Consumption of fibre supplements may be for improving dietary intake, lowering blood cholesterol, alleviating irritable bowel syndrome, reducing the risk of colon cancer, and increasing feelings of satiety.
Excessive fibre intake can lead to fluid imbalance, dehydration, mineral deficiencies, nutrient and drug interactions, and other medical problems.
A study of 1429 men and women over six months showed that a high-fibre cereal (wheat bran) supplement had no protective effect on recurring colorectal adenomas.
One study of 58 men and women with uncomplicated diverticulitis in a double-blind controlled trial concluded that common doses of wheat bran and a psyllium-derived supplement provided relief of constipation only, with no other observable effects.
As a supplement, partially hydrolysed guar gum (PHGG - completely soluble, fully fermentable[11]) has been shown to be quite effective in clinical trials for decreasing IBS symptoms such as abdominal pain and generally improving quality of life for sufferers well beyond treatment.
[12] Acacia senegal fiber (gum arabic - completely soluble, fully fermentable) has also been shown to have a prebiotic effect in the gut, significantly increasing Bifidobacteria and Lactobacilli after 4 weeks of consumption.
[17] This is because dietary fibre may be able to displace available calories and nutrients, requires more time for chewing (thereby slowing intake rate and inducing satiety), and reduces the efficiency of absorption in the small intestine.
[17][18] Supplemental forms of fibre have been shown to potentially assist weight management by increasing satiety,[19][20][21] decreasing the absorption rate of starches and sugars, and binding to lipids in the small intestine thereby reducing serum triglycerides and chylomicron.
[24] Abruptly adding elevated amounts of fibre to the diet too quickly can lead to intestinal gas, diarrhea, abdominal bloating, cramping, and constipation.
The risk of intestinal obstruction from insoluble fiber in susceptible individuals,[26] fluid imbalance leading to dehydration and mineral deficiencies may increase if more than 50 g of fibre is ingested per day.
Findings from the latest National Diet and Nutrition Survey reveal that the average Briton consumes 18g of fiber each day; however, this is significantly below the recommended intake of 30g.