Vitamin C Test
Below is a plain-language overview of the vitamin c test. A vitamin C test measures the amount of vitamin C (ascorbic acid) in your blood. It is usually ordered when a doctor suspects a deficiency or wants to check if you are getting enough of this nutrient.
- Sample type
- blood
- Category
- Vitamin & Mineral
- Turnaround
- 1-3 business days
- Price
- $49
- Referral
- Not required
A vitamin C test measures the amount of vitamin C (ascorbic acid) in your blood. It is usually ordered when a doctor suspects a deficiency or wants to check if you are getting enough of this nutrient.
What it measures
- Vitamin C (ascorbic acid) level — The main measurement; shows how much vitamin C is in your blood at the time of the test.
- Plasma ascorbate — Another term for the same measurement, often used in lab reports.
- Leukocyte vitamin C (rarely) — A less common measure that reflects vitamin C stored in white blood cells, but it is not routinely used.
Who it is for
Doctors typically order this test for people with symptoms of vitamin C deficiency, such as easy bruising, bleeding gums, or poor wound healing, or for those with conditions that affect nutrient absorption.
Preparation
Fasting is not required for a vitamin C test. You can eat and drink normally before the blood draw, but tell your doctor about any vitamin supplements you take.
Results and what they mean
Results are reported as a number that shows the level of vitamin C in your blood. Your clinician will interpret this number along with your symptoms and medical history. This information is general and not a substitute for medical advice.
How to order this test
- Choose the test and place a confidential order online.
- Select a certified collection site and pick a time that suits you.
- Have your specimen collected — most draws take only a few minutes.
- Review results in a secure portal, typically within 1–3 days.
Preparation, hours, and pricing vary by site; confirm details directly with the lab before your visit.
Availability by state
Direct-access online ordering for the vitamin c test is available in most states. It is currently unavailable in 6 states:
Everywhere else you can order confidentially and collect your sample at a certified site. Browse by state →
Frequently asked questions
Do I need to fast for this test?
No, fasting is not needed. You can eat and drink as usual before the blood draw.
How long does it take to get results?
Results are usually available within 1 to 3 business days.
What can affect my vitamin C level?
Recent vitamin C supplements, smoking, and certain medical conditions can affect your level. Tell your doctor about any supplements you take.
Is this test covered by insurance?
Coverage depends on your insurance plan and the reason for the test. Check with your insurance provider.