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Vitamin B9 (Folic Acid) Test £39.95
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Vitamin B9 (Folic Acid)

What is Vitamin B9?

Vitamin B9, also known as folic acid or folate, is one of the eight B vitamins. This vitamin naturally occurs in some foods, can be added to food products, and can be provided as a dietary supplement. It is also made by bacteria in your colon (large intestine). Folate is naturally present in many foods, and folic acid is added to some foods. Use of the terms Vitamin B9, folic acid, and folate varies on food and supplement labels; vitamin B9 covers naturally occurring folates in food, and both folates and folic acid in dietary supplements and in fortified foods.

Vitamin B9 in food, is broken down during digestion and absorbed in the gut. About half of the body's Vitamin B9 is stored in the liver, while the rest is found in the blood and tissues.

Buy a Vitamin B9 test online

Click on the link below to proceed with your test request.

Vitamin B9 (Folic Acid) Test £39.95

Results are available within 24 hours of your sample arriving in the laboratory, along with an interpretation from a doctor. The kit includes a reply-paid RM24 Tracked envelope to ensure a speedy and trackable return.

Why is Vitamin B9 important?

Vitamin B9 is needed for good health. Vitamin B9 is required in the body to make the genetic material including DNA within your cells, and for cell division.

Vitamin B9 deficiency may have a role in certain disorders, including cardiovascular disease, dementia, depression, an autistic spectrum disorder, cancer, and birth defects.

What are the symptoms of Vitamin B9 deficiency?

People with a vitamin B9 deficiency may have symptoms such as fatigue, weakness, headache, irritability, breathlessness, poor concentration, heart palpitations, ulcers in the mouth, gut problems, and colour changes in skin, nails and hair. Blood test results may suggest a blood disorder called megaloblastic anaemia in which red blood cells are larger in size and fewer in number than normal. A deficiency in vitamin B9 in women who are pregnant increases the risk of problems with the growth and development of their babies, such as neural tube defects, low birth weight, and premature birth.

What are the effects of too much Vitamin B9?

Taking many folate supplements can mask a deficiency in vitamin B12, which also causes anaemia and damages the nervous system; folate supplements can normalise anaemia but not any nervous system damage and can worsen vitamin B12 deficiency symptoms. Studies have also suggested that high vitamin B9 doses might increase the risk of some types of cancers, including colorectal cancer.

While folate that naturally occurs in food is not harmful, excess from folate supplements or fortified foods should be avoided. The upper limit for folate intake in children aged 1-13 years ranges 300-600 micrograms, in teenagers aged 14-18 years is 800 micrograms, and in adults is 1000 micrograms.

Who should have their Vitamin B9 tested?

Some people are more likely to get enough vitamin B9 than others, who either get too little or too much.

A deficiency in vitamin B9 may occur in:

  • People with alcohol use disorder, because they often have poor diets
  • Women of childbearing age or who are pregnant
  • People with a disorder causing poor absorption of vitamin B9, such as inflammatory bowel disease, and coeliac disease
  • People who have low stomach acid levels, such as with atrophic gastritis (thinning of the stomach lining)
  • After surgery of the stomach
  • People, particularly Hispanics, with a variant in the MTHFR gene that results in a reduction in the amount of folate converted to an active form.

Excess vitamin B9 intake may occur through excessive or unnecessary vitamin B9 supplementation, particularly in:

  • Older people, who will most often take dietary supplements above the recommended daily limit
  • Children aged 1-13 years, who take folic acid-containing supplements plus have fortified foods, and/or take dietary supplements exceeding the recommended daily limit.

How to test for Vitamin B9?

Before doing the vitamin B9 (folic acid) test, it is important to tell your doctor if you are taking any dietary supplements containing folic acid. You may be advised to stop them and wait a few weeks before doing the test, as the test results will not reflect your true folic acid/folate levels.

A test for vitamin B9 can be done from a blood sample taken in your home. A self-collection pack, complete with full instructions on how to take and collect a sample of blood, is provided by The Online Clinic. Carefully following the instructions; several drops of blood are taken from your little finger and collected in a collection tube. The blood sample is then posted to the laboratory for analysis. Test results are sent to your doctor at The Online Clinic who will then interpret the findings for you.

What do Vitamin B9 test results indicate?

Values reflecting normal vitamin B9 levels vary depending on your age and the laboratory analysing your blood sample. Most people get the folic acid/folate they need through eating a healthy balanced diet. However, your test result will show whether you have a folate/folic acid deficiency, whether you need a dietary supplement, or whether your dietary supplementation is providing too much folate/folic acid.

You should tell your doctor the medicines that you are taking, including any dietary supplements. Supplements can interact with some medicines, such as methotrexate, antiepileptic medications, and sulfasalazine, reducing the effects of the medicine and/or levels of folate.

What is a normal daily intake of Vitamin B9?

Use of the terms Vitamin B9, folic acid, and folate varies. Folate is naturally present in many foods, and folic acid is added to some foods. The body absorbs more folic acid from dietary supplements and fortified foods than from folate occurring naturally in foods. Therefore, less folic acid is needed to achieve the Recommended Dietary Allowance (or RDA), and the RDA is measured in micrograms (mcg) dietary folate equivalents (DFE).

The Recommended Dietary Allowance (or RDA) is the average daily level of nutrient intake sufficient to meet the requirements of almost all healthy people, while an Adequate Intake should provide all a body's nutritional needs.

The RDA of folate varies according to a person's age. Thus, from:

  • Birth to 6 months, 65 mcg DFE (Adequate Intake)
  • 7-12 months, 80 mcg DFE
  • 1-3 years, 150 mcg DFE
  • 4-8 years, 200 mcg DFE
  • 9-13 years, 300 mcg DFE
  • 14 years and older, 400 mcg DFE
  • During pregnancy, 600 mcg DFE
  • During breastfeeding, 500 mcg DFE

How to maintain or achieve good Vitamin B9 levels

Folate is found in a wide range of foods so you can achieve the recommended amount by eating a varied diet. Folate is naturally found (particularly) in meat (beef liver), vegetables (green leafy vegetables, e.g., spinach, asparagus, Brussel sprouts and broccoli), fruits and fruit juices (tomato, orange, banana), grains, nuts, peas and beans. Folic acid is generally added to grain products, e.g., breakfast cereals and flour-containing products, such as bread, pasta, rice and corn. You can see if a food has been 'fortified' or 'enriched' with folic acid by checking the food label.

Dietary supplements that contain folic acid include multivitamins and prenatal vitamins, and supplements containing other B-complex vitamins or folic acid only. Some dietary supplements contain the folic acid breakdown product 5-MTHF, which may be better absorbed by people with the called MTHFR gene variant.

Reviewed by: Dr Loraine Haslam MBBS, DRCOG, DFSRH, LoC SDI, LoC IUT, MRCGP
GMC registration number: 4524038
Date: 27 March 2023
Next review: 26 March 2025
All UK registered doctors can have their registration checked on
The Medical Register at the GMC website.
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