Fiber for Weight Control
How Much Is Usually Taken by Dieters?
Fiber supplements are one way to add fiber to a weight-loss diet. Several trials have shown that supplementation with fiber from a variety of sources accelerated weight loss in people who were following a low-calorie diet.1, 2, 3, 4 Other researchers found, however, that fiber supplements had no effect on body weight, even though it resulted in a reduction in food intake.5 Supplementation with 3 to 4 grams per day of a bulking agent called glucomannan, with or without a low-calorie diet, has promoted weight loss in overweight adults,6, 7, 8 while 2 to 3 grams per day was effective in a group of obese adolescents in another controlled trial.9 However, guar gum, another type of fiber supplement, has not been effective in controlled studies for weight loss or weight maintenance.10, 11, 12
Side Effects
The most common adverse effects of dietary fiber are minor gastrointestinal symptoms. There have been several reports of allergic reactions to psyllium. In rare cases, obstruction of the large or small intestine has occurred in people consuming wheat bran or bran cereal.
Beans, a good source of soluble fiber, also contain special sugars that are often poorly digested, leading to gas.
People with scleroderma (systemic sclerosis) should consult a doctor before taking fiber supplements or eating high-fiber diets. Although a gradual introduction of fiber in the diet may improve bowel symptoms in some cases, there have been several reports of people with scleroderma developing severe constipation and even bowel obstruction requiring hospitalization after fiber supplementation.13
Interactions with Supplements, Foods, & Other Compounds
Fiber reduces the absorption of many minerals. However, high-fiber diets also tend to be high in minerals, so the consumption of a high-fiber diet does not appear to impair mineral status. However, logic suggests that calcium, magnesium and multimineral supplements should not be taken at the same time as a fiber supplement.
Bran, which contains insoluble fiber, reduces the absorption of calcium enough to cause urinary calcium to fall.14 In one study, supplementation with 10 grams of rice bran twice a day reduced the recurrence rate of kidney stones by nearly 90% in recurrent stone formers.15 However, it is not known whether other types of bran would have the same effect. Before supplementing with bran, people should check with a doctor, because some people—even a few with kidney stones—do not absorb enough calcium. For those people, supplementing with bran might deprive them of much-needed calcium.
Interactions with Medicines
Certain medicines interact with this supplement.
 Replenish Depleted Nutrients
| none |
| Reduce Side Effects | |
| Support Medicine | none |
 Reduces Effectiveness
| |
| Potential Negative Interaction
| none |
 Explanation Required
| none |
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The information presented by TraceGains is for informational purposes only. It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. Self-treatment is not recommended for life-threatening conditions that require medical treatment under a doctor's care. For many of the conditions discussed, treatment with prescription or over the counter medication is also available. Consult your doctor, practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications. Information expires December 2025.