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Vitamin B3 (Nicotinamide)
88.00
This test measures Vitamin B3 (Nicotinamide) levels linked to energy production and cellular repair. Deficiency can affect skin, nerves, and metabolism.
Turnaround time
8 days
Biomarkers count
1
Same-Day Appointments
UKAS Accredited Labs
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Under 18? Patients under 18 can only be seen at GB Medlabs and Clinilabs, Monday to Friday only.
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Details about Vitamin B3 (Nicotinamide)
What is a Vitamin B3 test?
A Vitamin B3 test measures the level of nicotinamide (niacin) in your blood. Vitamin B3 is essential for converting food into energy and is a key component of NAD/NADH, which are vital for cellular metabolism and repair.
It also supports skin health, nerve function, brain health, and DNA repair processes.
Why do I need a Vitamin B3 test?
Vitamin B3 deficiency can present with fatigue, skin issues, brain fog, and digestive problems, often without obvious cause.
Reasons for testing include:
• Persistent fatigue
• Brain fog or poor concentration
• Skin rashes or sensitivity to sunlight
• Digestive discomfort
• Poor diet or malabsorption
• High stress levels
• Neurological symptoms
Benefits of the test
1. Assesses cellular energy metabolism
2. Helps explain fatigue and brain fog
3. Supports skin and nerve health assessment
4. Important for DNA repair and recovery
5. Detects hidden nutritional deficiency
6. Linked to NAD/NADH metabolic pathways
7. Useful in digestive or absorption issues
8. Guides precise supplementation
Expanded benefit explanation
Vitamin B3 is central to energy production and cellular repair. Identifying deficiency allows correction of symptoms affecting energy, cognition, and skin health.
Step-by-step — How testing works
We offer two UK-wide testing options:
Clinic testing
• Choose nearest UK clinic
• Blood sample collected
• Laboratory analysis performed
• Results securely returned
Home visit (+£60)
• Phlebotomist visits you
• Blood sample collected safely
• Sample sent to lab
• Results delivered confidentially
Your results explained
Low levels
May indicate poor diet, malabsorption, or increased metabolic demand.
Normal levels
Indicates adequate Vitamin B3 status.
High levels
Usually due to supplementation.
How It Works
Simple steps to get your results
1
Book Online
Choose your test online and book in seconds. Select your preferred clinic location or home visit option.
2
Visit or Test at Home
Attend one of our UK or London clinics, arrange a home nurse visit, or use a finger-prick kit where available.
3
Get Your Results
Your sample is analysed by accredited UK laboratories, with secure results delivered directly to you.
Take control of your health with London Blood Tests
WhatsApp UsHow to Prepare for Your Test
Follow these guidelines for accurate results
Sample Timing
Where possible, attend your blood test between 7am and 12pm. Please wait until any short-term illness or infection has fully resolved before testing. Avoid intense exercise for 24–48 hours beforehand, as this can affect certain markers.
Fasting & Hydration
Fasting is not always required, but some tests may recommend it. If fasting is advised, avoid food for 8–12 hours before your appointment and drink water only. Stay well hydrated, as this helps with sample collection and accuracy.
Medications & Supplements
Continue prescribed medications unless advised otherwise by your clinician. Avoid vitamin, mineral, or biotin supplements for at least 24–48 hours before your test, as these can interfere with results. If you are unsure about any medication or supplement, please let us know before your appointment.
Hormones & Menstrual Cycle
For hormone-related tests, timing within your menstrual cycle may be important. If relevant, follow any specific guidance provided on your test page.
If you have any questions or special circumstances, our team is happy to advise before your appointment.
Frequently Asked Questions
It measures plasma nicotinamide, the main circulating form of vitamin B3.
No fasting is required.
Avoid taking high-dose B vitamins on the morning of your test unless medically advised.
Fatigue, irritability, poor memory, cracked skin, digestive discomfort, or sun-sensitive rashes.
Results are available in 1–3 business days.
Yes. Nicotinamide plays a role in skin barrier repair and inflammation reduction.
Yes — a phlebotomist can attend your home or hotel to collect your sample.
Poor diet, alcohol use, malabsorption, chronic illness, stress, or high metabolic demand.
Supplementation and dietary adjustments can correct deficiency quickly. Our GP can provide a tailored plan.
No. This measures vitamin B3 concentration, not NAD metabolites — though B3 status influences NAD⁺ production.
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