Blood WorkThe vitamin deficiencies a blood test checks most often are vitamin D (25-hydroxy vitamin D), vitamin B12 and folate, usually alongside ferritin for iron. Testing makes sense when you have symptoms or a risk such as a restricted diet, weight-loss surgery or certain medicines. At Passion Health, the $119 Energy & Iron Panel covers B12, folate and iron with a blood count and thyroid; vitamin D is $40, with no extra fee when added to a panel.
What to know about vitamin deficiencies
Most people who eat a varied diet get enough vitamins, and many deficiencies cause no symptoms until they're well advanced. When symptoms appear they're often vague: tiredness, weakness, low mood or poor concentration.
Some are more specific. Low B12 can cause numbness or tingling in the hands and feet, balance problems, memory changes and anemia, and the nerve damage can become permanent if it's left untreated. Low folate also causes anemia. Very low vitamin D can cause bone pain and muscle weakness, and over years it contributes to weak bones.
Who should get tested?
Vitamin B12: a vegan or mostly vegetarian diet, older age, long-term metformin or acid-reducing medicine, weight-loss surgery, celiac or Crohn's disease, or numbness, tingling or unexplained anemia.
Folate: heavy alcohol use, a very limited diet, celiac disease, or medicines such as methotrexate.
Vitamin D: osteoporosis or a fracture from a minor fall, malabsorption or weight-loss surgery, kidney or liver disease, or medicines that affect vitamin D, such as some seizure medicines and long-term steroids.
Routine vitamin D testing isn't recommended for healthy adults without a reason. The US Preventive Services Task Force found too little evidence for screening, and the Endocrine Society's 2024 guideline suggests against routine testing in healthy adults of any age. For adults 75 and older it suggests a daily supplement without testing first.
Which tests check for vitamin deficiencies?
| Test | What it shows | Where it's included |
|---|---|---|
| Vitamin D, 25-hydroxy | Your vitamin D stores from sun, food and supplements. | Single test $40, added to any panel with no extra fee. |
| Vitamin B12 | Your B12 level. A borderline result may need a follow-up test (methylmalonic acid) to confirm. | Energy & Iron $119. Alone $30. |
| Folate | Your folate level. | Energy & Iron $119. Alone $20. |
| Ferritin and iron | Iron stores and iron in your blood; iron deficiency is the most common nutrient deficiency worldwide. See the anemia and iron guide. | Energy & Iron $119. Ferritin alone $15. |
| Blood count (MCV) | Large red cells point to low B12 or folate. | Essential $59, Energy & Iron $119. Alone $20. |
What your results mean
| Test | What the result means |
|---|---|
| Vitamin D | Below 12 ng/mL is clearly deficient. The National Academy of Medicine considers 20 ng/mL enough for bone health in most people; some labs flag anything under 30 ng/mL, and experts disagree about the 20 to 30 range. |
| Vitamin B12 | Below about 200 pg/mL is low. Between about 200 and 300 pg/mL is borderline, and a methylmalonic acid test can show whether your body is short. |
| Folate | Your lab's range applies. Low folate and low B12 can look alike on a blood count, so both are checked together. |
Tip: biotin (vitamin B7) supplements can distort some lab tests. Tell your clinician if you take biotin; you may be asked to pause it for a few days before your draw.
What these tests can't tell you
A normal level doesn't prove your symptoms aren't vitamin-related, and a low level doesn't prove it caused them; your clinician weighs both. Blood levels also don't show why you're low. For B12, the cause can be pernicious anemia, an autoimmune condition that needs its own tests and lifelong treatment.
If your results are off at Passion Health
A Texas-licensed clinician reviews every result. If a level is low, we:
- explain whether the result fits your symptoms;
- recommend the right dose and form, for example B12 tablets or injections, or vitamin D matched to your level;
- look for the cause when a level is very low, such as absorption problems or medicines;
- recheck in about three months when the result changes your treatment.
Care online: neuropathy, foot numbness, brain fog and osteoporosis.
Vitamin test cost in Texas
Self-pay. The Energy & Iron Panel ($119) covers B12, folate, ferritin and iron, plus a blood count, thyroid and the metabolic panel, with the draw and a clinician's review. Add vitamin D for $40 with no extra fee: $159 for all four nutrients. Single tests are vitamin D $40, B12 $30 or folate $20, plus one $29 draw and review fee per order.
With insurance. If we're in network with your plan, we bill it when the test is covered. You pay cash for a test only after we tell you the price in writing, and Medicare patients sign an Advance Beneficiary Notice first.
Vitamin deficiency test questions
What blood test checks for vitamin deficiencies?
There's no single vitamin panel; each vitamin is its own test. The common ones are 25-hydroxy vitamin D, vitamin B12 and folate, usually with ferritin for iron and a blood count.
Should I get my vitamin D checked?
Only if you have a reason: bone loss or a fracture, malabsorption, kidney or liver disease, or medicines that affect vitamin D. Routine testing isn't recommended for healthy adults (Endocrine Society, 2024).
What vitamin D level is too low?
Below 12 ng/mL is clearly deficient, and most experts consider 20 ng/mL or higher enough for bone health. Some labs flag anything under 30 ng/mL.
What are signs of B12 deficiency?
Tiredness, pale skin, numbness or tingling in the hands and feet, balance problems, a sore tongue and memory changes. Nerve symptoms can become permanent if B12 stays low, so they're worth checking promptly.
Do I need to fast for a vitamin test?
Vitamin D, B12 and folate don't need fasting. The Energy & Iron Panel includes a metabolic panel, so fast 8 to 12 hours before that draw; water is fine.
Should I stop my vitamins before the test?
Keep taking them unless your clinician says otherwise, so the result shows your usual level. The exception is biotin, which can distort some tests; ask whether to pause it for a few days.
Sources
- Endocrine Society: Vitamin D for the Prevention of Disease, Clinical Practice Guideline, 2024
- US Preventive Services Task Force: Vitamin D Deficiency in Adults, Screening, 2021
- NIH Office of Dietary Supplements: Vitamin B12, Health Professional Fact Sheet
- NIH Office of Dietary Supplements: Vitamin D, Health Professional Fact Sheet