What is a Glucose Ketone Index and Why You Should Care

Having high levels of ketones doesn’t mean you’re automatically getting all of the benefits. Luckily, research shows us that there’s an easy way to know if you’re in prime therapeutic mode so you can be confident you’re getting the best results. 

Ketosis can already be complicated if you don’t test and figure out what kicks you out. Once you start getting serious about ketosis and tracking ketone levels, you can usually step things up a notch with a simple calculation. You can become more specific with what works for you as an individual. How you do that is by calculating your glucose ketone index.

The Glucose Ketone Index, or the GKI, is a ratio that researcher Dr. Thomas Seyfried has been using in his studies relating to both fasting and the ketogenic diet. There’s nothing fancy to this index, it is just a ratio of blood glucose levels to blood ketone levels.

Having high level of ketones are great and all, but if you also have a super high level of blood glucose, you’re really just spinning your wheels and not getting any benefits of ketosis. And the real key here is to make sure that the ratio between glucose and ketone levels is as low as possible.

If you’ve been following along, you’ll note I was pretty big on this glucose ketone index on my recent my four day fast and it actually dictated the time spent in the fast. But why did I care about this ratio, and why should you care?

Why Should You Care?

Dr. Seyfried does a lot of his research in the realm of cancer treatment and has noticed increasingly impressive therapeutic outcomes with the lower the glucose ketone index ratio gets. Dr. Seyfried claims that a GKI of lower than 1.0 is prime therapy for patients with cancer, and he has plenty of data to back this up. 

The graph above shows how tumor growth in his research is very clearly managed under a GKI of 1.0.

Some other examples from a publication of his research findings:
22% reduction in tumor metabolism going from 27.5 to 1.1 GKI for 56 days
88% reduction in tumor dry weight going from 15.2 to 3.7 GKI for 13 days
5x (!!!) survival time (41 days vs 200+ days) when combining radiation treatment and lowering from 32.3 to 5.7 GKI for only 13 days

This make a whole lot of sense when you think about it. Cancer cells survive on glucose. The more ketones and less glucose, the more they starve and the more they die.

The glucose ketone index isn’t just for cancer treatment. This value is also of importance for people who have blood sugar issues. The GKI also isn’t just for ketosis. This is a way you can measure how effective the results of fasting are. 

If you’ve had a history of diabetes, obesity, or other metabolic problems, you should definitely be tracking this index and try to get it as low as possible.

Lower blood sugar also comes with decreased inflammation, increased longevity, improved energy, and more rapid fat loss. All nice things, right?

Ok, so the lower GKI, generally the better.

how to measure your glucose ketone index

How To Measure Your Glucose Ketone Index

How do you calculate the glucose ketone index value yourself? Pretty easy.

Equipment needed:
– A glucose meter with strips
– A ketone meter with strips
– A calculator (or your brain)

Step One:

Take your glucose reading. If you’re in the good ol’ US of A, you’ll get a reading in mg/DL. Which, just like many things in this country, is completely different from how the rest of the world measures this value. For no reason.

If you’re measuring in mmol, you’ll be able to skip a step later.

Note this number.

Step Two:

Take your ketone levels. This should be with a blood meter and the reading should be in mmol. If you don’t know how to test your ketone levels click that link I inserted to learn how.

Note this number.

Step Three:

Take the number you got in step one (your glucose in mg/dL) and divide that by 18. Now divide this number by the number from your ketone meter in step two.

BAM! There is your own, personal, glucose ketone index!

I’ve been in pretty deep ketosis for awhile and while I can sometimes sneak my glucose ketone index below 1.0, I have to estimate it’s pretty tough to stay in that range for long when eating.

Your ketones simply don’t get high enough and your blood sugar doesn’t stay low enough for long enough.

If you are already tracking your ketone levels and not calculating this measurement of glucose ketone index, please go spend the extra few bucks on a glucose meter and some strips and do some quick calculations to see where you’re at to get a larger picture of your metabolism and health as a whole.

Now please can someone come up with an app or piece of hardware that does all of this automatically and graphs it so I don’t have to start another company? Thanks 🙂

Bonus: If you want to effortlessly calculate your GKI and a ton of other markers, head to Heads Up Health to aggregate everything in an awesome dashboard. No affiliation, just a great program.