The B vitamins are all crucial for cell metabolism, normal functioning of the central nervous system and the formation of red blood cells. This test measures the level of vitamin B3 in your blood.
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Vitamins
Vitamin B3
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The B vitamins are a group of 8 all water-soluble vitamins, all crucial for cell metabolism, converting food into energy, the normal functioning of the central nervous system and the formation of red blood cells.
Special instructions
How to prepare for your test
Prepare for your Vitamin B3 (Niacin) Blood Test by following these instructions. Do not eat or drink anything other than water for 12 hours prior to your test. If you take medication then you are allowed to take it as you would normally. Take your sample at least 24 hours after any vitamin or mineral supplements.
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FAQs
What is vitamin B3?
Vitamin B3 is in foods such as eggs, peanuts, fresh fruit and vegetables, red meat, and fortified cereals.
What are the symptoms of vitamin B3 deficiency?
Although extremely rare, vitamin B3 deficiency can occur. Symptoms include fatigue, vomiting, disorientation, memory loss, and mouth swelling. Strict vegetarians and vegans may be at risk of vitamin B3 deficiency.
How many B vitamins are there?
Altogether, there are eight B vitamins, each with its purpose and role within the body. The B vitamins are all water-soluble and crucial for cell metabolism, normal functioning of the central nervous system, and the formation of red blood cells. All the B vitamins we need should be available through our diet. The B vitamins help to convert food into fuel and metabolise fats and proteins.