What do the advocates say?*
Unlike laxatives, fibre can truly help regulate bowel patterns. If you choose to take a
fibre supplement, be sure you don’t inadvertently purchase a laxative supplement
instead. The labels on both types of supplements may say something like “regulates bowel
patterns.” While the featured ingredient of fibre supplements will likely be an
ingredient such as psyllium, the featured ingredient of laxatives tend to be herbal-based.
Such supplements are designed only for short-term constipation.
While there is weak evidence that fibre may promote a feeling of fullness, it seems to be
necessary to use it in conjunction with a diet and exercise programme in order to be effective
for contributing to weight loss.
The best way to get fibre is from food. However, if you don’t include enough
fibre-rich food in your diet and choose to use a fibre supplement instead, choose a product
that has different types of fibre in it—both soluble and insoluble. When taking a fibre
supplement, be sure to stay well hydrated.
Are there any side effects or interactions?
While people can be allergic to certain high-fibre
foods (most commonly wheat), high-fibre diets are more likely to improve health than
cause any health problems. Beans, a good source of
soluble fibre, also contain special sugars that are often poorly digested, leading to wind.
Special enzyme products are now available in supermarkets to
reduce this problem by improving digestion of these sugars.
Fibre reduces the absorption of many minerals. However, high-fibre diets also tend to be
high in minerals, so the consumption of a high-fibre 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 fibre supplement.
Bran, an insoluble fibre, reduces the absorption of calcium enough to cause urinary calcium
to fall.13 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.14 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.
People with scleroderma (systemic sclerosis) should consult a doctor before taking fibre
supplements or eating high-fibre diets. Although a gradual introduction of fibre 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 hospitalisation after fibre supplementation.15
Are there any drug
interactions?
Certain medicines may interact with fibre. Refer to drug
interactions for a list of those medicines.
References
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