Sugar in the brain isn’t so sweet

Do you like your brain? Do you think you like your brain? If you think you like your brain, and your brain is responsible for your thinking, is you liking your brain really just your brain liking itself? If “I think, therefore I am,” as Rene Descartes one said, then am I because of my brain?

Wikimedia Commons/Public Domain (Author: Jason Hise, 2007)

OK, I’ve either emptied your metaphorical cup of tea, thus you’re ready to dive into some science, or I’ve just confused you senseless, in which please wipe the drool from your chin because we’re about to dive into some science. Either way, we’re going to be talking about the brain and some disconcerting studies about the negative effects of sugar.

First, a little bit of brain anatomy: ‘glial cells‘.The glia have several functions that support the neurons; without the glia, neurons just won’t work all that well. In fact, when they go wrong, they’re often associated with really nasty diseases, particularly multiple sclerosis (MS). Think about it: how good is electrical wire when it’s not insulated? You get zapped, the wire is easily frayed, and easily breakable. Same thing with neurons, and the glia keep it essentially together.

Wikimedia Commons, CC-BY-SA-40 International (Author: BruceBlaus, 2017)

But like a lot of cells in the body, glia can get tumors as well (glioma), which may lead to cancer. What makes this also interesting (and bad) is that according to the researchers’ literature review of the present study (it’s open, so there’s no paywall and feel free to download it), while there seems to be mixed results regarding the relationship between the presence of tumors, some studies have found that the risk of malignant (cancerous) tumors may be increased in people diagnosed with diabetes. This may be a huge concern, particularly in the United States where diabetes diagnoses have been increasing since 1958. Of course, that’s not to say that this isn’t a global problem, so no snarking off on other countries, OK? Play nice in the comments below.

Back to the science – tumor cells are not zombies or anything, OK? They’re not the living dead, they’re very much alive. Very, very alive – they’re essentially cells that will grow out of control and may not even die. So, it’s more like kudzu. Anyway, because tumor cells are hyperactive and out of control, one would expect that they require a lot of energy. They do – the literature review (no one does any research without doing a lot of reading – believe me) talks about the Warburg effect, which in short is that tumor cells (especially malignant ones – that would be cancer) require more glucose than normal cells. They also cited studies that link blood glucose to cancer growth and risk, although high blood glucose is linked to all sorts of things anyway, which they did recognize.

This study was correlational – they didn’t test human subjects themselves, instead they used data from two very large studies on cancer with total sample size of close to a million people. This is typical for biostatistics research, really. So what relationships did they find? They found that there was an inverse relationship between blood glucose levels and glioma risk as well as blood glucose levels and actual glioma. What does this mean? Low blood glucose means that a lot of it is being consumed for some reason, and it’s likely (nothing for sure, though) that it’s being taken up by the cancer cells – this confirms what previous studies have found. The authors do warn that there are other variables that they can’t consider since they don’t have the info, such as BMI, blood pressure, and so on. These are important since they “are associated with both diabetes and glioma,” so whoever wants to take up this research should really look into this.

So where does diabetes kick in? Yes, they mentioned that diabetes is a risk factor for most types of cancer. But doesn’t diabetes raise blood glucose levels, since the body isn’t able to use it? That’s right – diabetes may actually lower the risk of glioma.

Public Domain (Author: Clker-Free-Vector-Images, 2014)

Aaaaand this is why there’s a need to do more research and gather more data – this is the kind of information that can be easily mixed up without a deeper understanding of how body systems affected by diabetes (and hyperglycemia – literally, too much sugar) interact with body systems affected by cancer, which in this case will be glial cells in the brain. Does this mean cut off sugar completely from your diet? For lack of a better answer, we may as well go with moderation for now.

Yeah, coming from a guy whose blood type is ‘dark roast’.

Public Domain (Author: Ivan Ilijas, 2015)

Serious note: if you’re thinking of dietary changes due to a history of cancer (or really any kind of medical condition) in your family, yes see your doctor, but you should also talk to a registered dietitian.

Featured Article: Schwartzbaum J, Edlinger M, Zigmont V, Stattin P, Rempala GA, Nagel G, Hammar N, Ulmer H, Föger B, Walldius G, Manjer J, Halmström H, Feychting M (2017). Associations between prediagnostic blood glucose levels, diabetes, and glioma. Scientific Reports 7: 1436. DOI: 10.1038/s41590-017-01553-2

Featured Image: Public Domain (Author: 422737, 2014)


    1. I would strongly recommend not injecting anything into your skull – sugar, painkillers, darts, ANYTHING!!!

      And yeah, diabetes isn’t worth the trade. Remember, correlation is not causation, so diabetes may not definitively stop or even prevent glioma. Not to mention the host of other not good things that happens when one has diabetes.

      Liked by 1 person

  1. Interesting, I do a lot of work with diabetes (have my first article accepted for publication woohoo, but those lit reviews tho… :), and I like your down to earth but hold your attention writing. I’ll be back for more!

    Liked by 1 person

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s