Blood Tests for Over 40s: What to Check, Why It Matters & What the NHS Misses (UK 2026)

Why your 40s are a turning point for health

The decade between 40 and 50 is when the risk trajectories for cardiovascular disease, type 2 diabetes, thyroid dysfunction, hormonal change, and nutritional deficiency all begin to steepen. None of these conditions announce themselves clearly at first. Most people in their early 40s feel broadly well — until they do not.

The UK’s leading preventive health bodies recognise this. The NHS Health Check programme starts at age 40 precisely because this is when cardiovascular risk begins to accumulate meaningfully. NICE guidance on type 2 diabetes prevention (NG17) and cardiovascular risk (CG181) both identify the 40–74 age group as the primary target for proactive screening.

Blood tests give you something a GP appointment alone cannot: objective, quantified data about what is happening inside your body right now. Symptoms like fatigue, weight gain, and brain fog are non-specific. A blood panel distinguishes between low vitamin D, an underactive thyroid, insulin resistance, and low testosterone — conditions that feel similar but require completely different responses.

Getting a thorough baseline at 40 means that subsequent tests have something to compare against. Trends over time are often more informative than a single result. A cholesterol reading of 5.2 mmol/L means very little on its own; the same reading rising from 4.6 two years ago tells a clearer story.

What changes in your blood after 40

Several physiological shifts occur across the 40s that are directly measurable in blood. Understanding them helps explain why a more thorough panel — not just the basic NHS checks — is worth doing.

The NHS Health Check — what it covers and what it misses

The NHS Health Check is offered every 5 years to adults aged 40–74 who do not already have a diagnosed cardiovascular condition. It is free, delivered through GP practices, and focuses specifically on cardiovascular and diabetes risk. It is a valuable public health intervention — but it was designed as a population-level cardiovascular screen, not a personal health baseline.

Here is a side-by-side view of what it tests versus what a thorough private panel at 40 would include:

The NHS Health Check is worth doing — and if you have not had one, your GP surgery can arrange it. But waiting five years between checks at a stage of life when several risk factors can change quickly means that early shifts in thyroid function, vitamin status, or lipid profiles go undetected. A private panel alongside your NHS check fills those gaps.

The biomarkers every over-40 should test

The list below covers approximately 20 markers grouped by system. Not every person at 40 needs all of them immediately — a GP or clinician can advise on priorities based on your personal and family history. But each one has a clear rationale for inclusion in a baseline panel at this life stage.

Cardiovascular

• Total cholesterol, HDL, LDL, non-HDL cholesterol — the standard lipid panel. Non-HDL cholesterol (total minus HDL) is now preferred by NICE CG181 as a cardiovascular risk marker because it captures all atherogenic lipoproteins.
• Triglycerides — fasting triglycerides above 1.7 mmol/L are an independent cardiovascular risk factor and a useful signal for metabolic dysfunction. Target: below 1.7 mmol/L fasting.
• ApoB (apolipoprotein B) — counts the number of atherogenic lipoprotein particles directly. A more accurate predictor of cardiovascular events than LDL cholesterol in people with metabolic syndrome, insulin resistance, or high triglycerides. Optimal: below 0.8 g/L.
• Lp(a) (lipoprotein(a)) — a genetically determined lipoprotein that raises cardiovascular and aortic valve disease risk independently of LDL. Around 20% of the UK population carry levels above the high-risk threshold of 75 nmol/L. Lp(a) needs testing only once in adulthood as it changes little over time.
• hs-CRP (high-sensitivity C-reactive protein) — a marker of systemic inflammation. Below 1 mg/L is optimal; above 3 mg/L doubles cardiovascular risk independently of cholesterol, per the British Heart Foundation.

Metabolic

• HbA1c — average blood sugar over 2–3 months. The primary tool for diagnosing pre-diabetes (42–47 mmol/mol) and type 2 diabetes (48+ mmol/mol). Pre-diabetes affects an estimated 7 million people in the UK, most undiagnosed, and is reversible with lifestyle intervention, per Diabetes UK.
• Fasting glucose — a single-point measurement of blood sugar. Normal: below 5.5 mmol/L fasting. Used alongside HbA1c for a more complete metabolic picture; useful if HbA1c is borderline.
• Liver function tests (LFTs) — ALT, AST, GGT, ALP, albumin. Elevated liver enzymes can indicate non-alcoholic fatty liver disease (NAFLD), which affects roughly 1 in 3 UK adults and is strongly associated with insulin resistance. NICE NG49 recommends LFT screening in the context of metabolic risk.
• Kidney function (eGFR, creatinine) — estimated glomerular filtration rate indicates how efficiently your kidneys are clearing waste. Chronic kidney disease (CKD) is often asymptomatic until stages 3–4 and is more common in people with type 2 diabetes or hypertension.

Hormonal

• Testosterone + SHBG (sex hormone-binding globulin) — total testosterone alone can be misleading; free testosterone (calculated from total testosterone and SHBG) gives a more accurate picture of active hormone available to tissues. Relevant for both men experiencing fatigue or reduced libido and women with suspected androgen imbalance.
• Oestradiol + progesterone (women) — useful context for women in perimenopause or with irregular cycles, heavy bleeding, or mood changes. These fluctuate significantly across the cycle and over time, so a single reading should be interpreted carefully.
• TSH, free T4, free T3 (thyroid) — the NHS typically tests TSH alone. Adding free T4 and free T3 catches subclinical dysfunction that TSH alone may miss. Hypothyroidism is the most common undiagnosed condition in women over 40, per the NHS.
• FSH + LH (women aged 45+) — elevated FSH and LH in the context of missed periods and symptoms are the main biochemical indicators of perimenopause. Not needed for a basic screening panel but worth adding if symptoms suggest hormonal transition.

Nutritional

• Vitamin D (25-OH) — deficiency (below 25 nmol/L) is associated with bone loss, immune dysfunction, fatigue, and low mood. The NHS advises that most people in the UK are at risk of insufficiency during winter months, and recommends supplementation from October to March, per NHS guidance. Testing tells you whether supplementation is correcting the deficit.
• Vitamin B12 — deficiency causes fatigue, peripheral neuropathy, and cognitive effects. Absorption from food can decline with age as gastric acid production falls. More common in vegetarians, vegans, and people on metformin. Relevant NHS guidance: B12 and folate deficiency anaemia.
• Folate — works alongside B12. Deficiency causes megaloblastic anaemia and is particularly important in women considering pregnancy. Often tested together with B12.
• Ferritin + full iron studies — ferritin is the body’s iron storage protein. Low ferritin is the earliest sign of iron depletion, even before anaemia develops. Particularly relevant for premenopausal women. Full iron studies (serum iron, TIBC, transferrin saturation) give a more complete picture than ferritin alone, per NHS iron deficiency anaemia guidance.
• Magnesium — involved in over 300 enzymatic reactions. Serum magnesium is a crude measure (most magnesium is intracellular), but it identifies frank deficiency. Low dietary magnesium is extremely common and associated with muscle cramps, poor sleep, and insulin resistance.

Haematology

• Full blood count (FBC) — red cells, white cells, platelets, haemoglobin, MCV, MCH. The most frequently ordered blood test in the NHS and a useful baseline for detecting anaemia, infection, and haematological conditions. Should be part of every baseline panel.

Cardiovascular markers: ApoB, Lp(a), hs-CRP — the ones the NHS doesn’t routinely check

Standard NHS cholesterol testing measures total cholesterol, HDL, and calculated LDL. This is adequate for a basic population screen but it misses three markers that cardiologists increasingly consider more informative:

ApoB — the particle count the NHS doesn’t test

Every atherogenic lipoprotein particle — LDL, IDL, VLDL, Lp(a) — carries exactly one ApoB molecule. This means ApoB directly counts the number of particles that can lodge in arterial walls and initiate plaque. Two people with identical LDL cholesterol readings can have very different ApoB levels, and thus very different cardiovascular risk profiles. The European Atherosclerosis Society and the European Society of Cardiology now recommend ApoB as the preferred measure of atherogenic particle burden in their dyslipidaemia guidelines. Optimal ApoB is below 0.8 g/L.

Lp(a) — the genetic risk factor that affects 1 in 5

Lipoprotein(a) is a variant of LDL with an additional protein attached. Levels are largely genetically determined — lifestyle changes have minimal effect — and around 20% of people carry levels above 75 nmol/L, which significantly raises risk of cardiovascular events and aortic stenosis. Testing once in adulthood is sufficient, as levels remain stable over time. Because Lp(a) cannot be modified by statins or diet, a high reading changes the entire risk management strategy — prompting more aggressive LDL lowering and earlier preventive intervention.

Learn more in our detailed guide: Lp(a) blood test UK: what it means and what to do about it.

hs-CRP — inflammation as a cardiovascular risk factor

High-sensitivity CRP measures low levels of C-reactive protein, a liver-produced protein that rises with systemic inflammation. Chronic low-grade inflammation accelerates atherosclerosis independently of cholesterol. An hs-CRP below 1 mg/L is considered optimal for cardiovascular risk; above 3 mg/L roughly doubles the risk of a cardiovascular event. Above 10 mg/L typically indicates acute infection or a significant inflammatory condition that requires GP review. See: Inflammation blood test UK: what hs-CRP and ESR mean.

Metabolic health: HbA1c, fasting glucose, and insulin resistance

Type 2 diabetes does not appear overnight. It typically develops over 10–15 years through a silent pre-diabetes stage, during which blood sugar is elevated but not yet high enough for a formal diagnosis. This window is the most important one to catch — pre-diabetes is largely reversible with dietary and lifestyle change, while type 2 diabetes is a lifelong condition, per NHS type 2 diabetes guidance.

HbA1c measures the percentage of haemoglobin with glucose attached — a reflection of average blood sugar over the preceding 2–3 months. It is not affected by a single meal, which makes it a more stable measure than fasting glucose alone. The reference ranges are:

Fasting glucose adds value alongside HbA1c. It detects impaired fasting glucose (5.5–6.9 mmol/L), which can be present even when HbA1c is still in the normal range. Used together, the two markers give a more complete picture of metabolic health. The NICE NG17 guideline on type 2 diabetes prevention recommends intensive lifestyle programmes for people with pre-diabetes — but only for those who have been identified through testing.

For more detail, see: Pre-diabetes blood test UK: HbA1c, fasting glucose and what to do next and HbA1c blood test UK explained.

Hormonal shifts: testosterone, oestrogen, and thyroid

Testosterone in men

Testosterone in men declines at roughly 1–2% per year from the late 30s. For most men, this is gradual and causes few noticeable symptoms until levels fall more substantially. Symptoms of low testosterone — fatigue, reduced libido, difficulty maintaining muscle mass, low mood, and poor sleep — are non-specific and are frequently attributed to stress or ageing without investigation. Total testosterone, free testosterone (calculated), and SHBG together give a clear picture. See: Low testosterone symptoms in men: causes and next steps.

Oestrogen and progesterone in women

Perimenopause typically begins in the mid-40s and is characterised by fluctuating, then declining, oestrogen and progesterone. Symptoms — irregular periods, hot flushes, sleep disruption, mood changes, brain fog — overlap with thyroid dysfunction, iron deficiency, and low vitamin D. Testing helps distinguish the cause. A full hormonal panel for women around 40 might include oestradiol, progesterone, FSH, LH, testosterone, and SHBG. See: Menopause blood test UK: what to test and when.

Thyroid function

Hypothyroidism — an underactive thyroid — affects around 2% of the UK population, rising to approximately 5% of women over 60. It causes fatigue, weight gain, constipation, cold intolerance, and low mood, symptoms that are easy to attribute to other causes. NHS GPs typically test TSH (thyroid-stimulating hormone) alone. A private full thyroid panel adds free T4 and free T3, which can reveal subclinical hypothyroidism and conversion problems that a normal TSH does not capture. See: Thyroid blood test UK: what TSH, T4, and T3 mean.

Vitamins and minerals: D, B12, folate, ferritin, magnesium

Vitamin D

The UK’s latitude means that UVB exposure is insufficient for vitamin D synthesis for most of the year — roughly October through March. The NHS recommends that everyone consider supplementation during this period. Despite this, many people supplement without ever testing, meaning they may be correcting a deficit that does not exist — or not correcting one that does. Testing 25-OH vitamin D tells you your actual level. Deficiency is below 25 nmol/L; insufficiency is 25–50 nmol/L; the optimal range for most adults is 75–150 nmol/L. NICE PH56 provides guidance on supplementation in specific groups.

Vitamin B12

B12 deficiency causes fatigue, peripheral tingling, poor concentration, and, in severe cases, irreversible neurological damage. Absorption from food requires adequate gastric acid and a protein called intrinsic factor, both of which can decline with age. People on metformin for diabetes, those with coeliac disease, vegetarians, and vegans are at particular risk. Standard NHS testing measures serum B12, but active B12 (holotranscobalamin) is a more sensitive marker of functional deficiency.

Ferritin and iron

Iron deficiency is the most common nutritional deficiency worldwide. In the UK, it is most prevalent in premenopausal women due to menstrual blood loss. Low ferritin causes fatigue, hair loss, poor exercise tolerance, and difficulty concentrating — often well before haemoglobin falls and anaemia is detectable. Ferritin alone is not always sufficient; it rises during inflammation (as an acute-phase reactant), which can mask true deficiency. A full iron panel including serum iron, TIBC, and transferrin saturation gives a more accurate picture.

Magnesium

Magnesium is required for energy production, protein synthesis, muscle and nerve function, blood pressure regulation, and insulin signalling. Most magnesium is stored inside cells, making serum testing an imperfect measure, but it still identifies frank deficiency. Low dietary magnesium intake is very common in the UK, associated with high intake of processed food and low intake of vegetables, legumes, and nuts.

How often should over-40s test?

The right frequency depends on what was found in the baseline and on your personal risk profile. A useful general framework:

• Every year: HbA1c, cholesterol panel with ApoB, hs-CRP, vitamin D, full blood count, and ferritin for premenopausal women. Annual testing allows trends to emerge and interventions to be evaluated.
• Every 2–3 years: Full thyroid panel (unless symptomatic), liver and kidney function, B12 and folate, magnesium, testosterone/hormones if stable and asymptomatic.
• Once in adulthood: Lp(a). Levels are genetically determined and change minimally over time. One test is sufficient to establish whether you carry elevated risk.
• When symptomatic or following a lifestyle change: Any relevant marker. Starting a new diet, medication, or supplement warrants testing the markers it is designed to influence — otherwise you have no way of knowing whether it is working.

The NHS Health Check at every 5 years is the minimum floor, not the ceiling. For a more detailed testing schedule, see: How often should you have a blood test?

What to do with your results

A blood test result is data, not a diagnosis. The same number can mean different things in different people depending on age, sex, symptoms, medications, and family history. Here is how to approach your results practically:

• Read against the reference range, but also against optimal targets. A result can be within the laboratory reference range (usually the middle 95% of a population) but still suboptimal. Vitamin D at 32 nmol/L is ‘normal’ by many lab standards but insufficient for optimal bone and immune health.
• Look at patterns across related markers. A borderline HbA1c alongside high triglycerides, elevated ALT, and rising non-HDL cholesterol tells a clearer metabolic story than any single result alone.
• Share out-of-range results with your GP. Private blood tests do not replace NHS care. A GP may request repeat testing, refer to a specialist, or initiate treatment based on your results. Most GP surgeries will review private results alongside your NHS record.
• Track trends over time. The direction of change is often more informative than a single point. An HbA1c of 44 mmol/mol is pre-diabetic regardless of history. But an HbA1c of 44 mmol/mol that was 38 a year ago signals acceleration that needs attention.

For a plain-English primer on reading blood test reports, see: Blood test results explained: a practical guide.

How Helvy’s panels cover the over-40 essentials

Helvy’s blood testing panels are built around the markers with the strongest evidence base for adults at each life stage. The over-40 baseline panel includes the full lipid profile (with ApoB), HbA1c, full thyroid function, liver and kidney function, full blood count, vitamin D, B12, folate, ferritin, hs-CRP, and testosterone (or oestradiol depending on biological sex).

Tests are done at home using a finger-prick kit or small venous draw, processed by a UKAS-accredited laboratory, and results are reviewed by a GMC-registered clinician before being released to you — with plain-English explanations of what each result means and when to follow up with your GP.

Advanced add-ons for over-40s include Lp(a) (once-in-a-lifetime test), extended hormone panels for perimenopause or testosterone assessment, and cortisol for suspected HPA axis dysfunction. All results are stored in your account so trends are visible across tests over time.

Red flags that need GP attention

Some results from a private blood test require prompt GP follow-up rather than a wait-and-see approach. Contact your GP surgery within a few days if you see any of the following:

This list covers the most common critical findings in otherwise healthy over-40s. It is not exhaustive. If any result concerns you, your clinical team can advise on next steps. Helvy’s results include flagging for out-of-range markers and clinician notes on urgency.

Frequently asked questions

Sources

1. 01NHS Health Check programme
2. 02NICE CG181 — Cardiovascular disease: risk assessment and reduction
3. 03NICE NG17 — Type 2 diabetes prevention: population and community-level interventions
4. 04NHS — High cholesterol
5. 05NHS — Type 2 diabetes
6. 06NHS — Underactive thyroid (hypothyroidism)
7. 07NHS — Vitamin D
8. 08NHS — Vitamin B12 or folate deficiency anaemia
9. 09NHS — Iron deficiency anaemia
10. 10British Heart Foundation — Risk factors for cardiovascular disease
11. 11Diabetes UK — Pre-diabetes and risk factors
12. 12NICE PH56 — Vitamin D: supplement use in specific population groups