You may have stumbled upon the term Glucose Ketone Index (GKI) in various keto forums, social media, or even some research studies and wondered, what exactly is GKI? Why is it important? How to calculate it? What does the result mean? Read on to find your answers.
What is the Glucose Ketone Index (GKI)?
The Glucose Ketone Index was originally conceived by Dr. Thomas Seyfried and his team at Boston College to track the overall metabolic health of cancer patients. It was quickly adopted as a benchmark for those with other metabolic diseases and for anyone who wants to maintain their metabolic health.
Your GKI is the ratio of your blood glucose to your blood ketones at any given point in time.
It’s also useful to track blood glucose or blood ketones separately, but this ratio provides additional insight and a quick benchmark for people who are pursuing therapeutic ketosis.
The results show a clear relationship between the GKI and efficacy using a ketogenic diet and calorie restriction. The GKI is a simple tool to help monitor the efficacy of metabolic therapies for malignant brain cancer and other cancers that may express aerobic fermentation in preclinical animal models and clinical trials.
Why is GKI Important to You?
On their own, glucose or ketone readings give you a snapshot of where you are at that exact moment, meaning they can be independently influenced by direct variables such as stress (which raises blood glucose) or fat-rich meals (which raise ketone bodies).The GKI gives you a better overall picture of your metabolic state and ketosis status because its calculations take into account a variety of variables, thus normalizing them and thus have a more accurate and stable picture of your status.
So, once you know your GKI, you can use it as a tool to help track your ketosis and general metabolic status. It is also becoming an increasingly important measure of therapeutic ketosis in the medical industry for managing chronic health conditions, including certain types of cancer, type 2 diabetes, obesity, Alzheimer’s disease, Parkinson’s disease, chronic inflammatory diseases, epilepsy, insulin resistance and traumatic brain injury.
How to Calculate Your GKI?
GKI is blood glucose (mmol/L) divided by blood ketones [BHB] (mmol/L). If you are in the US, it is blood glucose (mg/dL) divided by 18 divided by blood ketones [BHB] (mmol/L). That is, (glucose reading (mg/dL) ÷ 18) ÷ ketone reading (mmol/L) = glucose ketone index.
First, you will need a glucose meter and a blood ketone meter. Blood glucose meters are easy to find at any pharmacy, and their test strips are usually inexpensive, as low as $0.30 each. You may need to purchase a ketone meter online, and these test strips are usually around $2.00 each.
Getting a reading involves pricking your finger with the lancet provided and waiting 5-10 seconds for the results. Plugging these numbers into the formula will give you your GKI.
How to Interpret the Results?
| GKI | What it means | Application |
| ≤1 | You’re in the highest therapeutic level of ketosis. | Very Difficult to achieve without doctor’s supervision. |
| 1-3 | You’re in the high therapeutic level of ketosis. | For those using keto therapeutically for the treatment of diseases such as cancer, epilepsy, Alzheimer’s disease, Parkinson’s disease, traumatic brain injury and chronic inflammatory disease. |
| 3-6 | You’re in a moderate level of ketosis. | For those with Type 2 diabetes and obesity, insulin resistance, metabolic or endocrine disorders. |
| 6-9 | You’re in a low level of ketosis. | Ideal for weight loss and health maintenance. |
| ≥9 | You are not in ketosis. | N/A |
When and how often should I test my GKI?
Blood glucose and ketone testing should be done 2 to 3 hours after a meal ( after a meal), twice a day if possible. Testing twice a day will allow you to recognize if and how your dietary intake is affecting your GKI.
How can I Lower my GKI Reading?
The longer you live a clean ketogenic lifestyle on a whole food-rich diet, the better your GKI readings will be. You can also influence your numbers by intermittent fasting, reducing stress and getting enough sleep (stress and exhaustion can trigger your body to release cortisol, which can spike blood sugar levels). Identifying and eliminating trigger foods through blood tests can also help refine your GKI. You can consult your doctor if using your GKI for therapeutic purposes.
Final Thoughts
Do the GKI test. If you don’t measure it, you don’t know. I really believe that it is impossible to effectively use ketosis for treatment purposes without follow-up. There are so many personal factors that can affect your numbers that it’s worth making a small investment in your health, getting a meter, and testing yourself regularly until you find your groove.
