Psyllium Husks and Seeds
Several clinical trials have shown psyllium to be superior to other laxatives. A systematic review found psyllium husk to improve overall bowel regularity more effectively than lactulose. Psyllium has been found to be effective at increasing stool output and was found to improve the symptoms of occasional constipation increasing abdominal comfort and a sense of evacuation completeness, while reducing defecation effort. A randomized controlled trial found psyllium to have a significant effect among those with bowel irregularity and discomfort. After three months, symptom severity in the psyllium group was reduced by 90 points, compared with 49 in the placebo group. The laxative effect and gut-stimulatory effect of psyllium has been purported to be facilitated partially by muscarinic and 5-HT(4) receptor activation, which complements the laxative effect of psyllium’s fiber content. In addition, studies have also found that a 15 g dose of psyllium given 3 times per day before meals promotes healthy blood sugar and blood lipid levels.
In one animal study, giving 10 g per day of rice bran, including water soluble rice bran and rice bran fiber concentrates, resulted in significantly enhanced blood sugar balance and fasting blood sugar and lipid levels were maintained in the normal range. The extracts of rice bran have also been found to support cardiovascular health, a balanced inflammatory response, and a healthy colonic environment.
A meta-analysis of randomized controlled trials showed consumption of several grams a day of pectin promotes healthy blood fats and maintains cholesterol levels already within a normal range. Liver fat concentrations have been found to be lower in rats fed diets containing apple pectin; fecal bile acid excretion was also found to be reduced, and sterol excretion significantly increased with the addition of pectin. Rats fed pectin rich diets also had lower levels of certain blood fats than controls.
Fig (Ficus carica)
The phytochemical properties of Fig’s laxative effect are due to the bulk of seeds and fibers. In a double-blind, randomized controlled study of 20 patients with occasional functional bowel irregularity, supplementation with fig fruit increased frequency, reduced defecation time, improved abdominal comfort and heightened a sense of complete evacuation. Fig fruit supplementation also improved the symptoms of occasional irregularity, and the fruit has also been shown to maintain bulk in those with loose stools.
Prune (Prunus domestica)
Prunes or dried prunes contain 6.1 g of dietary fiber per 100 g, as well as large amounts of phenolic compounds which may aid in their efficacy for occasional constipation and glycemic support. The phenolic compounds in prunes have been found to inhibit oxidation of certain blood fat components in vitro, and thus may protect against oxidative damage; In addition, prunes have a high concentration of potassium and have been shown to support blood pressure and cardiovascular health. Another study found that 50 g of prunes, two times a day were found to be effective in helping with occasional constipation in 40 subjects enrolled in an 8-week study compared to psyllium.