Blood test guides

Understanding your results,
in plain English

Your blood test came back with numbers. Here's what they actually mean — written for UK patients, grounded in NHS and NICE guidance, without the jargon.

Blood sugar & metabolic health
HbA1c
HbA1c normal range UK: what your result actually means
The NHS uses 48 mmol/mol as its diabetes threshold — but what does your number mean if you're below it, and what counts as prediabetes?
7 min read→
Cholesterol
Cholesterol levels explained: total, LDL, HDL and triglycerides
Your cholesterol result is four numbers, not one. Here's what each one means and why the ratio matters more than the total.
8 min read→
Iron & energy
Ferritin
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 reference range is wide, and many people feel symptoms well before they hit the floor.
7 min read→
Ferritin
Low ferritin symptoms: why you feel tired even when your result is "normal"
Fatigue, hair loss, brain fog — low ferritin can cause all of these even when your GP says your result is within range. Here's why.
6 min read→
Vitamins & deficiencies
Vitamin D
Vitamin D deficiency symptoms UK: what your blood test shows
Over 1 in 5 UK adults are vitamin D deficient. Here's what the numbers mean, what symptoms to expect, and when supplementing makes sense.
7 min read→
Vitamin D
Vitamin D blood test results: reading your 25-OH-D level
Your vitamin D result is reported as 25-hydroxyvitamin D. Here's what the number means, what the NHS considers deficient, and what optimal looks like.
6 min read→
Hormones & conditions
PCOS
PCOS blood test results: what to look for and what the ranges mean
PCOS diagnosis involves several markers — LH, FSH, testosterone, AMH and insulin. Here's how to read each one and what the pattern means together.
9 min read→
Reading your results
Getting started
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.
10 min read→
Getting started
How to read blood test results: units, ranges and flags explained
H and L flags, mmol/L vs g/L, reference ranges that vary by lab — here's a practical guide to making sense of what's on the page.
8 min read→
NHS results
NHS blood test results explained: what your GP sees and what you don't
NHS results often arrive with little explanation. Here's what your GP is looking at, what the flags mean, and what questions are worth asking.
8 min read→

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