Insulin resistance and weight loss: does antagolin work?

Antagolin, an over-the-counter supplement that promises "to help alleviate insulin resistance and assist you gain better control over your weight" (MNI, 2013A), is being promoted everywhere in the media, including on TV. It is, therefore, understandable that the public are asking many questions about this product, such as "Is it safe?", "Will it help me lose weight/counteract insulin resistance or diabetes?", "Does it have side-effects?" and "Can I take it with my prescription medications?"

I set out to try and answer as many of these pertinent questions as possible, but was not able to obtain all the answers I was seeking. However, the public may find some of the results of my investigation insightful.

What does Antagolin contain?

The first step in trying to determine if an over-the-counter product is safe and effective without multiple serious side-effects, is always to check what the product contains. The comprehensive website and AntagolinTM package insert of the Medical Nutritional Institute (MNI) lists the composition of this product as follows:

Two tablets contain:
  • Insul-X2TM (Contains berberine) 30 mg
  • Banaba leaf extract 840 mg
  • Inositol 60 mg
  • Chromium 140 mg

a) Insul-X2TM

If we consider each of these ingredients, then it is immediately evident that the first compound Insul-X2TM poses a problem. Although the MNI lists the ingredient berberine as one component of this trade-marked compound, there is no disclosure of what else it may contain.

Berberine which is a chemical found in a number of plants such as European barberry and tree tumeric, has in the past mainly been used to treat heart failure and for its antibacterial properties (WebMD, 2013).

There is, however, some very recent research which has found that berberine can turn around the dysfunction of liver mitochondria (the power houses of the cell) in rats fed a high-fat diet (Teodoro et al, 2013). According to these authors, berberine is an "isoquinoline alkaloid with anti-diabetic properties".

Based on the results of the study with rats fed a high-fat diet, Teodoro and his co-authors (2013) conclude that, "berberine’s potent protective effects against metabolic syndrome may rely on increasing mitochondrial SirT3 activity, [and] normalizing mitochondrial function..."

Basically this is good news, but it is evident that a great deal of additional research will be required to prove that humans also react to berberine with improved mitochondrial efficiency which may or may not help with weight loss and/or help to control diabetes and insulin resistance.

It is very early for anyone to make the deduction that taking berberine in a dose of 30 mg twice a day will do what it is purported to do. In my personal capacity, I prefer to wait until more definitive research results are available from human studies.

Interaction with medicine

The second question regarding safety is addressed by the MNI Website which warns the public not to use the product during pregnancy and breastfeeding and in patients with liver disease. This is born out by the warnings that berberine may cross the placenta during pregnancy and harm the unborn baby. It is also excreted into breast milk and would thus be transferred to newborn and young children who can develop a condition called kernicterus which is a type of brain damage (WebMD, 2013)

The WebMB Website(2013) also warns that berberine interacts with medications called cyclosporins (which are used to treat organ rejection and in conditions like psoriasis, severe urticaria and so on), slowing down how the body breaks these down the cyclosporin which could cause toxicity.

This also applies to using berberine products together with any medications that are metabolised by the liver as it could increase the side-effects and/or make the effect of the medications more pronounced. Ask your doctor or pharmacist if you can use berberine extract with any medication that may be prescribed for you (e.g. Viagra is just one example).
b) Banaba leaf extract

Banaba leaf extract which is also called "Corosolic acid, Crepe Myrtle, or Pride-of-India", is derived from a species of "crepe myrtle tree" and is used for diabetes and weight loss. There is some indication that this extract can help lower blood sugar levels in type 2 diabetics and individuals with insulin resistance. Improving blood sugar levels could then lead to weight loss (WebMD, 2013)

However the research into this field is also in its very early stages and until large-scale well- controlled human trials have been completed, it is not possible to substantiate any of these claims.

Warnings about the use of Banaba leaf extract also include prohibition of its use during pregnancy and breastfeeding (WebMD, 2013) and cautions that because it may have the potential to lower blood sugar levels, patients who use Antagolin together with other diabetic medications (such as glucophage, insulin, etc), may experience additive effects which can cause hypoglycaemic episodes.

Keep in mind that if you are taking any diabetic medications that you must discuss the use of other products that you can buy without a prescription with the medical doctor who is monitoring your diabetes. The MNI Website and the Antagolin package insert also emphasise this.

It stands to reason that if you are lowering your blood sugar levels with a prescribed medication such as Glucophage or insulin, and you take another product such as Banaba leaf extract which also has the potential to lower your blood glucose, that you can end up with blood glucose levels that have been lowered too much and develop a hypoglycaemic coma.

Patients using Banaba leaf extract are also warned not to use the product for at least 2 weeks before surgery because it is potentially dangerous to interfere with blood sugar levels before and after surgery.

c) Inositol

Inositol was identified as a potential aid in controlling insulin resistance, metabolic syndrome and weight loss as early as 2011 when the first definitive papers were published on this nutrient. It, therefore, appears sensible to include inositol in a preparation like Antagolin which is intended to promote weight loss and control insulin resistance.

d) Chromium

The MNI Website (2013) states that Antagolin contains 140 microgram of chromium in a dose of 2 tablets and that patients should use 2 doses a day, which would result in them ingesting 240 microgram per day.

According to the European Safety Authority (Aguilar et al, 2008), chromium compounds, like any heavy metal, have the potential to be toxic if ingested in large quantities. The form in which they are ingested is also important in relation to chromium supplements.

There is at present no Safe Upper Limit determined for chromium, but the UK Expert group on Vitamins and Minerals (EVM) have concluded that an intake of 0,15 mg of trivalent chromium/kg body weight/ day or 10 mg per person per day would not cause negative health effects (Aguilar et al, 2008).

The WHO has suggested that chromium supplementation should not exceed 250 microgram per day in humans.

The EVM of the UK has advised the public that chromium picolinate should rather not be used and that other forms of trivalent chromium such as chromium polynicotinate may be safer.

It would be informative if the NMI Website and the AntagolinTM package insert (MNI, 2013A & B) would specify which form of chromium is used in AntagolinTM.


In general it would appear that Antagolin may be able to assist patients with insulin resistance to lower their blood glucose levels and thus if combined with a sensible low-fat, low-GI diet and exercise to also promote weight loss.

However, until a great deal more research is carried out on the various components of Antagolin, including those that may possibly be contained in the Insul-X2TM component and are not listed, it is not possible to recommend that patients with insulin resistance and/or type 2 diabetes should use this type of over-the-counter medication.

It is safer and more prudent to consult a medical doctor and a registered dietitian to assist you with weight loss and to stabilise your blood sugar levels.
(References: Aguilar F et al, 2008. Scientific Opinion. Mixture of chromium di- and tri-nicotinate as a source of chromium added for nutritional purposes in food supplements and in foods for particular nutritional uses.  The EFSA Journal, 887, 1-24; Medical Nutritional Institute (2013A) Antagolin. ; Medical Nutritional Institute (2013B) Antagolin Package Insert; Teodoro J S et al (2013). Berberine reverts hepatic mitochondrial dysfunction in high-fat fed rats: A possible role for SirT3 activation. Mitochondrion, 13(6):637-646; WebMD (2013) Find a vitamin or supplement. Banaba /Berberine.

(Photo of woman measuring her waist from Shutterstock)

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