As you might have suspected, there isn’t a one-size fits all answer to this question. Part of the answer depends on what your goals are.
The optimal ketone levels you’ll want to achieve will likely be different depending on whether you’re looking to lose weight, get improved mental clarity, improve your athletics performance, or to cure/prevent illnesses like cancer. And the numbers may also vary depending on your body’s current insulin resistance (e.g., if you have type 2 diabetes or if you’re pre-diabetic then your optimal levels at the beginning might be different from someone who has healthy levels of blood glucose).
Bearing all of those different factors in mind, below are some ranges proposed by different ketogenic diet experts.
NOTE – again, these ketone levels are for optimal nutritional ketosis and should not be used if you’re a type 1 diabetic!
Dr. Stephen Phinney, MD, PhD and Jeff Volek, PhD., RD
Most people have based their optimal ketone numbers on the recommendations in The Art and Science of Low Carbohydrate Performance: “‘light nutritional ketosis’ is between 0.5mmol/L and 1.0mmol/L and ‘optimal ketosis’ is between 1.0mmol/L and 3.0mmol/L.”
Dr. Thomas Seyfried
Dr. Thomas Seyfried, a professor of biology at Boston College who researches cancer and the uses of a ketogenic diet in curing and preventing cancer, states in the The Complete Guide to Fasting book: “The key to therapy is prolonged therapeutic ketosis (blood ketones in the range of 3–6mM), together with reduced blood glucose levels (3–4 mM).”
Dominic D’Agostino is an assistant professor in University of South Florida and his lab researches how a ketogenic diet can aid neurological diseases. In a 2014 podcast with Chris Kelly from Nourish Balance Thrive, Dominic stated: “What’s the optimal level of ketones? I think anecdotally and from the data that I’ve seen, I think somewhere between 1.5 and 3 is optimal.”
Luis from Ketogains.com who helps many bodybuilders on a ketogenic diet has repeatedly suggested that search for high ketone levels is not always beneficial. He regularly tells people: “don’t chase ketones; chase results.”
Marty, an engineer who runs the website and Facebook group, Optimising Nutrition, states that: “If your aim is exercise performance or fat loss then ketones between 0.5mmol/L and 1.3mmol/L might be all you need to aim for. I also think loading up on dietary fat at the expense of getting adequate protein, vitamins and minerals may be counterproductive in the long term.”
Marty also points out that not everyone on a ketogenic diet will get high levels – for example, Sami Inkenen only had around 0.6mmol/L when he was rowing from the US to Hawaii on an 80% fat diet.
As Certified Nutrition Specialist Amy Berger, CNS, NTP, says, “Don’t compare your results to someone else’s, and don’t let anyone “ketone shame” you on social media. It’s not a contest or a race. Someone might feel like a total rock star with [ketone level] at “only” 0.6, while someone else might not notice any difference unless their ketones are above 2.0. It’s entirely individual and the only competition you’re in is to feel your best.”
Weight-loss: above 0.5mmol/L
Improved athletic performance: above 0.5mmol/L
Improved mental performance: 1.5-3mmol/L
Therapeutic (e.g., to prevent or cure certain illnesses): 3-6mmol/L
Again, these are general ranges and if yours doesn’t fall within the range, it’s not a definitive indicator that you’re doing something wrong, but it is a helpful guide to ensure you think about tweaking and testing your keto diet to see if something can be improved.
The above Content is an extract from an article written by Louise Hendon and published on ketosummit.com