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Educational guide

5 blood tests for metabolic health

An evidence-based guide to the most informative blood tests and how to interpret them.

Download PDF (in Estonian)

Why these 5 tests?

A standard check-up often focuses on total cholesterol and fasting glucose alone. That misses hidden insulin resistance and chronic inflammation – the root causes of metabolic disease. Below are five tests that give a much deeper picture of your metabolic health.

Take tests fasting (12 hours without food) between 8 and 10 a.m. Avoid intense exercise and alcohol the day before.

1 · HbA1c – glycated hemoglobin

Reflects average blood sugar over the past 8–12 weeks. Unlike a single fasting reading, it shows the long-term trend.

< 5.4

Interpretation
Optimal metabolic health

5.5 – 5.6

Interpretation
Monitor and optimize lifestyle

5.7 – 6.4

Interpretation
Pre-diabetes – needs intervention

≥ 6.5

Interpretation
Diagnostic threshold for diabetes

Practical advice: check once a year; every 3–6 months if you have insulin resistance.

2 · Fasting insulin

One of the measures used when assessing early insulin resistance; it is not a diagnosis on its own. Fasting glucose can stay normal for years while insulin is already elevated.

2–5

Interpretation
Optimal metabolic flexibility

5 – 10

Interpretation
Acceptable, optimization recommended

10 – 15

Interpretation
Emerging insulin resistance

> 15

Interpretation
Clear insulin resistance

HOMA-IR = (insulin × glucose mmol/L) / 22.5. The educational reference used in the literature is < 1.5; it is not a diagnostic threshold.

3 · hsCRP – high-sensitivity C-reactive protein

Marker of systemic chronic inflammation. Low-grade chronic inflammation is a root cause of cardiovascular disease, type-2 diabetes and neurodegenerative conditions.

< 1.0

Risk
Low risk

1.0 – 3.0

Risk
Medium risk

> 3.0

Risk
High risk – needs attention

Note: do not measure during acute infection or within 2 weeks after – the result will be falsely elevated.

4 · Ferritin

Marker of iron stores. Low ferritin causes fatigue and hair loss; high ferritin suggests inflammation or fatty liver.

  • Women: optimal 50–150 ng/mL
  • Men: optimal 80–200 ng/mL
  • > 200 ng/mL – check inflammation and liver markers
  • < 30 ng/mL – iron deficiency, also check B12 and folate

5 · Lipid profile – a deeper view

Total cholesterol alone is poorly informative. Look at fractions and ratios:

Triglycerides

Educational reference
< 1.0 mmol/L

HDL

Educational reference
> 1.3 (F) / > 1.0 (M) mmol/L

Trig/HDL ratio

Educational reference
< 1.0 (strong IR marker)

ApoB

Educational reference
< 0.9 g/L (LDL particle count)

Lp(a)

Educational reference
< 30 mg/dL (genetic risk)

The Trig/HDL ratio is one of the more informative insulin-resistance markers. The figures in the table are educational references, not diagnostic thresholds – results are interpreted by a physician together with the clinical picture.

Next steps

  • Book a consultation to interpret your results: info@synage.ee
  • Repeat tests 3–6 months after lifestyle changes
  • See our free materials on insulin resistance and inflammation

Educational material – does not replace individual medical consultation, diagnosis or treatment.

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