Bicarbonate (HCO3), Serum

Optimal Result: 22 - 29 mmol/L.

Bicarbonate is an electrolyte, a negatively charged ion that is used by the body to help maintain the body’s acid-base (pH) balance. It also works with the other electrolytes (sodium, potassium, and chloride) to maintain electrical neutrality at the cellular level. This test measures the total amount of carbon dioxide (CO2) in the blood, which occurs mostly in the form of bicarbonate (HCO3–). The CO2 is mainly a by-product of various metabolic processes.

Measuring bicarbonate as part of an electrolyte or metabolic panel may help diagnose an electrolyte imbalance or acidosis or alkalosis. Acidosis and alkalosis describe the abnormal conditions that result from an imbalance in the pH of the blood caused by an excess of acid or alkali (base). This imbalance is typically caused by some underlying condition or disease.

The lungs and kidneys are the major organs involved in regulating blood pH through the removal of excess bicarbonate.

The lungs flush acid out of the body by exhaling CO2. Raising and lowering the respiratory rate alters the amount of CO2 that is breathed out, and this can affect blood pH within minutes.

The kidneys eliminate acids in the urine and they regulate the concentration of bicarbonate (HCO3–, a base) in blood. Acid-base changes due to increases or decreases in HCO3– concentration occur more slowly than changes in CO2, taking hours or days.

Any disease or condition that affects the lungs, kidneys, metabolism, or breathing has the potential to cause acidosis or alkalosis.

The bicarbonate test gives a healthcare practitioner a rough estimate of your acid-base balance. This is usually sufficient, but measurements of gases dissolved in the blood (blood gases) may be done if more information is needed. Bicarbonate is typically measured along with sodium, potassium, and possibly chloride in an electrolyte panel as it is the balance of these molecules that gives the healthcare practitioner the most information.

Bicarbonate Reference Ranges:

The reference ranges provided here represent a theoretical guideline that should not be used to interpret your test results. Some variation is likely between these numbers and the reference range reported by the lab that ran your test. Please consult your healthcare provider.

AGE CONVENTIONAL UNITS2 SI UNITS3
0-18 years Not available due to wide variability. See child’s lab report for reference range.
Adult 23-29 mEq/L 23-29 mmol/L
>60 years 23-31 mEq/L 23-31 mmol/L
>90 years 20-29 mEq/L 20-29 mmol/L

What does it mean if your Bicarbonate (HCO3), Serum result is too high?

A bicarbonate level that is higher or lower than normal may mean that the body is having trouble maintaining its acid-base balance, either by failing to remove carbon dioxide through the lungs or the kidneys or perhaps because of an electrolyte imbalance, particularly a deficiency of potassium. Both of these imbalances may be due to a wide range of conditions.

Examples of conditions that can cause a high bicarbonate level include:

- Severe, prolonged vomiting and/or diarrhea

- Lung diseases, including COPD

- Cushing syndrome

- Conn syndrome

- Metabolic alkalosis

What does it mean if your Bicarbonate (HCO3), Serum result is too low?

A bicarbonate level that is higher or lower than normal may mean that the body is having trouble maintaining its acid-base balance, either by failing to remove carbon dioxide through the lungs or the kidneys or perhaps because of an electrolyte imbalance, particularly a deficiency of potassium. Both of these imbalances may be due to a wide range of conditions.

Examples of conditions that can cause a low bicarbonate level include:

- Addison disease

- Chronic diarrhea

- Diabetic ketoacidosis

- Metabolic acidosis

- Respiratory alkalosis, which can be caused by hyperventilation

- Shock

- Kidney disease

- Ethylene glycol or methanol poisoning

- Salicylate (aspirin) overdose

Frequently asked questions

Healthmatters is a highly-personalized health dashboard.

Instead of searching for your lab results in different places or tracking them down from different providers, Healthmatters houses, organizes, and interprets them all in one central location.

With a Healthmatters account, you can dive into the details of each biomarker and gain insights into the meaning behind your medical test data, anytime, anywhere.

For our professional users, Healthmatters provides intuitive tools that not only streamline analysis but also save valuable time when delving into your client's lab report history.

Healthmatters.io personal account provides in-depth research on 4000+ biomarkers, including information and suggestions for test panels such as, but not limited to:

  • The GI Effects® Comprehensive Stool Profile,
  • GI-MAP,
  • The NutrEval FMV®,
  • The ION Profile,
  • Amino Acids Profile,
  • Dried Urine Test for Comprehensive Hormones (DUTCH),
  • Organic Acids Test,
  • Organix Comprehensive Profile,
  • Toxic Metals,
  • Complete Blood Count (CBC),
  • Metabolic panel,
  • Thyroid panel,
  • Lipid Panel,
  • Urinalysis,
  • And many, many more.

You can combine all test reports inside your Healthmatters account and keep them in one place. It gives you an excellent overview of all your health data. Once you retest, you can add new results and compare them.

If you are still determining whether Healthmatters support your lab results, the rule is that if you can test it, you can upload it to Healthmatters.

While we work with many popular labs, we welcome reports from lots of other places too.

It's as simple as this: if you can get a test done, you can upload it to Healthmatters and we can interpret results from any lab out there. If laboratories can analyze it, we can interpret it.

If you’re on the hunt for a specific biomarker, contact us and we'll add it to our database. Anything from blood, urine, saliva, or stool can be uploaded, understood, and tracked with your Healthmatters account.

There are two ways to add your test reports to your Healthmatters account. One option is to input the data using the data entry forms. The other method is to utilize our "Data entry service."

Our data entry forms offer an easy, fast, and free way for you to input the reports yourself. Self-entry allows you to add an unlimited number of reports at no cost. We make the self-entry process user-friendly, providing dozens of templates that pre-populate the most popular laboratory panels and offering instant feedback on entered values.

For those who prefer assistance, we offer a "Data entry service" to help you input your data. Simply attach an image or file of your lab test results, and a qualified team member from our data entry team will add the results for you.

We support various file types, including PDFs, JPGs, or Excel. This service is particularly useful if you have many reports to upload or if you're too busy to handle the data entry yourself.

Our special data entry service makes it easy to add your results to your private dashboard. Just attach an image or a file of your lab test results, and our skilled data entry team will do the work for you. It's all done by humans, ensuring that your data is entered accurately and with personal care for each client.

Depending on your account, the data entry service can be included for free or come at an additional cost of $15 per report.

For users on the Complete monthly plan, the first report is entered free of charge, and each additional report incurs a fee of $15.

Unlimited account holders enjoy the entry of ten reports without charge. Subsequent reports are subject to a $15 fee per report.

Additionally, users on the Complete plan can upgrade to a yearly subscription from the account settings. The annual subscription includes a data entry service for five reports.

The Unlimited plan is a one-time purchase for $250, and it covers your account for a lifetime with no additional payments.

For the Complete plan, the cost is $15 per month. You have the flexibility to cancel it anytime through your account settings, ensuring no further payments. To avoid charges, remember to cancel at least a day before the renewal date. Once canceled, the subscription remains active until the end of the current billing cycle.

Additionally, you can upgrade to the yearly Advanced plan from within your account. The annual cost is $79, and it comes with a data entry service for five reports.

You can always upgrade to a lifetime version with a prorated price from a monthly or yearly subscription.

Simply log in and navigate to your account settings to cancel your subscription. Scroll down to locate the 'Cancel' button at the bottom of the page. Ensure you cancel at least one day before the renewal date to prevent any charges. Once cancellation is requested, the subscription remains active until the conclusion of the current billing cycle.

Our goal has been to make your Healthmatters account as intuitive as possible.

We’ve crafted multiple ways for you to navigate your data, whether you're glancing at a single report or delving into your historical test reports.

1. Graph View:

Dive into a visual journey with our biomarker graphs, showcasing over 40 data points. Combining years of results unveils trends, empowering you to make informed decisions. Our visualization tools make it a breeze to compare and understand changes over time, even if your results are from different labs. A search function and filters simplify the exploration of extensive data, allowing you to focus on what needs attention.

2. All Tests View

Explore neatly organized reports on a timeline, highlighting crucial details like dates, critical results, and lab/panel names. Each report opens up to reveal in-depth descriptions and additional recommendations for each biomarker. The history of previous results is just a click away, and you can download a comprehensive report for deeper insights. Color-coded and user-friendly, it's designed for easy reading, understanding, and navigation.

3. Table View:

For a holistic view of all biomarkers side by side, our table view is your go-to. Results are neatly displayed in a categorized and dated table, ideal for those with an extensive test history. Utilize sorting, filters, and color-coding to enhance your analysis and gain extra insights.

Yes, you can download information from your account. We can compile your labs into a CSV file. To download all your labs, you can go to Account Settings, and at the bottom of the page, you will find a link to download your information.

Yes, you can print your report. To do so, navigate to "All tests" and open the report you wish to print. You'll find a print button in the right corner of the report. Click on it, and your browser's print window will open. If you prefer to print in a bigger typeface, adjust the scale using the print window settings.

Yes, you can! We highly recommend activating Two-Factor Authentication (2FA) for your account. To do so, please navigate to the "Profile and Security" section of your account, where you will find instructions for activating 2FA.

Yes, you can. When entering values for the biomarker, you will see an "Edit Range" button. Click this button, and you'll have the option to enter a custom range.

A personal account is all about keeping your own lab test results in check. It's just for you and your personal use.

The professional account is designed for health professionals who wish to track and organize their clients' laboratory results.

Use promo code to save 10% off any plan.


We implement proven measures to keep your data safe.

At HealthMatters, we're committed to maintaining the security and confidentiality of your personal information. We've put industry-leading security standards in place to help protect against the loss, misuse, or alteration of the information under our control. We use procedural, physical, and electronic security methods designed to prevent unauthorized people from getting access to this information. Our internal code of conduct adds additional privacy protection. All data is backed up multiple times a day and encrypted using SSL certificates. See our Privacy Policy for more details.