Metformin and Cancer

Gretchen Becker Health Guide
  • Many people see prescription drugs as a last resort. And there's some basis for this caution: most drugs have side effects, ranging from annoying to fatal.


    However, not treating diseases also has side effects ranging from annoying to fatal. For example, we know that high blood glucose levels have serious side effects. So we always have to weigh the risks of a drug vs its benefits to determine whether we should or should not take that drug.


    Hence it's rather refreshing to see a story reporting that the common diabetes drug metformin may help fight against cancer. (The full text of the story is available here.)

    Add This Infographic to Your Website or Blog With This Code:


    According to this study, metformin seems to help kill breast cancer stem cells, the ones that produce more cancer cells and are difficult to eradicate with chemotherapy alone. In this study, although pretreatment with metformin reduced the incidence of tumors, the metformin alone didn't kill the cells once the tumors had grown. But it had a dramatic effect when given along with doxorubicin, a standard chemotherapy drug.


    The study was done in cancer cells in culture and in mice. And we know that in vitro  (test tube) and mouse studies don't always translate into in vivo (in the whole body) human results.


    Still, this study is consistent with other studies suggesting that people taking metformin have lower cancer cancer rates than those who do not take the drug. And it's important, because people with diabetes tend to have higher cancer rates in general. Because metformin is now available in a relatively inexpensive generic form, there is less incentive for pharmaceutical companies to try to tweak these results in their favor.


    It's encouraging to know that sometimes a side effect of a prescription drug can be beneficial. Does this mean that we should put metformin in the drinking water to try to lower cancer rates in everyone?


    Clearly, no. Even though the side effects of metformin seem to be mostly annoying (gastrointestinal) or positive, who knows what side effects they'll discover in the future. In 10 years they might discover that metformin reduces cancer rates and increases the rates of some other deadly disease.


    In deciding whether or not to take metformin or any other prescription drug, we have to remember that nonprescription drugs, foods, sedentary lifestyles, stress, polluted air and water, smoking, and myriad other factors can also harm us. Many people think of aspirin and acetaminophen as harmless drugs, but they too can have serious, sometimes fatal, side effects. 


    So can eating too many empty calories every day.



Published On: September 16, 2009