This week, the British Journal of Cancer published an incredibly important report that found a strong relationship between a simple blood test and the risk for various forms of cancer. The study found that the common blood test used by diabetics to measure their average blood sugar, A1c, was strongly predictive in terms of cancer development.

For those of you who are not diabetic, you may not be familiar with this simple test that has profound health implications well beyond diabetes. Basically, the A1c test measures the amount of glycation that the protein hemoglobin has undergone. Glycation simply means that sugar has become bonded to a protein, in this case hemoglobin, and this is a relatively slow process. Hence, it’s a way to get a sense as to how high the blood sugar has been, in this case over a 3-4 month period of time, and this is why it’s so helpful for diabetics.

But with this new report, we now understand that having elevated A1c translates to risk for cancer, and as I’ve explained in Grain Brain, it is also a powerful indicator of risk for developing dementia. If you look at the chart on page 117 of the book, reproduced below, you’ll note that A1c is also directly related to the rate at which the brain shrinks on an annual basis.

Think of it, this one simple blood test can give you incredibly important information about cancer risk, risk for dementia, and even risk for shrinkage of your brain!

Most commonly people are told that having an A1c of 5.6 – 5.8 should be considered normal, but when you look at the graph above, these levels already put you in the second highest category for brain shrinkage! I believe that, based on this information, we should strive to keep our A1c at 5.2 or even lower. The way to accomplish this is simply by reducing your consumption of carbohydrates and sugar. Who knew!

Why the process of glycation is such a bad player for health likely stems from the fact that when proteins are glycated (bound to sugar), it dramatically increases the production of damaging chemicals called free radicals. Free radicals end up damaging our protein, fat and even our DNA. In addition, glycation of proteins dramatically increases the chemical mediators of inflammation, and inflammation is the pivotal player in so many issues including diabetes, heart disease, cancer, Parkinson’s, Alzheimer’s, multiple sclerosis, asthma and arthritis, just to name a few.

Beyond keeping your carbs low, there are several “anti-glycating” supplements that are helpful to reduce this process. These include alpha-lipoic acid, the omega-3 DHA, and a form of thiamine called benfotiamine.