Cancer Risks from Insulin

The buzz on the Internet this weekend  is the news that insulin glargine (Lantus) might increase cancer rates. Needless to say, this is very upsetting news to a lot of people, although Lantus has been linked with cancer in the past.

Dr. Bill Quick has provided a good overview of the situation, with links to the original papers, which are available free, full text.

I'd like to add a few other comments.

In the editorial accompanying the articles, the authors conclude:

1. "There is no evidence that insulin, however formulated, causes cancer."

2. But "the growth of some tumor cells lines is clearly enhanced by insulin."

3. "Circulating levels of endogenous insulin appear to be associated with cancer risk in obesity and other insulin-resistant conditions, including type 2 diabetes."

4. "There is no evidence of harm in type 1 diabetes, or in males, or in premenopausal breast cancer."

5. "On current evidence, the short-acting analogues do not appear to present a potential problem."

In other words, there is evidence that very high levels of insulin, no matter what the source, may increase the growth of pre-existing cancers. People with insulin resistance (metabolic syndrome or type 2 diabetes) are at increased risk whether or not they inject insulin of any kind.

Hence, for us, the best approach would be to do whatever we can to reduce the amount of insulin that we need. Reducing insulin resistance through exercise and, if possible, weight loss should help.

Another approach, available to everyone regardless of ability to exercise or lose weight, is to reduce the amount of carbohydrate you eat.

The less carbohydrate you eat, the less insulin you need. The less insulin you need (either your own or injected), the lower your risks of encouraging the growth of cancer cells. It seems fairly easy to understand.

But some people just don't seem to get it. How long will it be before the American Diabetes Association stops telling people with type 2 diabetes to eat more carbohydrate and "Make starch the star"?

For a more detailed report of these studies, see here.