Lancet . 1991;338;706.
Rodrigues-Moran M, Guerrero-Romero F, Lazcano-Burciaga G. Lipid- and
glucose-lowering efficacy of Plantago Psyllium in type II diabetes. J Diabetes Complications. 1998;12:273–278.
Schatzkin A, Lanza E, Corle D, Lance P, Iber F, Caan B, et al. Lack of
effect of a low-fat, high-fiber diet on the recurrence of colorectal
adenomas. N Engl J Med. 2000;342(16):1149-1155.
Shils ME, Olson JA, Shike M, eds. Modern Nutrition in Health and Disease . 9th ed. Media, Pa: Williams & Wilkins; 1999.
Soffer EE. Constipation: an approach to diagnosis, treatment, referral. Cleve Clin J Med . 1999;66(1):41-46.
Soler M, Bosetti C, Franceschi S, Negri E, Zambon P, Talamini R, et al.
Fiber intake and the risk of oral, pharyngeal, and esophageal cancer. Int J Cancer . 2001;91(3):283-287.
Spence JD, Huff MW, Heidenheim P et al. Combination therapy with
colestipol and psyllium mucilloid in patients with hyperlipidemia. Ann Intern Med . 1995;123:493-499.
Stampfer MJ, Hu FB, Manson JE, Rimm EB, Willett WC. Primary prevention
of coronary heart disease in women through diet and lifestyle. N Engl J Med. 2000;343(1):16-22.
Stewart DE. High-fiber diet and serum tricyclic antidepressant levels. J Clin Psychopharmacol. 1992;12:438-440.
Tariq N, Jenkins D, Vidgen E, Fleshner N, Kendall CW, Story JA, et al.
Effect of soluble and insoluble fiber diets on serum prostate specific
antigen in men. J Urol . 2000;163:114-118.
Terry P, Lagergren J, Ye W, Wolk A, Nyren O. Inverse association
between intake of cereal fiber and risk of gastric cardia cancer. Gastroenterology . 2001;120(2):387-391.
Toutoungi M, Schulz P, Widmer J, et al. Probable interaction of psyllium and lithium. Therapie . 1990;45(4):358-360.
Tuomilehto J, Lindstrom J, Eriksson JG, Valle TT, Hamalainen H,
Ilanne-Parikka P, et al. Prevention of type 2 diabetes mellitus by
changes in lifestyle among subjects with impaired glucose tolerance. N Engl J Med . 2001;344(18):1343-1350.
Turley SD, Daggy BP, Dietschy JM. Effect of feeding psyllium and
cholestyramine in combination on low density lipoprotein metabolism and
fecal bile acid excretion in hamsters with dietary-induced
hypercholesterolemia. J Cardiovasc Pharmacol . 1996;27:71-79.
Turnbull WH, Thomas HG. The effect of a Plantago ovata seed containing
preparation on appetite variables, nutrient and energy intake. Int J Obes Relat Metab Disord. 1995;19:338-342.
Vaswani SK, Hamilton RG, Valentine MD, Adkinson NF Jr. Psyllium laxative-induced anaphylaxis, asthma, and rhinitis. Allergy . 1996;51(4):266-268.
Wald A. Constipation. Med Clin North America . 2000;84(5):1231-1246.
Wursch P, Pi-Sunyer FX. The role of viscous soluble fiber in the
metabolic control of diabetes. A review with special emphasis on
cereals rich in beta-glucan. Diabetes Care . 1997; 20:1774-1780.
- Review Date:
4/1/2002
- Reviewed By: Participants in the review process include: Ruth
DeBusk, RD, PhD, Editor, Nutrition in Complementary Care, Tallahassee,
FL; Jacqueline A. Hart, MD, Department of Internal Medicine,
Newton-Wellesley Hospital, Harvard University and Senior Medical Editor
Integrative Medicine, Boston, MA; Gary Kracoff, RPh (Pediatric Dosing
section February 2001), Johnson Drugs, Natick, Ma; Steven Ottariono,
RPh (Pediatric Dosing section February 2001), Veteran's Administrative
Hospital, Londonderry, NH. All interaction sections have also been
reviewed by a team of experts including Joseph Lamb, MD (July 2000),
The Integrative Medicine Works, Alexandria, VA;Enrico Liva, ND, RPh
(August 2000), Vital Nutrients, Middletown, CT; Brian T Sanderoff, PD,
BS in Pharmacy (March 2000), Clinical Assistant Professor, University of Mayland School of Pharmacy; President, Your Prescription for
Health, Owings Mills, MD; Ira Zunin, MD, MPH, MBA (July 2000),
President and Chairman, Hawaii State Consortium for Integrative
Medicine, Honolulu, HI.
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