Complicated French Study Explains How A Low-Carb Diet Can Prevent Seizures
Posted Sep 11 2008 8:27pm
I'll be the first to admit to you that sometimes the medical jargon that accompanies some of these low-carb studies that come out absolutely baffle the heck out of me. Sure, many of them are straightforward enough for me to get the gist of them so I can blog about what you need to know about them. But sometimes...
The good news is I have LOTS of friends in high places of learning and experience who are much more adept at understanding the lingo enough to make it palatable to us common folk. So, for this one, I looked no further than the author of The Brain Trust Program himself, neurosurgeon Dr. Larry McCleary, for his assistance with translating what this study means. As expected, Dr. McCleary did not disappoint.
Let me warn you that this can be a bit difficult to follow despite the fact it is written in as simplistic language as possible. But Dr. McCleary even admitted to me that "the chemistry is a bit complicated." Even still, I think you'll enjoy reading his wrap-up about this French study from lead researcher Joseph Vamecq1 and his fellow researchers. I've included links to Wikipedia for terms you may not be familiar with.
Here's how Dr. McCleary summarized the study:
This is an article that talks about the interactions between astrocytes and neurons in the context of seizure control and prevention as modulated by conversion of the "normal" high-carb diet to a ketogenic (high fat, low-carb) diet. They focus on several metabolic shuttles between neurons and astrocytes as the sites of this dietary impact.
Normal high carb diet
The brain uses glucose as follows. Astrocytes take up glucose, metabolize it to lactate and then transfer it to neurons where it is further oxidized to acetyl CoA which enters the Krebs Cycle where it is further metabolized and NADH, CO2 and H2O are produced.
On a ketogenic diet there are higher concentrations of fatty acids and ketone bodies in the bloodstream with lower levels of glucose. In addition, astrocytes have the ability to act like liver cells in the sense that they too can partially oxidize fatty acids into ketones. The ketones are then transferred to the neurons where they are burned as a source of fuel.
Hence on a ketogenic diet two things happen in neurons:
1. More ketones are burned. 2. Less glucose is burned.
This induces several specific changes. The first is that with the change from glucose (in the form of lactate) to ketones as the fuel source, more oxaloacetate is consumed. Oxaloacetate is a metabolic intermediary in the Krebs Cycle. When this happens more glutamate is produced in neurons which is subsequently consumed by its metabolism into the inhibitory neurotransmitter GABA (gamma amino butyric acid).
Glutamate is an excitatory neurotransmitter. The ratio of glutamate/GABA is important for seizure control. High ratios favor seizure production. Low ratios favor seizure inhibition.
The ketogenic diet produces lower levels of glutamate and higher levels of GABA. This lowers the ratio and acts to prevent seizures.
Globally speaking, the ketogenic diet, by limiting brain glycolysis (metabolism of glucose) and increasing its dependence on fat (ketone bodies), produces a beneficial change in the ratio of glutamate/GABA that favors less excitation and hence better seizure protection.
Is your head spinning as much as mine? Be glad this is the EASY version of the original study! A BIG "Livin' La Vida Low-Carb" blog THANKS to Dr. Larry McCleary for explaining this study confirming low-carb diets are an excellent way to decrease or even eliminate the occurrence of seizures. There's no way I could have ever figured out what this study meant without you, Dr. McCleary! :)
You can e-mail Joseph Vamecq about his study (although I'm not sure he could explain his study any clearer than Dr. McCleary did) at firstname.lastname@example.org.