Herbs for Diabetes

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Bitter Melon

Bitter melon has also long been used as a herbal remedy for a range of ailments, including type 2 diabetes.

The fruit contains at least three active substances with anti-diabetic properties, including charantin, which has been confirmed to have a blood glucose-lowering effect, vicine and an insulin-like compound known as polypeptide-p.

These substances either work individually or together to help reduce blood sugar levels.

It is also known that bitter melon contains a lectin that reduces blood glucose concentrations by acting on peripheral tissues and suppressing appetite - similar to the effects of insulin in the brain.

This lectin is thought to be a major factor behind the hypoglycemic effect that develops after eating bitter melon.

Scientific evidence

A number of clinical studies have been conducted to evaluate the efficacy of bitter melon in the treatment of diabetes.

In January 2011, the results of a four-week clinical trial were published in the Journal of Ethnopharmacology, which showed that a 2,000 mg daily dose of bitter melon significantly reduced  blood glucose levels among patients with type 2 diabetes, although the hypoglycemic effect was less than a 1,000 mg/day dose of metformin. [68]

Other older studies have also suggested an association between bitter melon intake and improved glycemic control, while a report published in the March 2008 issue of Chemistry and Biology found that bitter melon increased cellular uptake of glucose and improved glucose tolerance. [69]

However, research published in the Journal of Clinical Epidemiology in 2007 failed to show any benefits of bitter melon for poorly controlled type 2 diabetes, while another clinical review published two years later in the British Journal of Nutrition stated that more, better-designed and clinical trials are required to confirm the fruit’s role in diabetes treatment. [70]

http://www.diabetes.co.uk/natural-therapies/bitter-melon.html

[69] - British Journal of Nutrition; Anti-Diabetic and Hypoglycaemic Effects of Momordica Charantia (Bitter Melon): A Mini Review; L. Leung; December 2009
[70] - Journal of Clinical Epidemiology; The Effect of Momordica Charantia Capsule Preparation on Glycemic Control in Type 2 Diabetes Mellitus Needs Further Studies; A.M. Dans, et al.; June 2007




Cinnamon

This study demonstrates effects of low levels (1–6 g per day) of cinnamon on the reduction of glucose, triglyceride, LDL cholesterol, and total cholesterol levels in subjects with type 2 diabetes. The study design serves to replicate the results because there were similar effects at the three doses tested. It is not clear whether even less than 1 g of cinnamon per day would also be beneficial. The data are also reinforced by the observation that there were no significant changes in any of the placebo groups. There were also no problems with compliance or problems associated with the consumption of ≤6 g of cinnamon per day.

The mechanism of the effects of cinnamon on glucose and blood lipids must be determined. Symptoms of insulin resistance include decreased stimulation of muscle glycogen synthesis as well as defects in glycogen synthase activity and glucose uptake (18). In addition, altered enzymatic activities, such as an increased phosphatase activity and/or seryl phosphorylation of the insulin receptor substrate by glycogen synthase kinase-3 (GSK-3), have also been shown to be involved in some cases of type 2 diabetes (19,20). Dephosphorylation of the receptor β-subunit is associated with the deactivation of its kinase activity and, therefore, is associated with insulin signal downregulation (21). Maximal phosphorylation of the insulin receptor is associated with increased insulin sensitivity, which is associated with improved glucose and lipid levels. Extracts of cinnamon activated glycogen synthase, increased glucose uptake, and inhibited glycogen synthase kinase-3β(11,12). Extracts of cinnamon also activated insulin receptor kinase and inhibited dephosphorylation of the insulin receptor, leading to maximal phosphorylation of the insulin receptor (12). All of these effects would lead to increased insulin sensitivity. We have shown that extracts of cinnamon also function as potent antioxidants, which would lead to additional health benefits of this substance (unpublished data). Dhuley (22) showed that cinnamon displays antioxidant activity in rats fed a high-fat diet.

http://care.diabetesjournals.org/content/26/12/3215.full




Fenugreek

Fenugreek seeds (trigonella foenum graecum) are high in soluble fibre, which helps lower blood sugar by slowing down digestion and absorption of carbohydrates. This suggests they may be effective in treating people with diabetes.

Multiple studies have been carried out to investigate the potential anti-diabetic benefits of fenugreek.

Of these, several clinical trials showed that fenugreek seeds can improve most metabolic symptoms associated with both type 1 and type 2 diabetes in humans by lowering blood glucose levels and improving glucose tolerance.

In one study, researchers in India found that adding 100 grams of defatted fenugreek seed powder to the daily diet of patients with insulin-dependent (type 1) diabetes significantly reduced their fasting blood glucose levels, improved glucose tolerance and also lowered total cholesterol, LDL or ‘bad’ cholesterol and triglycerides.

In another controlled trial, incorporating 15 grams of powdered fenugreek seed into a meal eaten by people with type 2 diabetes reduced the rise in post-meal blood glucose, while a separate study found that taking 2.5 grams of fenugreek twice a day for three months lowered blood sugar levels in people with mild, but not severe, type 2 diabetes.

http://www.diabetes.co.uk/natural-therapies/fenugreek.html




Gymnema

The leaves of the Gymnema sylvestre plant contain gymnemic acids, which have been shown to slow the transport of glucose from the intestines to the bloodstream. This, in turn, helps to:

Lower blood sugar
Lower hemoglobin A1c
Some research also suggests that gymnema sylvestre extract can help repair and regenerate the beta cells in the pancreas that produce insulin.

Research has shown that Gymnema sylvestre extract is an effective therapy for both type 1 and type 2 diabetes.

In one clinical trial, 22 people with type 2 diabetes who were taking oral diabetes drugs also took 400 mg of Gymnema sylvestre extract (as GS4) daily. Participants experienced significant reductions in blood sugar, hemoglobin A1c and glycosolated plasma protein levels.

More remarkably, at the end of the 18-month study, the participants were able to reduce their drug dosages, and five of the study subjects were able to effectively maintain normal blood sugar levels with the GS4 alone. The researchers concluded, “the beta cells may be regenerated in type 2 diabetic patients on GS4 (Gymnema sylvestre) supplementation.”

In another study, researchers gave 27 people with type 1 (insulin-dependent) diabetes 400 mg of Gymnema sylvestre extract (GS4) daily. After 10 to 12 months, Gymnema sylvestre extract conferred a number of benefits, including reductions in fasting blood sugar, hemoglobin A1c and glycosylated plasma protein levels. Insulin requirements were also reduced.

http://www.ncbi.nlm.nih.gov/pubmed/2259216
http://www.drwhitaker.com/the-benefits-of-gymnema-sylvestre-extract/




Onion

Anti-diabetic properties of red onion

Researchers from the department of pharmacology at the University of Gezira published the results of a preliminary study on the anti-diabetic properties of red onion (allium cepa) in the journal, Environmental Health Insights [1].  The purpose of their study was to investigate the hypoglycemic properties of red onion in patients with Type 1 and Type 2 diabetes.

The study itself included two groups of 21 patients each consisted of patients with either type 1 diabetes (group 1) or type 2 diabetes (group 2).  The patients included in this study were under the age of 50, not taking medicine for other health conditions, and did not smoke or consume alcohol.  The participants were given 100 g of red onion either while fasting or following an oral glucose tolerance test.

Type 1 diabetes results:

Fasting blood glucose was lowered by 145 mg/dl in response to administration of insulin (4 hours later).  In comparison, 100 g of allium cepa (red onion) resulted in a 89 mg/dl reduction in fasting blood glucose levels (4 hours later).

Next, this group participated in an oral glucose tolerance test (GTT) in which they were administered 75g of dextrose.  Insulin administration lowered their blood sugar by 152 mg/dl (4 hours later) while allium cepa resulted in a reduction of their blood sugar by 120 mg/dl.  Water alone was also used as a comparison and it resulted in a 77 mg/dl reduction in blood sugar levels fours hours after the dextrose challenge.

Type 2 diabetes results:

For fasting blood glucose levels, 100 g of crude red onion resulted in a 40 mg/dl reduction in blood glucose levels, four hours later.  In comparison, administration of 5 mg of the diabetes drug, glibenclamide, resulted in a reduction of 80 mg/dl.

Following the induced hyperglycemia (GTT), 100 g of allium cepa resulted in a 159 mg/dl reduction in blood glucose levels compared to water 55 mg/dl and glibenclamide 114 mg/dl.

Study conclusions:

The study authors succinctly concluded the following:

“Allium cepa in addition to its nutritional values has hypoglycemic effects that could be beneficial in management of type 1 and type 2 diabetic patients of all age groups, especially the level of its safety as reflected by its worldwide use as vegetable.”
Another interesting point made by the study authors was that they observed an increase in blood glucose levels after the first hour following allium cepa administration which they attributed to the glucogenic effects of Allium cepa.  The study authors noted that this could counteract the common side effect, hypoglycemia of many anti-diabetic agents.

http://jarretmorrow.com/2010/11/24/onion-blood-sugar-levels-diabetics/




Turmeric

Although no long-term studies have been done specifically in people with diabetes, the bench research shows that turmeric does reduce many of the inflammatory signals known to be overactive in diabetes (i.e. cytokines IL-6, IL-1, and TNF) and improves the action of disrupted insulin-response pathways in diabetes (i.e. PPAR-gamma) (Shishodia et al. 2005)!

http://www.diabetesaction.org/site/PageServer?pagename=complementary_july_06