InsideTracker blood test: 35 biomarkers

SHBG stands for sex hormone binding globulin. It is a protein made by the liver. SHBG binds testosterone tightly and oestradiol somewhat more loosely. Hormone bound to SHBG cannot act in the tissues. SHBG therefore determines how much of your total testosterone is genuinely available. SHBG is not itself a sex hormone but a transport protein. Results are reported in nmol/l. Normal values differ by sex and by age, and in men SHBG rises as they get older. An SHBG should therefore be assessed alongside total testosterone, never on its own.

TSH is thyroid-stimulating hormone. The pituitary gland makes it, and uses it to drive your thyroid. At the laboratory that runs the test the usual adult range runs from 0.27 to 4.20 mE/L. A high TSH usually fits an underactive thyroid. A low value usually fits an overactive one. That direction feels inverted, and it is. TSH is the pituitary signal, not the thyroid hormone itself. Laboratories use slightly different limits from one another. Always read the reference value printed on your own result. And a single measurement is never a diagnosis.

Your ALT value shows how much alanine aminotransferase is in your blood. This enzyme sits mainly in the liver. That makes ALT the most liver-specific of the routine enzymes. When it reaches the blood, liver cells have been damaged. In adult men the reference range runs to 45 u/l, and in women to 34 u/l. A mildly raised result is common and has several causes. Fatty liver leads that list, well ahead of alcohol and hepatitis.

LDL cholesterol is the amount of cholesterol carried inside LDL particles, the particles that can build up in the artery wall. That is where its nickname comes from: the bad cholesterol. Two things rarely appear on a report. First, in a routine lipid panel LDL is usually not measured but calculated from your total cholesterol, your HDL and your triglycerides. Second, the 3.0 mmol/l upper limit is a population reference interval, not a target. What counts as a good LDL for you is decided by your overall cardiovascular risk, not by the line printed on the page.

GGT (gamma-glutamyl transferase) is a liver and bile duct enzyme that serves as one of the most sensitive markers for hepatobiliary disorders. It is particularly responsive to alcohol consumption and may be elevated in bile duct obstruction, liver disease, and with certain medications.

Cortisol is the body's primary stress hormone, produced by the adrenal glands. It regulates metabolism, immune responses, and the sleep-wake cycle. Levels follow a natural daily rhythm, peaking in the morning and declining throughout the day.

DHEA-S (dehydroepiandrosterone sulfate) is the most abundant adrenal hormone and serves as a precursor to both oestrogen and testosterone. It declines naturally with age and reflects overall adrenal reserve.

Estradiol (E2) is the most potent form of estrogen, playing a key role in reproductive health, bone density, and cardiovascular function. Abnormal levels may indicate hormonal imbalances that your healthcare provider can help evaluate.

Free testosterone is the unbound, bioavailable form of testosterone that can directly enter cells and activate receptors. It may indicate your body's functional androgen activity. Your healthcare provider can help interpret what your levels mean.

Total testosterone measures the combined amount of bound and free testosterone in the blood. As the primary androgen, testosterone may influence muscle mass, bone density, libido, mood, and energy levels in both men and women.

Folate, also known as vitamin B9, is a water-soluble vitamin involved in cell division and DNA synthesis. Adequate folate levels are considered important for overall health and may be particularly relevant during periods of rapid growth.

Vitamin B12 is considered essential for red blood cell formation, neurological function, and DNA synthesis. Deficiency may develop gradually and is sometimes associated with dietary patterns. Healthcare providers can help interpret your results.

Calcium is the most abundant mineral in the body, essential for strong bones and teeth, muscle contraction, nerve signalling, and blood clotting. Most calcium is stored in bones and teeth, with a small amount circulating in the blood.

Ferritin is a protein that stores iron, so your ferritin level shows how large your iron reserve is. Serum iron only measures how much iron is circulating in your blood at that moment; ferritin describes the reserve behind it. That reserve empties before your haemoglobin falls, so a low ferritin can already cause symptoms while your blood count still looks normal. Ferritin also rises with inflammation, infection and liver strain, which is why it can only be read properly alongside a CRP. Commonly used reference values are 30 to 400 µg/l for men and 15 to 150 µg/l for women, but your own laboratory report is what counts.

Serum iron measures the amount of circulating iron in your blood. Iron is essential for haemoglobin production, oxygen transport, and energy metabolism throughout the body.

Magnesium is an essential mineral involved in over 300 enzymatic reactions in the body, including energy production, muscle and nerve function, blood sugar regulation, and bone development.

Potassium is an essential electrolyte and mineral that helps regulate heartbeat, muscle contractions, nerve signals, and fluid balance. It is one of the most important minerals for cardiovascular health.

A progesterone blood test measures the level of progesterone, a hormone essential for the menstrual cycle and pregnancy. Progesterone is primarily produced by the ovaries after ovulation and plays a key role in preparing the uterus for implantation.

Sodium is a vital electrolyte that regulates fluid balance, blood pressure, and nerve and muscle function. It is the primary cation in extracellular fluid and is closely regulated by the kidneys.

Transferrin is the main protein responsible for transporting iron in the blood. It carries iron from the gut and storage sites to cells that need it, including bone marrow for red blood cell production.

C-Reactive Protein (CRP) is a protein produced by the liver in response to inflammation. It is a general marker of inflammation and can rise rapidly during infections, injuries, or chronic inflammatory conditions.

Fasting glucose measures the level of sugar (glucose) in your blood after an overnight fast. It is one of the primary tests used to screen for and monitor diabetes and pre-diabetes.

HbA1c (glycated haemoglobin) reflects your average blood sugar levels over the past 2-3 months. It is the gold standard for long-term blood sugar monitoring and diabetes management.

Apolipoprotein B (ApoB) is the main protein on LDL and other atherogenic lipoproteins. Each atherogenic particle carries exactly one ApoB molecule, making it a precise measure of the total number of particles that can contribute to plaque formation.

HDL cholesterol is the amount of cholesterol carried inside the HDL particles in your blood. Those particles pick cholesterol up from your tissues and from the artery wall and take it back to the liver. That transport is what earned HDL the nickname good cholesterol. The nickname is misleading. HDL is above all a mirror of your metabolism: the value drops with excess weight, insulin resistance, smoking and inactivity, and it is those factors that carry the risk. Drugs that raise HDL substantially do not reduce the number of cardiovascular events. And more is not always better: at very high values, mortality in large population studies turns back upwards. So never read your HDL on its own. It only takes on meaning alongside your triglycerides, your LDL and your overall risk profile.

Total cholesterol measures the combined amount of HDL, LDL, and VLDL cholesterol in your blood. It provides an overview of your lipid status but should be interpreted alongside individual components for a complete cardiovascular risk picture.

Albumin is the most abundant protein in the blood, produced by the liver. It maintains fluid balance, transports hormones and nutrients, and serves as an indicator of liver and kidney function.

Your AST value shows how much aspartate aminotransferase is circulating in your blood. It is an enzyme that leaks out whenever cells are damaged. AST sits in the liver, but equally in skeletal muscle, heart muscle, kidneys, brain and red blood cells. That is why a raised AST is not, on its own, a liver value. A hard training session the day before explains the result more often than liver disease does. The reference range runs up to 35 u/l in men and 31 u/l in women. What the number means only becomes clear alongside ALT, gamma-GT and CK.

Vitamin D is a fat-soluble vitamin that plays a key role in calcium absorption, bone health, and immune function. It is primarily produced in the skin through sunlight exposure and can also be obtained from certain foods and supplements.

Fasting insulin measures the amount of insulin in your blood after an overnight fast. It helps assess how efficiently your body manages blood sugar and can reveal insulin resistance before glucose levels become abnormal.

A leukocyte differential test measures the relative proportions of different types of white blood cells in your blood. It provides a detailed breakdown of your immune cell populations, offering valuable insight into your immune system's function.

Creatine kinase (CK) is an enzyme found primarily in the heart, brain, and skeletal muscles. When muscles are damaged or stressed, CK is released into the bloodstream, making it a useful marker of muscle health.

Transferrin saturation measures the percentage of the iron-transport protein transferrin that is occupied by iron. It is a key indicator of your body's iron status and helps distinguish between different causes of iron-related disorders.

Triglycerides are the most common type of fat in the body, used for energy storage. Elevated levels may be associated with increased risk of cardiovascular disease, especially when combined with other lipid abnormalities.

A basic blood count measures three core values in your blood: hemoglobin, white blood cells and platelets. Together they say something about oxygen transport, immune defence and clotting. It is a simple baseline check, without the red-cell indices and white-cell differential of a complete blood count.