Not always, but recommended

Do I need to fast?

For most blood tests fasting isn't strictly required, but it does produce more accurate results. We recommend always doing blood tests in the morning between 08:00 and 10:00, preferably while fasting. For a number of specific tests 12 hours of fasting is required.

Tests where fasting is required or strongly recommended

Fasting is essential for reliable results with these tests

Fasting required

Glucose (Blood Sugar)

12 hours fasting required

Fasting glucose is essential for diagnosing diabetes or pre-diabetes

Fasting required

Lipid Panel (Cholesterol, Triglycerides, LDL, HDL)

12 hours fasting required

Triglycerides and LDL cholesterol are strongly influenced by food intake

Fasting required

Homocysteine

12 hours fasting required

Important for cardiovascular disease and vitamin B status

Fasting required

Insulin

12 hours fasting required

For a reliable measurement of insulin levels

Fasting required

HOMA IR (Insulin Resistance)

12 hours fasting required

Measures how well your body handles sugar and insulin

Recommended

Iron & Ferritin

Fasting strongly recommended

Iron levels fluctuate with food intake; fasting provides the most reliable picture

Fasting required

Bone Enzyme (BAP Osteoporosis)

12 hours fasting required

For research into bone density and osteoporosis

Recommended

Vitamin B12 & Folic Acid

Fasting recommended

Supplements and food can temporarily influence levels

Time-sensitive

Cortisol (Stress Hormone)

Test before 10:00 AM

Not fasting, but early in the day for best results

Fasting: what's allowed and what's not?

Follow these guidelines for optimal test results

This is allowed

  • Drinking water

    Unlimited water is always allowed and encouraged

  • Light breakfast (non-fasting tests)

    Maximum 2 slices of whole wheat bread with lean topping, no butter

  • Taking medication

    Continue your medication unless your doctor has advised otherwise

This is not allowed

  • Coffee and tea with milk/sugar

    Only water is allowed during the fasting period

  • Dairy products

    Milk, yogurt, cheese can affect test results

  • Fried and fatty foods

    Can disrupt lipid values and other parameters

  • Alcohol

    Avoid alcohol 24 hours before the test

Ready for your blood test?

With this preparation you can confidently order your test.