Why Private MD Labs?
90-day money-back guarantee Lab order in minutes Save a trip to the doctor Low prices since 2005 Labs within 2 miles
Sample image
Sample report
Vitamin B12 test for individuals experiencing fatigue, low energy, and nutritional deficiencies

Blood Test for Fatigue and Low Energy (Vitamin B12)

Vitamin B12

Google
3,141 reviews
  • Pinpoint the cause of your fatigue
  • Reveal hidden vitamin B12 deficiencies
  • Enhance your energy levels effectively
First results as soon as overnight*

90 day happiness guarantee

We stand behind our service

Prescription & fees included

Go directly to the lab, no extra fees

Easy to understand results

With friendly doctor's notes & guidance

Fast & convenient

Lab visit as quick as 10 mins in & out

90 day happiness guarantee

We stand behind our service

Prescription & fees included

Go directly to the lab, no extra fees

Easy to understand results

With friendly doctor's notes & guidance

Fast & convenient

Lab visit as quick as 10 mins in & out

What's this test for?

This test is ideal if you're experiencing persistent fatigue, weakness, or low energy that doesn't improve with rest. It helps identify vitamin B12 deficiencies that can affect your energy levels, mood, cognitive function, and overall well-being. Many people use this test when they suspect nutritional deficiencies might be behind their tiredness or when they have dietary restrictions that limit B12 intake.

How should I prepare for this test?

No fasting is needed for this test, making it convenient and easy to fit into your schedule. You can eat and drink normally before your blood draw. Just schedule your appointment at a lab near you and get tested at your convenience.

What's included in this test?

Vitamin B12

This test measures your Vitamin B12 levels to assess your nutritional status and identify potential deficiencies. B12 is essential for energy production, red blood cell formation, and nervous system function, which is why low levels can cause fatigue, weakness, and cognitive issues. This test is particularly valuable for diagnosing pernicious anemia, evaluating digestive absorption problems, and monitoring overall nutritional health.

What happens after I get my results?
You'll receive detailed doctor notes in simple language explaining what your vitamin B12 levels mean for your energy, brain function, and overall health. These notes include personalized recommendations like dietary changes, supplement suggestions, or whether you should investigate absorption issues further. You'll also get the standard lab report and can track your B12 levels over time using our trends feature to see how your diet or supplements are working.
Who should consider getting this test?
This test is particularly important for vegetarians and vegans who may not get enough B12 from their diet, older adults who have reduced absorption, and people with digestive disorders like Crohn's disease or celiac disease. It's also useful for anyone taking certain medications like metformin or proton pump inhibitors that can interfere with B12 absorption, or anyone experiencing unexplained fatigue and weakness.
What symptoms indicate I may need this test?
Common signs of B12 deficiency include persistent fatigue or weakness, tingling or numbness in hands and feet, difficulty concentrating or memory problems, and pale or yellowish skin. You might also experience mood changes, balance issues, or a sore tongue. If you have any of these symptoms, especially combined with dietary restrictions or digestive issues, testing your B12 levels can provide important answers.
How can I naturally support my vitamin B12 levels?
B12 is naturally found in animal products, so include more fish, meat, poultry, eggs, and dairy in your diet if you eat these foods. If you're vegetarian or vegan, look for B12-fortified foods like plant-based milks, breakfast cereals, and nutritional yeast. For those with absorption issues or confirmed deficiency, B12 supplements or sublingual tablets may be necessary since dietary changes alone might not be enough.
What is vitamin B12 and why does it matter?
Vitamin B12, also called cobalamin, is an essential nutrient your body needs to produce red blood cells, maintain your nervous system, and create DNA. Your body can't make B12 on its own, so you must get it from food or supplements. It's crucial for energy production, brain function, and preventing anemia, which is why deficiency can cause such significant fatigue and neurological symptoms.
What does low vitamin B12 mean?
Low B12 levels indicate your body isn't getting enough of this essential vitamin, either from diet, poor absorption, or certain medical conditions. This can lead to pernicious anemia, fatigue, weakness, nerve damage, and cognitive problems if left untreated. Common causes include strict vegan diets, digestive disorders, gastric surgery, or long-term use of certain medications.
How often should I retest my vitamin B12?
If you're starting B12 supplements or making dietary changes, retest in 2-3 months to ensure your levels are improving. Once your levels are optimal, annual testing is typically sufficient for monitoring unless you have ongoing absorption issues or dietary restrictions. If you have pernicious anemia or digestive disorders, your doctor may recommend more frequent testing every 3-6 months.
How’s this work?
Getting your blood test with us is easy, private & backed by the power of science.

Long story short:
  1. In the test options, use the filters or search box to narrow your choices and find the test you want.
  2. If you need a hand navigating through options, text our super friendly support team at 754-799-7833, and we'll provide tailored suggestions to help you find the ideal test.
  3. Once your order is placed, we’ll create your doctor’s lab order remotely, without any need for you to make a trip to a doctor in person or to talk to the doctor. Expect to receive your doctor’s lab order right in your inbox. It will also be in your patient portal if you need to find it later. We’ll also include instructions regarding fasting and other requirements for your test. Your patient portal will be auto-created hassle-free during checkout.
  4. If this is your first time ordering, you'll be prompted to create a password for instant login access to your patient portal. It's a quick way to conveniently access your orders and results whenever you want.
  5. When you’re ready, visit one of our 4,000 locations. Just bring your ID – no printing or faxing of your lab order is needed, as your order and details will already be in the lab system.
  6. Note that most lab locations don’t accept walk-ins, so it’s best to book an appointment in advance. Don’t worry – we’ll provide detailed instructions along the way.
  7. You’ll get your results via email & SMS and dive into understanding your body better. Yup, that easy!
  8. If you have any questions, please text us at 754-799-7833 or email [email protected] and we'll gladly help you.
How do I know which test to get?
In the test options, find the test you want. If you’re not sure which test to get, we can lend a hand in finding the right option.

Just text or call us at 754-799-7833, email us at [email protected], and we'll gladly help you. We've got your back and reply quickly.
Is it possible to make changes to my lab order if I made a mistake with the name, date of birth, or any other details?
Absolutely! We totally understand that errors can happen. No worries, we're here to help you.

Just reach out to us via text at 754-799-7833 or shoot us an email at [email protected]. Remember to include your order number and let us know the correct information you’d like to update. Our awesome team will jump right in and make sure everything is sorted out and accurate for you.

There are no changes necessary if your address is wrong on the requisition though. We don’t mail anything out.

Our lab requires an address to be listed to generate an order.
Do you accept health insurance?
Only HSA & FSA is accepted.

Our services are strictly self-pay and cannot be submitted to your health insurance provider except for Health Savings Accounts or Flexible Savings Accounts.

This policy applies to all insurance companies, including federal health insurance programs like Medicare.

If you have any questions, please text us at 754-799-7833 or email [email protected].
Can I cancel my order?
Yes.

We get it – sometimes your needs change.

As long as your samples haven’t been collected yet, we’re happy to help you cancel your order.

If you have any further questions, please text us at 754-799-7833 or email [email protected].

You can read more about our cancellation policy here.
How can I find a lab location near me?
During the ordering process, you’ll be able to select a specific lab near you, with no strings attached! You can switch it up later easily and visit any of our authorized locations as long as it’s the same lab company you selected your test for (Quest Diagnostics or Labcorp).

Before you proceed with your order, feel free to browse through all our lab locations here. This will give you the peace of mind of knowing that there's a lab nearby your home, office or your favorite gym.

If you have any questions, please text us at 754-799-7833 or email [email protected] and we'll gladly help you.

Here’s why 1,000,000+ customers chose us for affordable hassle-free private blood testing.

You get clinical lab reports & simplified health insights.
Save time & gas, go straight to the lab. Our doctors cover the rest.
Results start landing the next day after your lab visit.*
We don’t sell or share your data. Your time & privacy matter.
US-licensed doctors have your back if things get unclear.
No hidden fees, nice discounts for regular checkups.
Save a trip to the doctor, go directly to the lab
Instant orders, results often overnight*
Results explained in simple language
Reviewed by US licensed doctors
Fast & confidential, we never sell or share your data
No insurance needed, transparent pricing
Demo results
Vitamin B12 245 pg/mL
Demo results
Low Optimal 300 - 900 High
245 pg/mL

What this means

Your vitamin B12 levels are slightly below the optimal range. While not severely deficient, this may contribute to fatigue, reduced energy, difficulty concentrating, or weakness you might be experiencing. Addressing this early can help prevent more serious symptoms from developing.

* Regular blood test results (e.g., CBC) typically start arriving the next business day after sample collection. More complex tests, such as hormone panels, may take up to 10–15 business days due to their complexity.
Here’s how easy it is to get blood work done on your terms
Choose a checkup
Order your test Save a trip to the doctor. Your results will come with clear, friendly explanations. Takes 2 minutes
Book a lab
Book an appointment Visit any of our 4,000 nearby lab locations to have your samples collected. Book or walk-in
Choose a checkup
Get results Receive a clear, easy-to-digest health report by email & SMS within a few business days. Get answers, fast

Blood Test for Fatigue and Low Energy (Vitamin B12)

Google
3,141 reviews
  • Pinpoint the cause of your fatigue
  • Reveal hidden vitamin B12 deficiencies
  • Enhance your energy levels effectively

1,000,000+ blood tests later, here's what our customers say

Google reviews 3141 reviews Next
Still got questions? Text our super-cool support team at 754-799-7833 to get help finding your ideal checkup.