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C-Peptide test for people with blood sugar issues and diabetes management concerns

Blood Test for Diabetes and Blood Sugar Issues

C-Peptide, Serum

Google
3,138 reviews
  • Pinpoint insulin production issues accurately
  • Reveal hidden causes of blood sugar spikes
  • Clarify your diabetes management strategy 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 unexplained low blood sugar episodes, have been diagnosed with diabetes and want to understand how much insulin your body is making, or if your doctor suspects an insulin-producing tumor. It helps distinguish between type 1 and type 2 diabetes, monitors pancreatic function after transplants, and clarifies whether blood sugar problems are due to your body's own insulin production or external insulin. Many people use this test to get a clearer picture of their diabetes management strategy.

How should I prepare for this test?

Fasting: 12 hours

You'll need to fast for 12 hours before your blood draw. This means no food or beverages except water during this time. Fasting ensures accurate C-Peptide measurement since eating affects insulin and C-Peptide release. Schedule your test for early morning so you can fast overnight, and bring any medications to take after your test is complete.

What's included in this test?

C-Peptide

This test measures C-Peptide, a protein released by your pancreas when it produces insulin. C-Peptide levels reveal how much natural insulin your body is making, which is crucial for understanding the root cause of blood sugar imbalances and distinguishing between different types of diabetes. Unlike insulin measurements, C-Peptide provides a more stable and accurate picture of your pancreatic function, making it invaluable for diagnosis and ongoing diabetes management.

What happens after I get my results?
You'll receive detailed doctor notes in simple language explaining what your C-Peptide level means for your insulin production and blood sugar control. These notes include personalized recommendations like dietary adjustments, medication timing considerations, or whether you should discuss insulin therapy options with your endocrinologist. You'll also get the standard lab report and can track your C-Peptide levels over time using our trends feature to see how your pancreatic function changes with treatment or lifestyle modifications.
When will I get my results?
Most C-Peptide test results are available within 1-3 business days after your sample reaches the laboratory. You'll receive an email notification when your results are ready to view in your secure online account, along with easy-to-understand doctor notes explaining what your levels mean.
Who should consider getting this test?
This test is valuable for anyone with diabetes who wants to understand their body's natural insulin production, people experiencing frequent low blood sugar episodes without clear cause, or those whose doctors are trying to determine whether they have type 1 or type 2 diabetes. It's also important for individuals who've had pancreatic or islet cell transplants and need to monitor pancreatic function, or anyone suspected of having an insulin-producing tumor.
What symptoms indicate I may need this test?
You might need this test if you experience frequent episodes of shakiness, sweating, confusion, or weakness from low blood sugar, especially if you're not taking insulin. It's also helpful if you have diabetes symptoms like increased thirst and urination but it's unclear what type of diabetes you have, or if you're on diabetes medication but your blood sugar remains difficult to control. Some people need this test when investigating unexplained weight changes or suspecting problems with insulin production.
How can I naturally support healthy insulin production?
Supporting pancreatic health starts with eating balanced meals that combine protein, healthy fats, and fiber to avoid blood sugar spikes. Regular exercise improves insulin sensitivity and helps your pancreas work more efficiently. Managing stress through meditation or deep breathing, getting 7-8 hours of quality sleep, and maintaining a healthy weight all support optimal insulin and C-Peptide levels. Avoiding processed foods and excessive sugar reduces the burden on your pancreas.
What is C-Peptide and why does it matter?
C-Peptide is a small protein that's released into your bloodstream when your pancreas makes insulin. Measuring it tells doctors how much natural insulin your body is producing, which is crucial for diagnosing diabetes types and monitoring pancreatic function. Unlike insulin itself, C-Peptide isn't affected by insulin injections and lasts longer in the blood, making it a more reliable marker. Understanding your C-Peptide level helps personalize your diabetes treatment and identify the root cause of blood sugar problems.
What does low C-Peptide mean?
Low C-Peptide levels indicate that your pancreas is producing little or no insulin on its own. This is typical in type 1 diabetes where the immune system has destroyed insulin-producing cells, or in advanced type 2 diabetes where the pancreas has become exhausted. Low levels mean you'll likely need insulin therapy since your body can't make enough naturally. It can also occur after pancreatic surgery or damage to the pancreas.
What does high C-Peptide mean?
High C-Peptide levels suggest your pancreas is working overtime to produce insulin, which often happens in early type 2 diabetes when your body becomes resistant to insulin. It can also indicate an insulin-producing tumor (insulinoma) if accompanied by low blood sugar episodes. Elevated C-Peptide with high blood sugar typically means insulin resistance, while high C-Peptide with low blood sugar may point to a tumor. Your doctor will interpret your results alongside your symptoms and blood glucose levels.
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
C-Peptide 0.8 ng/mL
Demo results
Low Optimal 1.1 - 4.4 High
0.8 ng/mL

What this means

Your C-Peptide level is below the optimal range, indicating that your pancreas is producing less insulin than ideal. This may suggest diminished pancreatic beta cell function, which is common in type 1 diabetes or advanced type 2 diabetes, and may explain difficulties with blood sugar control.

* 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 Diabetes and Blood Sugar Issues

Google
3,138 reviews
  • Pinpoint insulin production issues accurately
  • Reveal hidden causes of blood sugar spikes
  • Clarify your diabetes management strategy effectively

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

Google reviews 3138 reviews Next
Still got questions? Text our super-cool support team at 754-799-7833 to get help finding your ideal checkup.