Fasting glucose
Glucose is your blood sugar — the main immediate source of energy for your cells. The fasting level (after an overnight fast) shows how well your body regulates sugar with the help of the hormone insulin. It is one of the key metabolic markers.
| Rating | Range |
|---|---|
| Talk to a doctor | below 3 mmol/L |
| Worth improving | 3 – 3.9 mmol/L |
| Good | 3.9 – 6.1 mmol/L |
| Worth improving | 6.1 – 7 mmol/L |
| Talk to a doctor | 7 mmol/L and above |
Why it matters
Per WHO/ADA, persistently elevated glucose is a diagnostic criterion for pre-/diabetes and puts strain on your blood vessels.
If it’s low
Low glucose (hypoglycemia) is rare in people without diabetes; it can result from a long fast, excessive alcohol or medications. Signs: trembling, sweating, hunger, confusion.
If it’s high
Elevated fasting glucose means the body regulates sugar with more difficulty — often early insulin resistance. 5.6–6.9 mmol/L = prediabetes range (a warning, mostly reversible); ≥7.0 (on repeat testing) = diabetes (confirmed by a physician).
What to do
The prediabetes range is an excellent opportunity — with movement and diet it often reverses. Today: protein/fiber before starch, a walk after meals. Confirm a value of ≥7.0 with your doctor (a repeat test / HbA1c).
Read together with
HbA1c · Fasting insulin · Triglycerides · HDL cholesterol
Part of the guide: Blood sugar & insulin →
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This content is for information only and is not a substitute for medical advice. Talk to your doctor about your results.
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