Ketone Levels

There are three important Ketones involved in Ketogenic Diets, Acetoacetic acid (AcAc), Acetone, and Beta-hydroxybutyrate (BOHB). Their levels can vary somewhat independently, and the target levels for different results are not well defined. Blood levels of BOHB from 0.5 to around 3-5.0 mmol/L have been labeled 'nutritional ketosis' and levels over 4.0 mmol/L are probably best for treatment of Epilepsy.

1 Relative Levels

Changes in blood ketone levels during progressive starvation.

• As shown above, the ratio of AcAc to BOHB can change dramatically during progressive starvation, with BOHB rising far higher than AcAc. Also, during diabetic ketoacidosis (DKA), the ratio of BOHB:AcAc rises from normal (1:1) to as high as 10:1.
• Urine ketone levels vary with the time of day, often being lower in the morning
• The ratio between AcAc and Acetone appears reasonably constant, and is based on the spontaneous, one way decomposition of AcAc into Acetone.

2 Target Levels

There are no well-defined ketone levels at which particular changes occur. The list below is a sampling of the levels I've found used.

• The level required to be ketogenic (hyperketonemia) has been suggested as 0.2 mmol/L measured as the combination of AcAc and BOHB in whole blood as this is slightly above the levels seen in "normal" individuals.
• The book "The Art and Science of Low Carbohydrate Living" calls the range 0.5 to 5.0 mmol/L of blood ketones "nutritional ketosis"
• The follow on book "The Art and Science of Low Carbohydrate Performance" suggests that BOHB levels of 0.5 mmol/L to 3.0 mmol/L is "optimal", with benefits starting at 0.5 mmol/L and improving to 3.0 mmol/L, but levels above 3.0 mmol/L not producing additional benefits. (It is unclear what research these levels are based on.)
• For epilepsy, the recommendation is for AcAc to be 80-160 mmol/L as measured by urine dipstick, though this level is not necessarily sufficient.
• The range of 2 to 7 mmol/L or 2 to 5 mmol/L has been suggested in some literature as a "therapeutic" range.
• A study of 74 children on the ketogenic diet for epilepsy found that blood BOHB levels of greater than 4 mmol/L were correlated with better seizure control than those with lower levels.
• A 28 day study of five Parkinson's patients on the Ketogenic Diet had blood BOHB levels averaging 6.6 mmol/L (range 4.8 to 8.9) and showed some signs of improvements, though the study was too small for any conclusions to be drawn .

3 Example levels

From "Physiological roles of ketone bodies as substrates and signals in mammalian tissues":

Situation	Ketone Levels (Blood levels of AcAc + BOHB)
Fed	~0.1
Fasted 12-24 Hours	Up to 0.3
Fasted 48-72 Hours	2-3
Fasted 5-6 weeks (plateau)	~8
Post exercise	Up to 2
Late Pregnancy	Up to 1
Late Pregnancy, fasted 48 hours	4-6
Neonatal	0.5-1.0
Hypoglycemia	1-5
Controlled diabetes	Up to 25

4 See Also

• The classifications and types of Low Carbohydrate Diet.
• An introduction to the Ketogenic Diet.
• My experiences with ultrarunning on the Ketogenic Diet
  • How the Ketogenic Diet can be used for the treatment and management of disease.
    • Using the Ketogenic Diets to mitigate and treat Epilepsy
    • How Ketogenic Diets might help with Cancer
    • A look at the possible mechanisms of action of the Ketogenic Diet
  • Health Risks of the Ketogenic Diet
    • Health Checks for the Ketogenic Diet
    • Supplements for the Ketogenic Diet
  • The time frame and changes that occur with Ketoadaptation
  • What are Ketones
    • How to measure Ketones
    • What ketone levels to aim for
  • The pros and cons of the Ketogenic Diet for athletes
    • The Science of Ketogenic Exercise
  • The Types of Ketogenic Diet
    • The "traditional" Ketogenic Diet based on the Ketogenic Ratio
      • The ways the Ketogenic Ratio can be calculated
        • The different definitions of Net Carbohydrates
    • Low Glycemic Index Treatment
    • MCT Diet
      • MCT
    • Modified Atkins Diet (M.A.D.)
• My Ketogenic Recipes
• Non-Ketogenic Low Carbohydrate Diets