Your skin says a lot about what’s going on inside. This test helps you uncover the hidden factors that affect how your skin looks and feels, from hormones and stress to nutrition and inflammation. Whether you're dealing with breakouts, dryness, or simply want more glow, it gives you real insight to help you support your skin with smarter skincare, diet, and lifestyle choices.
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Struggling with skin that doesn’t feel like yours?
We see you.
If you’re dealing with adult acne, premature ageing, or skin flare-ups, it isn’t always easy to know why. Skin IQ helps you understand what’s happening beneath the surface, so you can make more informed choices, not just cover up the symptoms.
Forget serums, we're going deeper.
50 biomarkers.One powerful insight.
From omega-3 and magnesium to blood sugar and immune markers, we test what matters, so you can support your skin from the inside out.
The missing link in skin health
Get your glow back – why magnesium matters
Magnesium is your skin’s silent stress-buffer. It helps to temper cortisol spikes, supports barrier lipids, and locks in hydration. Levels often dip with low-fibre diets or alcohol consumption, resulting in redness and breakouts. Checking magnesium can uncover a simple, often-missed fix.
Get the answers you need
It’s skincare, with science behind it.
Buy online, take your test with a trained nurse at home or at a local clinic, then see what’s really going on inside with a clear, personalised report.
What's in the test?
Adrenal hormones
Cortisol
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Cortisol is a stress hormone produced by the adrenal glands. It is vital to survival given its role in functions such as immunity, regulating blood pressure and releasing insulin for blood sugar maintenance.
Clotting status
MPV
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MPV, or Mean Platelet Volume, is a measurement of the average size of your platelets. Platelets are fragmented cells within the blood that aid the process of clot formation. MPV provides an indication of platelet production in your bone marrow.
Platelet count
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Platelets or clotting cells are the smallest type of blood cell. They are formed in the bone marrow and are important in blood clotting. When bleeding occurs, the platelets swell, clump together and form a sticky plug (a clot) which helps stop the bleeding.
Diabetes
HbA1c
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Haemoglobin A1c (HbA1c), also known as glycated haemoglobin, is a longer-term measure of glucose levels in your blood than a simple blood glucose test. Glucose attaches itself to the haemoglobin in your red blood cells, and as your cells live for around 12-16 weeks, it gives us a good indication of the average level of sugar in your blood over a 3-month period.
A raised HbA1c result points to diabetes or an increased risk of developing diabetes, which can have a significant impact on your lifespan and quality of life. Complications of uncontrolled diabetes include heart disease, kidney disease, eye problems, and vascular conditions. It can also contribute to mental health problems. And men with diabetes are three times more likely to have erectile dysfunction. Keeping your HbA1c within a normal range can help you reduce the risk of these conditions.
A raised HbA1c result points to diabetes or an increased risk of developing diabetes, which can have a significant impact on your lifespan and quality of life. Complications of uncontrolled diabetes include heart disease, kidney disease, eye problems, and vascular conditions. It can also contribute to mental health problems. And men with diabetes are three times more likely to have erectile dysfunction. Keeping your HbA1c within a normal range can help you reduce the risk of these conditions.
Hormones
Free androgen index
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The free androgen index (FAI) is a calculation used to determine the amount of testosterone which is free (unbound) in the bloodstream. Most testosterone is bound to proteins sex hormone binding globulin and albumin and is not available to interact with the body's cells. The FAI is a calculation based on the ratio of testosterone and SHBG and is a measure of the amount of testosterone that is available to act on the body's tissues. The free androgen index is used in women to assess the likelihood of polycystic ovarian syndrome. In men, free testosterone gives a better indication of testosterone status.
Free testosterone - calc
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Most testosterone circulating in the blood is bound to proteins, in particular SHBG and albumin; only 2-3 % of testosterone is free and available to cells. This test uses an algorithm to calculate the level of free or unbound testosterone in relation to total testosterone, SHBG and albumin.
FSH
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Follicle Stimulating Hormone (FSH) is produced in the pituitary gland and is important for women in the production of eggs by the ovaries and for men in the production of sperm. In the first half of the menstrual cycle in women, FSH stimulates the enlargement of follicles within the ovaries. Each of these follicles will help to increase oestradiol levels. One follicle will become dominant and will be released by the ovary (ovulation), after which follicle stimulating hormone levels drop during the second half of the menstrual cycle. In men, FSH acts on the seminiferous tubules of the testicles where they stimulate immature sperm cells to develop into mature sperm.
LH
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Luteinising Hormone (LH) is produced by the pituitary gland and is important for male and female fertility. In women it governs the menstrual cycle, peaking before ovulation. In men it stimulates the production of testosterone.
Oestradiol
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Oestradiol is the strongest of the three oestrogens. It's labelled a female hormone but it's made in both the ovaries and testes. It's responsible for the growth of breast tissue, the female reproductive system, and male sexual function.
In pre-menopausal women, oestradiol levels vary throughout the monthly cycle, peaking just before ovulation. Levels are lowest after menopause when the ovaries stop producing eggs. Low oestradiol levels in women can cause many symptoms associated with the menopause, including hot flushes, night sweats, and changes in mood. It can also increase the risk of osteoporosis (a condition where the bones become less dense).
In men, oestradiol levels tend to increase slightly with age as testosterone levels decline. Too much oestradiol in men can contribute to fertility problems, gynecomastia (enlarged breast tissue), and erectile dysfunction.
Testosterone
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Testosterone is a hormone that causes male characteristics. For men, it helps to regulate sex drive and has a role in controlling bone mass, fat distribution, muscle mass, strength and the production of red blood cells and sperm. Testosterone is produced in the testicles of men and, in much smaller amounts, in the ovaries of women. Testosterone levels in men naturally decline after the age of 30, although lower than normal levels can occur at any age and can cause low libido, erectile dysfunction, difficulty in gaining and maintaining muscle mass and lack of energy. Although women have much lower amounts of testosterone than men, it is important for much the same reasons, playing a role in libido, the distribution of muscle and fat and the formation of red blood cells. All laboratories will slightly differ in the reference ranges they apply because they are based on the population they are testing. The normal range is set so that 95% of men will fall into it. For greater consistency, we use the guidance from the British Society for Sexual Medicine (BSSM) which advises that low testosterone can be diagnosed when testosterone is consistently below the reference range, and that levels below 12 nmol/L could also be considered low, especially in men who also report symptoms of low testosterone or who have low levels of free testosterone.
Inflammation
hs-CRP
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C-Reactive Protein (CRP) is an inflammation marker used to assess whether there is inflammation in the body - it does not identify where the inflammation is located. High Sensitivity CRP (CRP-hs) is a test used to detect low-level inflammation thought to damage blood vessels which can lead to a heart attack or stroke. When you suffer a serious injury or infection you experience significant inflammation around the site of injury - such as the swelling around a twisted ankle. Any injury like this will cause your CRP-hs to rise.
Iron status
Ferritin
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Ferritin is a protein which stores iron in your cells and tissues. Usually, the body incorporates iron into haemoglobin to be transported around the body, but when it has a surplus, it stores the remaining iron in ferritin for later use. Measuring ferritin levels gives us a good indication of the amount of iron stored in your body.
Iron
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Iron is a mineral that is essential for life. It is a component of haemoglobin, a protein in our red blood cells that is responsible for transporting oxygen around our body. If we don't have enough iron, our haemoglobin levels fall and we can't get sufficient oxygen to our cells. This can cause symptoms which include fatigue, dizziness, and shortness of breath. Serum iron is a very transient reading and can be influenced by the amount of iron-rich food in your diet in the days before your blood test. For this reason, iron is rarely looked at on its own, and is interpreted alongside other markers in an iron status test.
TIBC
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Total iron-binding capacity (TIBC) is a measure of the ability of your body to efficiently carry iron through the blood.
Transferrin saturation
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Transferrin is made in the liver and is the major protein in the blood which binds to iron and transports it round the body. This test measures how much this protein is 'saturated' by iron.
UBIC
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Kidney health
Creatinine
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Creatinine is a chemical waste molecule that is generated from normal muscle metabolism. Measurement of this is an indicator of the levels of other waste products in the body. Creatinine is also an accurate marker of kidney function, and may help in diagnosing kidney disease.
eGFR
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The estimated glomerular filtration rate (eGFR) assesses how well the kidneys are working by estimating the amount of blood filtered through the kidneys. The glomeruli are tiny filters in the kidneys responsible for removing waste products. If these filters do not do their job properly, kidney function can be impaired. The eGFR calculation is an estimate of actual glomerular filtration rate, calculated using your age, gender, ethnicity, and serum creatinine levels.
Urea
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Urea is a waste product produced by the body when it breaks down proteins in the liver. Once the urea is made, it is transported to the kidneys, which filter it out of the blood and remove it from the body in the form of urine. Measuring the levels of urea in the blood can therefore reflect how well both the liver and the kidneys, are functioning. It is important to note that even if one kidney is severely damaged but the other is functioning perfectly, results may still return as normal.
Liver health
ALP
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Alkaline phosphatase (ALP) is an enzyme found mainly in the liver and bones. Measuring it can indicate ongoing liver, gallbladder or bone disease.
ALT
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Alanine transferase (ALT) is an enzyme which is mostly found in the liver, but is also found in smaller amounts in the heart, muscles and the kidneys. If the liver is damaged, ALT is leaked into to bloodstream. As ALT is predominantly found in the liver, it is usually an accurate marker for liver inflammation and can indicate liver damage caused by alcohol, fatty liver, drugs or viruses (hepatitis).
Bilirubin
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Bilirubin is a product of the breakdown of haemoglobin from red blood cells. It is removed from the body via the liver, stored and concentrated in the gallbladder and secreted into the bowel. It is removed from your body through urine and faeces. Bilirubin causes the yellowish colour you sometimes see in bruises, due to red blood cells breaking down underneath the skin.
Gamma GT
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Gamma GT, also known as gamma-glutamyl transferase (GGT), is a liver enzyme which is raised in liver and bile duct diseases. It is used in conjunction with ALP to distinguish between bone or liver disease. Gamma GT is also used to diagnose alcohol abuse as it is raised in 75% of long term drinkers.
Minerals
Magnesium - serum
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Magnesium is found in fibre-rich foods such as green leafy vegetables, avocados, bananas, wholemeal bread and brown rice as well as in fish and meat. Excess magnesium exposure can cause breathing problems, skin and eye irritation, flu-like symptoms and an upset stomach. Low magnesium can cause muscle aches and pains, fatigue, osteoporosis, an irregular heartbeat and high blood pressure. Low magnesium is associated with heart disease, artherosclerosis, stroke and diabetes.
Zinc
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Omega fatty acids
ARA : EPA
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Omega-3 essential fatty acids such as EPA are responsible for controlling inflammation, brain development, and regulating blood pressure. Omega-6 fatty acids such as ARA are thought to have a pro-inflammatory role in the body, while omega-3 fatty acids like ERA are thought to have an anti-inflammatory role.
Omega 3 index
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The Omega-3 Index is the proportion of long-chain omega-3s, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) of all fatty acids in your blood, specifically your red blood cell membranes. Aiming for an Omega-3 Index >8% helps maintain optimum heart, brain, eye, and joint health.
Proteins
Albumin
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Albumin is a protein which is made mainly in the liver. It helps to exert the osmotic pressure which holds water within the blood. It also helps carry nutrients and medications and other substances through the blood and is important for tissue growth and healing. Albumin also carries hormones around the body, therefore measuring the amount of albumin in the blood can help us calculate how much hormone is available to your tissues.
Globulin
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Globulin is an umbrella term for a set of different proteins that the immune system and the liver produce. Certain globulins bind with haemoglobin while others transport metals, such as iron, in the blood. Additionally, there is a certain type of globulin known as an immunoglobulin, (another name for an antibody) which helps to fight infection in the body.
SHBG
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SHBG (sex hormone binding globulin) is a protein which transports the sex hormones (testosterone, oestrogen and dihydrotestosterone (DHT)) in the blood.Hormones which are bound to SHBG are inactive which means that they are unavailable to your cells. Measuring the level of SHBG in your blood gives important information about your levels of free or unbound hormones which are biologically active and available for use.
Total protein
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Total Protein represents the sum of the proteins albumin and globulin in your blood. Albumin and globulin have a range of functions including keeping blood within vessels, transporting nutrients and fighting infection. Abnormal levels can indicate malnutrition as well as a liver or kidney disorder.
Red blood cells
Haemoglobin
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Haemoglobin is a protein in red blood cells which carries oxygen around the body and gives the blood its red colour. This test measures the amount of haemoglobin in the blood and is a good measure of the blood's ability to carry oxygen around the body.
Haematocrit
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HCT (haematocrit) measures the amount of space (volume) within the blood that is taken up by red blood cells.
MCH
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MCH (mean corpuscular haemoglobin) measures the average amount of haemoglobin contained in one of your red blood cells.
MCHC
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MCHC (mean corpuscular haemoglobin concentration) is the average concentration of haemoglobin in your red blood cells. Haemoglobin is a molecule which allows red blood cells to transport oxygen around the body.
MCV
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MCV (mean corpuscular volume) reflects the average size of your red blood cells. This is important to measure, as it can indicate how much oxygen your cells are likely to be transporting around the body.
RDW
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Red blood cell distribution width (RDW) indicates whether your red blood cells are all the same size, or different sizes or shapes. Normally cells are fairly uniform both in size and in shape, but some blood disorders may cause your red blood cells to form in abnormal sizes. This test measures the difference between the largest and the smallest red blood cell.
Red cell count
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Red Blood Cell (RBC) Count analyses the number of red blood cells in the blood. Red blood cells carry oxygen from the lungs to the rest of the body, where it can be used to fuel energy processes such as movement and respiration. They also carry carbon dioxide produced from cells back to the lungs so that it can be exhaled.
Thyroid hormones
Free T3
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Triiodothyronine (T3) is the more active of the two thyroid hormones produced by the thyroid gland. Most T3 is bound to protein in the blood. Free T3 measures the level of T3 that is free, or unbound to protein, and is available to regulate metabolism.
Free thyroxine
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Thyroxine (T4) is one of two hormones produced by the thyroid gland. It works to speed up the rate of your metabolism. Most T4 is bound to carrier proteins in the blood - it is only the free, or unbound, T4 that is active in the body, which is measured in this test. Free T4 is the less active of the two main thyroid hormones. To have an impact on your cells it needs to convert to the more active T3 when your body needs it.
TSH
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Thyroid stimulating hormone (TSH) is produced in the pituitary gland in order to regulate the production of thyroid hormones thyroxine (T4) and triiodothyronine (T3) by the thyroid gland. If thyroid hormones in the blood are low, then more TSH is produced to stimulate the thyroid gland to produce more of them. If thyroid hormone levels are high, then the pituitary produces less TSH to slow the production of thyroid hormones. If TSH is too high or too low, it normally signifies that there is a problem with the thyroid gland which is causing it to under or over produce thyroid hormones. Sometimes a disorder of the pituitary gland can also cause abnormal TSH levels.
Vitamins
Folate - serum
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Folate is a B vitamin which acts as a coenzyme in the metabolism of amino acids. It is also vital for the synthesis of purines and pyrimidines which are essential for DNA synthesis and red cell formation. Folate is also especially important during the first trimester of pregnancy so if you are thinking of becoming pregnant it is important to make sure your folate levels are normal.
Vitamin B12 - active
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Vitamin B12 is important for production of red blood cells which carry oxygen around the body. B12 is also involved in metabolism and the nervous system and prolonged lack of vitamin B12 may cause nerve damage. Although Vitamin B12 is almost entirely found in animal-based foods, many vegetarian and vegan products, especially plant milks are now fortified with Vitamin B12.
Vitamin D
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Despite its name, vitamin D is actually a hormone that’s produced by your skin when it’s exposed to sunshine. Before your body can use vitamin D produced by sun exposure (known as vitamin D3), it must be converted into another form called 25 hydroxycholecalciferol (25 OH). Vitamin D (25 OH) is the major circulating form of vitamin D, and so your vitamin D (25 OH) level is considered the most accurate indicator of vitamin D supply to your body.
Vitamin D is essential for healthy bones and teeth, as it helps your body absorb calcium. It also plays a role in muscle health, immune function, and mental health.
Low vitamin D symptoms include muscle weakness, mood swings, and fatigue. Many people in the UK have low vitamin D levels, and people with dark skin and people who don’t spend much time outdoors are particularly at risk.
Small amounts of vitamin D can be obtained from food, especially oily fish, eggs, and vitamin-D fortified foods. But if you have a vitamin D deficiency, you’re unlikely to be able to improve your levels by food alone.
White blood cells
Basophils
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Basophils are a type of white blood cell that protect your body from bacteria and parasites such as ticks. They also play a role in allergic reactions.
Eosinophils
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Eosinophils are a type of white blood cell that are responsible for removing parasitic infections and regulating inflammation to mark an infected site. They also play a role in allergy and in asthma.
Lymphocytes
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Lymphocytes are a type of white blood cell which fight bacterial and viral infections. They are the subset of white blood cells involved in the more specific response to infections, which can identify and differentiate between different foreign organisms that enter the body. As well as fighting infection, they produce antibodies and memory cells to help to prevent future infections from the same germ. Lymphocytes include T cells, B cells and natural killer cells.
Monocytes
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Monocytes are a type of white blood cell that surround and destroy germs and dead or damaged cells from the blood. The heat and swelling that you feel when a body part is inflamed, for example after a cut on your finger, is caused by the activities of these cells.
Neutrophils
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Neutrophils are the most abundant type of white blood cell in the body and are responsible for helping your body fight infection. When a germ is initially detected by the body, neutrophils are the defence system which go out and attack the germ before any of your other white blood cells. When neutrophils are low you can be more vulnerable to illness and infection.
White cell count
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White Blood Cell (WBC) Count measures the number of white blood cells in the blood. White blood cells are key to your body's immune system. They fight infections and protect your body from foreign invaders such as harmful germs and bacteria. Additionally, they produce many antibodies and memory cells to protect you from further infections with the same germ.
How to prepare for your test
Prepare for your Skin IQ Blood Test by following these instructions.
Sample collection and timing
- Take your sample between 6am and 10am.
- Take this test when any symptoms of short-term illness have settled.
- Avoid heavy exercise for 48 hours beforehand.
- If you have an unusual sleep pattern, your cortisol results may be unreliable. If you must test, do so within 2 hours of waking and inform us in the supporting information.
Periods and contraception
- Take this test two to five days after the start of your period, ideally on day three. It can be taken any time if you do not have periods.
- Hormonal contraception can affect the results of this test. Taking a break from this and waiting for your periods to restart before your blood test will give more accurate results.
Fasting and hydration
- For most accurate omega fatty acid results, do not eat or drink anything other than water for 12 hours prior to your test. If you take medication then you are allowed to take it as you would normally.
- Stay well hydrated before your test.
Medications and supplements
- Do not take biotin supplements for two days before this test, discuss this with your doctor if it is prescribed.
- If you take omega-3 supplements, wait until after your test to take them.
- Do not take vitamin B12 for two weeks prior to this test. If your B12 is prescribed ask your doctor whether to stop.
- If you take thyroxine, you can take your medication as usual, either before or after your blood test. However, if you take desiccated thyroid extract (DTE) or liothyronine, it's best to take it after you've collected your sample. Please let us know in your supporting information if you take amiodarone or lithium as these can affect your thyroid function results.
- Take your sample at least 24 hours after any vitamin or mineral supplements.
- Corticosteroid medication can affect this test, ask your doctor whether to stop before testing.
Test limitations
This test does not directly measure collagen levels, oxidative stress, or the presence of specific skin conditions. Instead, it looks at internal biomarkers, such as hormones, nutrients, and inflammatory markers that can influence skin health. Results should be interpreted alongside other factors like skincare, lifestyle, and medical history.
FAQs
What is the Skin IQ Blood Test?
The Skin IQ Blood Test is a skin-focused blood panel that measures internal health markers, including hormones, nutrients, and inflammation, that can influence skin concerns such as acne, premature ageing, dullness, and poor skin texture.
Can this blood test tell me what’s causing my acne or skin issues?
The Skin IQ Blood Test can highlight internal imbalances that may contribute to acne, breakouts, or poor skin quality, including hormone imbalances, inflammation, or vitamin and mineral deficiencies. This test can’t diagnose specific skin conditions.
Is the Skin IQ test suitable for men and women?
Yes. This test is suitable for anyone interested in understanding how their internal health may be affecting their skin.
Hormone reference ranges are adjusted by age and gender where appropriate.
Can I take this test while using skincare treatments or supplements?
Yes, but some supplements (like zinc, magnesium, or biotin) can affect your results. For the most accurate picture, you may wish to pause certain supplements a few days before testing, unless advised otherwise by a healthcare provider.
How can a blood test help improve my skin?
By identifying internal factors that may be undermining your skin, like low nutrients, high inflammation, or hormone imbalances, Skin IQ gives you insights to tailor your diet, skincare routine, or treatment choices more effectively.
Is this a blood test for anti-ageing or collagen?
This test doesn’t directly measure collagen levels, but it assesses nutrients and hormones (such as zinc, oestradiol, and thyroid hormones) that are known to support collagen production and skin repair.