Could This Drug Actually Help You Live Longer?

Scott: Doctor Grossman, you're talking about metformin here at the conference.  Could you explain what that is? I mean I think a lot of people know it as a diabetes drug, but are there other uses?

Dr. Terry Grossman: Yeah.  Metformin is an FDA approved drug for the treatment of type 2 diabetes.  The type of diabetics that don't need insulin, typically.  And it's the most commonly prescribed drug of it's class, with millions and millions of prescriptions written every year, because it's very effective and safe.  It's the only diabetes drug that doesn't increase cardiovascular risk, it's got a lot of beneficial effects. 

Well, there are some off-label uses that have been proposed for metformin, and in particular, the only method that has been shown so far to increase life expectancy, in all of the animal experiments that have been done, is caloric restriction.  The problem is caloric restriction is very difficult.  People don't want to do it, because... in animal experiments will cut the calories by about 35 percent and there are some humans that have done this.  The problem is they tend to be very, very thin, they're hungry all the time.  And even the animals, in these animal experiments, like when they do the experiments with the rats and the mice, they have to put them in separate cages, otherwise they'll eat on another, because they're literally starving.  So no one wants to do that.  Very few people are willing to subject themselves to that degree of caloric restriction in order to gain some additional years of life, theoretically. 

The way that caloric restriction seems to work, at it's basic level, is by reducing the effect and the levels of insulin in the body.  And it also slows down metabolism.  Metformin also reduces insulin levels in the body, and increases it's effectiveness.  So there have been some early studies that suggest that just taking metformin, which is inexpensive, associated with relatively few side effects, doesn't cause low blood sugar and things, may have some of the benefits of caloric restriction.  So, I've started to take it myself, personally.  And I've put a number of my patients on it and no one's had any side effects.  The problem is we don't know for sure that this will translate into increased longevity, but we do know that metformin has a number of other beneficial effects.  In particular, in many studies, it's been shown to reduce the incidents of cancer.  And, for instance, diabetics are at an increased risk for cancer.  One of the reasons being that cancer cells love to eat sugar.  Diabetics tend to have higher blood sugar levels all the time.  So they're at a high risk of several types of cancer.  The diabetics that take metformin have a much lower chance of developing cancer than diabetics that are treated with other medications.  So there are a lot of reasons that I think it's worth taking a look at metformin, even for healthy, non-diabetics.  

Scott: Doctor, you said that you take metformin, and have some patients on it with no side effects.  Are there possible effects to that drug?

Grossman:  Metformin, if you look at the listing of the possible side effects, most of them are related to gastrointestinal.  And the first time that I took it, about 50 percent of people may develop diarrhea.  And to be perfectly honest, I just stated taking the full dose right from the beginning, and I got that side effect myself.  So, what I did was I started at a very low dose.  And by starting at a low dose and working up gradually, I found that I was able to take it without any problems at all.  And I do the same thing with my patients.  I just start at a low dose and go up.  But other than the, other than the gastrointestinal effects, there are very few side effects associated with it.  There are some contra-indications, such as patients with kidney failure and heart failure and things, that need to watch out, but for healthy people in general, there are minimal side effects.