Sunday, November 28, 2010

WHAT IS PSYLLIUM?

Psyllium is the husk of a plant seed and it is a top herb used in weight control and for general intestinal health. It has a capacity for high water retention, and has the ability to swell up to 50 times its weight. There are four main Psyllium products; Psyllium Seeds, Psyllium Husk, Psyllium Husk Powder, and Psyllium Industrial Powder. Psyllium Husk and Psyllium Husk powder are the most important dietary products, and carry the strongest nutritional benefits.

Thursday, November 25, 2010

HISTORY & TRADITIONAL USE

Where did it originate?

Psyllium is the common name used for over 200 species of the plant genus Plantago. Two species include; P. Ovata, P. arenaria.

The common name for P. Ovata in India is “Isabgol,” and this specie is indigenous to the Mediterranean region and West Asia. It is also distributed from Canary Islands across Southern Spain, North Africa, Middle East and North-Western Asia.

P. arenaria is produced commercially in several European countries such as, the former Soviet Union, Pakistan, and India.

How long has it been used?

Psyllium has a long history of use throughout the world. In India the use of P. Ovata dates back to the Ayurveda System of Medicine in 1500BC. Similarly, the Chinese have used it in traditional medicine for thousands of years, whereas European use of the herb dates back centuries. Psyllium became common in North American healing only near the end of the twentieth century.

Who/What cultures were using it and for what purposes?

Since 1500BC, Psyllium has been used for constipation by both the Indian and the Chinese. The traditional herbal systems of China and India also used it to treat diarrhea, hemorrhoids, bladder problems, and high blood pressure. It was also used topically by herbalists to treat skin irritations, such as; poison ivy reactions, insect bites and stings. Europeans and North Americans began using Psyllium for cholesterol, and blood glucose-lowering effects.

How was it administered?

Typically, Psyllium was administered in powder, flakes or granular form. These would then be diluted in liquids and drank or sprinkled over meals. Only recently have they been made available in tablets, capsules and liquid form, although the other forms are still widely used.

FUN FACT: India dominates the world market in the production and export of Psyllium.

ACTIVE COMPONENT AND PREPARATION

What are the herb’s active constituents? Is it a combination of multiple components or one main compound?

The active component of Psyllium is a highly-branched arabinoxylan consisting of a xylose backbone and arabinose- and xylose-containing side chains. The arabinoxylan in Psyllium however, has a still unidentified unique structural feature that prevents fermentation by colonic microflora. This is the gel-forming component that is responsible for the laxative and cholesterol-lowering properties of Psyllium. This one main compound is also believed to be the active component responsible for Psyllium’s other health benefits.


How is the herbal treatment typically prepared and administered? (i.e. standardized capsule, extract, spray, oil etc...)

First, the raw material is fumigated using chemical reagents like Methyl Bromide, followed by mechanical cleaning (removal of foreign particles). Next, the mixture is ground, after which it passes through a de-husking processes that help to obtain high yields of pure Psyllium seed husk. These processes include milling which causes the husk to be separated from the non-husk portion of the Psyllium seed. The husk is then passed through gravity separators for further purification. Finally, the powdered husk is manually mixed, custom packaged and shipped off. Today it is commonly administered as a powder, although it is also available in capsules.

FUN FACT: The process of discovering the active components involved examining soft human stool. Imagine the horror!!!

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.

ADVERSE EFFECTS/CAUTIONS/CROSS DRUG/HERB INTERACTIONStions

Does the herb have any side effects, what cautions should be taken when using this medication?

Ideally, Psyllium should only be used after medical consultation. Patients are advised to avoid breathing in the dust from Psyllium powder when mixing, as this can cause allergic reactions when accidentally inhaled. Some of these reactions might include; difficulty breathing, stomach pain, difficulty swallowing, skin rash, itching, upset stomach and vomiting. Often times however, these side effects have largely been limited to employees working Psyllium manufacturing factories. Additionally, despite its association with reducing serum glucose levels in diabetics, people with diabetes who have difficulty regulating their blood sugar should not use Psyllium.

Does it interact with other herbs or pharmaceutical drugs?

Psyllium interacts with four main drug categories; Lithium, Mesalamine, Orlistat and Simvastatin. Whereas Psyllium interactions with Lithium medications may fluctuate between positive and negative depending on the specific constituents of the each Lithium medication, Psyllium generally interacts positively with the other three drug categories. Together, they generally amplify the effects, sought by taking Psyllium. STILL, PSYLLIUM SHOULD BE TAKEN ONLY AFTER CONSULTING WITH A PHYSICIAN OR PHARMACIST!!!

NOT-SO-FUN FACT: Psyllium in rare cases, has been known to cause anaphylactic allergic reactions, and in few cases death. This stresses the importance of taking the herb only after professional consultation.