Can Metformin help for prostate cancer?

Last week at the American Association for Cancer Research (AACR) meeting, Dr. Joshua and his team from Toronto presented the results of a small study they conducted with prostate cancer patients and the drug Metformin.

Details of the study:

  • 22 men with prostate cancer scheduled for prostate removal had been assigned up to 500 mg of metformin three times a day prior to their procedure.
  •  The median time on Metformin was 41 days
  •  Metformin significantly reduced fasting glucose, insulin growth factor-1, body mass index and waist-to-hip ratio – all parameters worth stabilizing for prostate cancer patients.
  • Also, and even more intriguing, Metformin reduced the growth rate of prostate cancer in some of the men


My take on this:


The result of this small phase II study is of absolutely of no surprise to me. As a naturopathic doctor who appreciates the powerful effects of nature to cure and heal, Metformin, also known, as Glucophage is one of those drugs I think can be really helpful when used appropriately.

FYI: Other trade names for Meformin include: Riomet, Fortamet, Glumetza, Obimet, Gluformin, Dianben, Diabex, and Diaformin.

Actually, the active chemical in metformin was originally derived from the plant goat’s rue (Galega officinalis). And guess what was this plants historical medicinal use? Give up?  Diabetes. 

Metformin is primarily prescribed for people battling Type II diabetes and obesity. Clinically, I’m impressed with its beneficial effects on weight loss.

How does Metformin work? Simply stated, it helps with sugar metabolism. In almost every dietary article I have written,  I have pointed out how sugar may be the absolute worse food for prostate cancer – even worse than red meat consumption. 

Sugar (and simple carbohydrates) is addictive and has a drug –like effect in the body. It contributes to weight gain, heart disease and all cancers including prostate cancer.  If not sugar itself that causes harm, it’s how your body responds to its over consumption by massively producing insulin and insulin like growth factors -1 (IGF-1).

The most common adverse effect for Metformin is lactic acidosis.

Actionable points:


  • If you would like to remain drug-free, exercising 4 to 6 times a week is a “must do” not a “want to.”  Weight resistance where you pull and push over your head, pull and push in front of your chest and squat up and down (as in getting up from your chair) should be done at least two times a week.
  • Try cross fit and tailor it to your fitness level. Don’t be intimidated. Just go for it – intelligently. If you are over 50 – get a stress test done first be a cardiologist. Here is a  CrossFit Beginners Guide. Again, get checked out by your doctor first if you have not been exercising much as of late. If possible, get a trainer – a good one is worth every penny.  Exercise has proven to control insulin and IGF-1 in patients with prostrate cancer. (Young-McCaughan , 2012)
  • Total abstinence from simple sugar consumption is impossible and not suggested. However mindful eating and significant reduction in consumption is. Breads, pasta, white flour, baked foods, table sugar are all culprits -  eat a quarter of what you are use to eating. Enjoy eating whole fruits (not fruit juice). Berries are best.
  • Although the Metformin study by Dr. Joshua and his team is compelling, it’s not conclusive. A randomized, placebo control trial would be of interest. However, if you are struggling with weight loss and have  (or have had) prostate cancer, Metformin may be a useful drug even if diabetes is not in the picture. Have a talk with your doctor about this. Not sure of its benefits if you’re in shape with or without a history of prostate cancer.


Bottom Line

There are no “silver bullets” to a cancer-free lifestyle and no magic pills – exercise, good nutritional habits, smart supplementation and the smart use of medical treatments (when appropriate) are ultimately the only way.


There’s still a couple of spaces left for the Prostate Cancer Health Retreat in May if you or someone you love has ever been diagnosed with this beatable disease. We’ll immerse ourselves in an anti-cancer lifestyle for two full days and learn how to continue an anti-cancer lifestyle at home.  Bring your humor with you – we are going to have a good time.

My social network friends will benefit from a 10% discount.

Let us know before Monday, April 16th if you would like to sign up as we are filling up.


CLICK HERE for more information.



Witters L. The blooming of the French lilac. J Clin Invest. 2001;108(8):1105–7.

Young-McCaughan S.Potential for prostate cancer prevention through physical activity. World J Urol. 2012 Apr;30(2):167-79

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