Nutrition & Vitamins
Nutritional deficiencies are the most common — and most overlooked — cause of fatigue, low mood and poor immunity. A blood test shows you exactly what’s missing.
Nutritional Testing
Most people taking supplements are guessing. They buy what the marketing says, not what their body actually needs. A nutritional blood test tells you exactly where your deficiencies lie — so you can supplement precisely, not randomly.
Deficiency Symptoms We Investigate
Persistent fatigue and low energy
Brain fog and difficulty concentrating
Frequent infections and poor immunity
Hair loss and brittle nails
Low mood and seasonal depression
Featured Test
A targeted nutritional blood test covering the key vitamins and minerals your body depends on. Find out exactly where you stand — and what to do about it.
Nutrition Tests
From single-marker checks to our comprehensive metabolic and nutrient profile.
Blood Test
A targeted nutritional panel covering the key vitamins and minerals your body depends on. Precise, actionable and easy to understand.
Blood Test
20 key biomarkers covering iron, vitamins, kidney and liver function — a smart first step.
Blood Test
Iron, ferritin, zinc, selenium, vitamins and thyroid — everything that affects how you look.
Blood Test
Full thyroid panel: TSH, Free T3, Free T4 — the hormones that drive energy and metabolism.
Blood Test
Our most comprehensive profile — 70+ biomarkers for total health clarity.
Key Nutrients
In the UK, these three deficiencies account for the majority of fatigue, mood and immune complaints we test for.
The UK’s most common deficiency. Optimal levels (75–200 nmol/L) are associated with better immune function, mood, muscle health and reduced cancer risk. Testing is the only way to know your level — and the right dose to supplement.
Iron deficiency without anaemia is widely underdiagnosed — particularly in women and athletes. Low ferritin causes fatigue, hair loss and brain fog even when standard iron markers appear normal.
B12 deficiency develops slowly and is often attributed to stress or ageing before the blood picture is checked. Vegans, those on metformin and people with gut issues are particularly at risk.
Choose Your Path
I’m not sure
Tell us your symptoms and diet and we’ll point you toward the most relevant nutritional markers to investigate.
Find My TestI know what I need
Book your nutritional blood test online. Same-day results. Expert-reviewed report.
View All TestsCommon Questions
What Our Clients Say
Outstanding service from start to finish. They consistently go above and beyond expectations.
Alex, Google ⭐⭐⭐⭐⭐
Very impressed with the amount of markers checked especially for the price. Speedy delivery and super speedy results and just an overall great experience. Will continue to use Youth Revisited.
Verified Customer, Google ⭐⭐⭐⭐⭐
Had been with Medichecks for 9 years, tried Youth Revisited for a change and find them much more personal to deal with. The results are in a much better format and easy to understand.
Verified Customer, Google ⭐⭐⭐⭐⭐
