CURRENT USE & WHAT DOES SCIENCE SAY?

What is it typically used for today?

Psyllium’s use hasn’t changed much over the years; in fact, it is still used to treat the ailments described above. Researchers however, have begun to put some actual science behind the proposed health benefits of Psyllium. Two intensely studied health benefits of this herb are its blood glucose (in diabetics) and cholesterol-lowering effects.

Scientific Validation
In their 2009 paper, Wei, Z.H., et. al studied the cholesterol-lowering effect of Psyllium. Although, prior research had shown an association, they sought to identify if this relation was dependent on the amount of Psyllium fibre consumed (i.e. the dosage) and/or sustained in the long term (i.e. time-dependent).

They discovered that Psyllium significantly decreased total cholesterol, LDL cholesterol and HDL cholesterol concentrations, much lower than the placebo control. They also discovered that increasing the dosage further decreased the aforementioned fat profiles; however it was a logarithmic relationship meaning that greatly increasing Psyllium dosage did not produce a correspondingly large effect size. They also discovered a significant time-dependent relationship; the longer intervention, the greater the drop in total and LDL cholesterol. Additionally, long term intake of Psyllium subsequently sustained the decrease for a longer time period. The concluded by stating, “Psyllium is one of the most effective lipid-lowering agents.”

Overall, this was an extremely thorough study. The selection criteria for the subjects were quite stringent and only included strictly dieted subjects who had primary mild-to-moderate hypercholesterolemia, not secondary to another illness. Additionally, this study had a robust sample size (n=1717), lengthy intervention period (2-76 weeks), and it was randomized, double-blinded and placebo-controlled. All of these lend great legitimacy to their conclusion, “Psyllium could produce dose- and time-dependent serum cholesterol lowering effect in mild and moderate hypercholesterolemic patients and would be useful as an adjunct to dietary therapy for the treatment of hypercholesterolemia.”

Earlier this month of November, Bajorek, S.A., et al. published a paper that reviewed the effects of Psyllium supplement and a low glycemic index diet on glucose control in Type 2 diabetic patients (T2DP). In an attempt to synthesize the findings that describe Psyllium effect on blood glucose in T2DPs, using PubMed, Cochrane Library, The Natural Standard, and The Natural Medicines databases, they reviewed 7 previously conducted studies that had examined this relationship.

Although some of the studies showed that Psyllium significantly decreased postprandial plasma glucose (PPG), they admit that of the two studies that measured glycosylated hemoglobin (A1C) after Psyllium supplementation, its effect on glycosylated hemoglobin (A1C) were inconsistent between the studies. One showed a significant decrease, while the other showed no effect. Yet Bajorek, S.A., et al. concludes that results from the 7 studies suggest that Psyllium fiber may improve glycemic risk factors T2DPs.

As a whole, the review is a quite shaky. First of all, only 7 studies were reviewed. Granted, this was a function of their strict criteria to review only randomized studies. In addition, although the only articles allowed were randomized controlled studies or meta-analyses, only 3 of them were blinded. Furthermore, only 1/7 had a reasonable large sample size of 210 subjects. The second largest sample size was 40, while the other five studies had numbers below 20. Additionally, one study was underpowered to detect changes in A1C. Also, because another study observed both Psyllium and low glycemic diet effect, improper controls caused Psyllium to be confounding variable. Combined, these flaws cast huge doubt on Psyllium’s efficacy to help control blood glucose is diabetic patients. Better designed studies need to be conducted before definitive conclusions can be made.

FUN FACT: Research is currently being performed to study some associations between Psyllium and Cancer Therapy.