Blood test markers, explained

What each marker measures, why it's tested and which panels include it — so you can book exactly what you need, with no GP referral.

Bone & minerals

Phosphate

Phosphate is a mineral important for bone health and energy processes in the body. Its blood level is measured…

Fertility

Progesterone

Progesterone is a hormone produced mainly by the ovaries after ovulation and by the placenta in pregnancy. Its…

Full blood count

Full Blood Count (FBC)

The full blood count is a group of measurements describing the numbers and characteristics of red cells, white…

Heart & cholesterol

Apolipoprotein B

Apolipoprotein B is a protein found on cholesterol-carrying particles such as LDL, and it reflects the number …

Lipoprotein (a)

Lipoprotein (a) is a particle in the blood related to LDL cholesterol, and its level is largely determined by …

Total Cholesterol

Total cholesterol measures the overall amount of cholesterol, a fatty substance, in the blood. It is one compo…

Triglycerides

Triglycerides are a type of fat carried in the blood and reported as part of a lipid profile. Their level can …

Hormones

Cortisol

Cortisol is a hormone produced by the adrenal glands that helps regulate metabolism, the stress response and o…

Oestradiol

Oestradiol is the main form of oestrogen and an important sex hormone in both women and men. Its blood level r…

Prolactin

Prolactin is a hormone produced by the pituitary gland, best known for its role in breast milk production. It …

Testosterone

Testosterone is a sex hormone present in both men and women, produced mainly by the testes, ovaries and adrena…

Inflammation

C-Reactive Protein (CRP)

C-reactive protein is a substance made by the liver that rises in the blood in response to inflammation in the…

Iron & anaemia

Ferritin

Ferritin is the body’s main iron-storage protein, and its blood level reflects the amount of iron held in rese…

Serum Iron

Serum iron measures the amount of iron circulating in the blood bound to transport proteins. It forms one part…

Transferrin

Transferrin is the main protein that transports iron around the body in the blood. Its level is part of a full…

Kidney

Creatinine

Creatinine is a waste product from normal muscle activity that is filtered out by the kidneys. Its blood level…

Cystatin C

Cystatin C is a protein produced by cells throughout the body and cleared by the kidneys, making it a marker o…

Potassium

Potassium is an electrolyte important for nerve signalling and normal heart and muscle function. Its blood lev…

Sodium

Sodium is an electrolyte that helps regulate fluid balance and nerve and muscle function. Its blood level is p…

Urea

Urea is a waste product formed when the body breaks down protein, and it is removed by the kidneys. Its blood …

Uric Acid

Uric acid is a waste product formed from the breakdown of purines, substances found in the body and in some fo…

Liver

Albumin

Albumin is the most abundant protein in the blood, made by the liver, and it helps maintain fluid balance and …

Metabolic

Adiponectin

Adiponectin is a hormone produced by fat tissue that is involved in how the body handles glucose and fats. It …

Creatine Kinase (CK)

Creatine kinase is an enzyme found mainly in muscle tissue, including skeletal and heart muscle. Its blood lev…

HbA1c

HbA1c reflects the average amount of glucose attached to haemoglobin in red blood cells over the preceding wee…

Insulin

Insulin is a hormone made by the pancreas that helps move glucose from the blood into cells. Its level reflect…

Pancreas

Lipase

Lipase is an enzyme produced mainly by the pancreas that helps digest fats. Its blood level is measured within…

Prostate

Total Prostate Specific Antigen (PSA)

Prostate specific antigen is a protein produced by the prostate gland and measurable in the blood. The total P…

Thyroid

Thyroid Stimulating Hormone (TSH)

TSH is a hormone made by the pituitary gland that signals the thyroid gland to produce thyroid hormones. Its b…

Vitamins & minerals

Magnesium

Magnesium is a mineral involved in many processes in the body, including muscle and nerve function. The test m…

Vitamin B12

Vitamin B12 is a nutrient needed for the normal function of the nervous system and the formation of red blood …

Vitamin D

The vitamin D test measures the level of vitamin D circulating in the blood, reflecting the body’s overall vit…

Zinc

Zinc is an essential mineral that supports immune function, wound healing and many enzyme systems. The blood t…

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