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ketones.fyi

Ketone Level 0.4 mmol/L

Light ketosis: 0.4 mmol/L, which is 4.2 mg/dL of BHB in the blood.

Blood ketones
0.4 mmol/L
Expressed in mg/dL
The number is 4.2 mg/dL.
Usual urine strip
Trace
Breath, roughly
2–5 ppm
Stage
Light ketosis level
Typical fasting hour
around hour 15
Negative0 mg/dLTrace5 mg/dLSmall15 mg/dLModerate40 mg/dLLarge80 mg/dLVery large160 mg/dL

What 0.4 mmol/L tells you

Blood ketones of 0.4 mmol/L show light ketosis, equal to 4.2 mg/dL of BHB in the blood.

Most studies draw the line for nutritional ketosis at 0.5 mmol/L, so 0.4 mmol/L sits just under it.

Expect 0.4 mmol/L at the midpoint of the expected range at about hour 15 of fasting, after a mixed meal and without exercise.

Usually the urine strip at 0.4 mmol/L reads on the trace pad, while a breath meter shows about 2 to 5 ppm, and both results are approximate

Use the reading comparison tool to put 0.4 mmol/L beside a strip reading or a breath reading, or to include glucose in the GKI.