Blood test guides · UK

Your results, in plain English.

Your blood test came back with numbers. These guides explain what they actually mean: written for UK patients, grounded in NHS and NICE guidance, without the jargon.

Start here: reading your results

Getting started10 min read Blood test results explained: a plain English guide for UK patients What do the columns mean? What are reference ranges? Why does normal sometimes feel wrong? A complete guide to reading your results. → Getting started8 min read How to read blood test results: units, ranges and flags explained H and L flags, mmol/L versus g/L, reference ranges that vary by lab. A practical guide to making sense of what is on the page. → NHS results8 min read NHS blood test results explained: what your GP sees and what you don't NHS results often arrive with little explanation. What your GP is looking at, what the flags mean, and which questions are worth asking. →

Blood sugar & metabolic health

HbA1c7 min read HbA1c normal range UK: what your result actually means The NHS uses 48 mmol/mol as its diabetes threshold. Here is what your number means if you sit below it, and what counts as prediabetes. → Cholesterol8 min read Cholesterol levels explained: total, LDL, HDL and triglycerides Your cholesterol result is four numbers, not one. What each one means, and why the ratio matters more than the total. →

Iron & energy

Ferritin7 min read Ferritin levels UK: what's normal, what's low, and what to do Ferritin is your iron store, not the same as iron itself. The NHS range is wide, and many people feel symptoms well before they hit the floor. → Ferritin6 min read Low ferritin symptoms: why you feel tired when your result is "normal" Fatigue, hair loss, brain fog: low ferritin can cause all of these even when your result sits within range. Here is why. → Ferritin · Iron5 min read Low ferritin with normal haemoglobin: what it means and what causes it If you've received blood test results showing low ferritin but normal haemoglobin, you might be wondering what this combination means. →

Vitamins & deficiencies

Vitamin D7 min read Vitamin D deficiency symptoms UK: what your blood test shows Over 1 in 5 UK adults are vitamin D deficient. What the numbers mean, which symptoms to expect, and when supplementing makes sense. → Vitamin D6 min read Vitamin D blood test results: reading your 25-OH-D level Your vitamin D result is reported as 25-hydroxyvitamin D. What the number means, what the NHS considers deficient, and what optimal looks like. →

Hormones & conditions

PCOS9 min read PCOS blood test results: what to look for and what the ranges mean PCOS diagnosis involves several markers: LH, FSH, testosterone, AMH and insulin. How to read each one, and what the pattern means together. →

Beyond the guides

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