Who should use Healthmatters?

Individuals who want to track and understand their health over time, health professionals, such as doctors, nutritionists, and wellness coaches, need to manage and interpret lab data for their clients.

What can I do with a Healthmatters account?

With a Healthmatters account, you can: Upload lab reports from any lab, View your data in interactive graphs, tables, and timelines, Track trends and monitor changes over time, Customize your reference ranges, Export and share your full lab history, Access your results anytime, from any device. Professionals can also analyze client data more efficiently and save time managing lab reports.

What test results do you interpret?

Healthmatters.io personal account provides in-depth research on 10000+ 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.

Do you only accept reports from specific labs listed here?

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.

How do I get reports into my 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.

What is the Data Entry Service, and why does it cost $15 per report?

Our Data Entry Service is for when you don't want to manually type in your lab results yourself. You simply upload your report (PDF, image, or screenshot), and our trained team enters the information into your Healthmatters account for you — accurately and neatly organized, ready to view in graphs, tables, and timelines. The $15 per report covers the time and care it takes for a real person to review your file, make sure each result is entered correctly, and double-check for accuracy. This ensures your health data is precise and easy to work with — without you having to spend the time doing it yourself. Prefer to do it yourself? You can always use our free self-entry tool to add results manually — it just takes a bit more time and attention.

Does a personal account come with a data entry service?

For users on the Advanced Plan, the first 5 reports are included free of charge, and each additional report incurs a $15 fee. Unlimited Plan holders enjoy the entry of 10 reports at no charge. Subsequent reports are subject to a $15 fee per report. Additionally, users on the Advanced Plan can upgrade to the Unlimited Plan from their account settings.

How much does a professional account cost?

All professional accounts allow you to import and onboard an unlimited number of clients and their lab results. The distinction between professional plans lies solely in the data entry service. The Pro Monthly Plus plan is priced at $75 per month and includes a data entry service for five reports each month. Additional reports can be self-entered at no extra cost or, if preferred, you can use our data entry service for an additional fee of $15 per report. The Pro Monthly plan is priced at $45 per month and does not include a data entry service. Self-entry is free for an unlimited number of reports, and you can opt for the data entry service at a fee of $15 per report. You also have the option to upgrade to higher monthly or to annual plans, which come with substantial discounts. All upgrades can be done directly from your account.

How do I terminate my account?

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.

Can I download my information from my account?

Yes, you can download your information anytime. We offer two easy ways to export your lab data: 1. Download a CSV file: Go to Account Settings and scroll to the bottom of the page. There, you'll find a link to download all your labs as a CSV file. 2. Download an Excel file: To export your data in Excel format, go to either the Graph or Table view and click “Export Excel File.”

Can I print my report?

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.

Can I secure my account with Two-Factor Authentication (2FA)?

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.

Can I use a custom range for biomarkers?

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.

What’s the difference between personal and professional accounts?

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.

Where can I learn more about professional accounts?

To learn more about Healthmatters Pro, please refer to the professional page.

Can I share my results in the HealthMatters dashboard with my doctor?

Yes, you can! Simply go to the 'Invite Doctor' section, enter your doctor’s email address, and send the invitation. Your doctor will receive an email with secure access to view your results. You can revoke this access at any time. All shared information is securely encrypted and protected for your privacy.

Can I export my information to an Excel file?

Yes, you can! Go to the Graph view or Spreadsheet view. In the top-right corner, click 'Export to Excel,' and the file will be downloaded to your device.

RDW-SD (Red Cell Distribution Width) in fL

Q: What is Healthmatters, and who is it for?

Healthmatters is a personal health dashboard that helps you organize and understand your lab results. It collects and displays your medical test data from any lab in one secure, easy-to-use platform.

Whole Blood

Optimal Result: 39 - 46 fl.

CBC Blood Test: How to Read Results, Normal Ranges, and What High or Low Means

Reviewed by HealthMatters Editorial Team · Last updated February 2026

What does RDW-SD mean on a blood test?

Most people with a slightly high or slightly low RDW-SD result do not have a serious condition. Mild changes are common and often temporary, especially with minor illness, recovery from infection, or nutrient shifts. Doctors interpret RDW-SD together with hemoglobin, MCV, iron levels, and the rest of your complete blood count (CBC).

RDW-SD (Red Cell Distribution Width – Standard Deviation) measures how much your red blood cells vary in size. It helps clinicians understand whether red blood cells are being produced normally and can provide early clues about anemia, nutrient deficiencies, inflammation, or recovery from illness.

Unlike RDW-CV (which is a percentage), RDW-SD is measured in femtoliters (fL) and reflects the actual width of the red blood cell size distribution.

A higher RDW-SD means there is more variation in red blood cell size.
A lower RDW-SD means your red blood cells are more uniform in size.

On its own, RDW-SD does not diagnose a condition. It is interpreted alongside hemoglobin, MCV, iron levels, and other CBC markers.

Small variations in RDW-SD are very common and are usually not dangerous when the rest of your CBC is normal.

RDW-SD normal range

Typical reference range for adults:

RDW-SD: ~39–46 fL

Ranges vary slightly by laboratory and age.

Values just outside the range are common and not always clinically significant. RDW-SD is most meaningful when interpreted with other red blood cell markers.

What does low RDW-SD mean?

A low RDW-SD means your red blood cells are very similar in size.

In most cases, low RDW-SD is not dangerous and does not indicate disease.

It may be seen when:

red blood cells are uniformly small
red blood cells are uniformly large
overall cell production is stable
other CBC values are normal

If hemoglobin, MCV, and iron levels are normal, a low RDW-SD is usually not a concern.

What does high RDW-SD mean?

A high RDW-SD indicates greater variation in red blood cell size. This is called anisocytosis.

Common causes include:

iron deficiency
vitamin B12 deficiency
folate deficiency
recent blood loss
chronic disease
bone marrow stress
recovery after anemia treatment

RDW-SD often rises early in anemia and may increase before hemoglobin drops significantly.

What level of RDW-SD is dangerous?

There is no single RDW-SD value that is dangerous on its own.

However, higher values may be more clinically significant when they occur with:

low hemoglobin
abnormal MCV
fatigue or shortness of breath
iron deficiency
chronic illness

RDW-SD above ~50 fL is more likely to reflect significant variation in red blood cell size and should be interpreted with other lab results.

What do specific RDW-SD numbers mean?

These ranges are general guidelines and vary by lab.

RDW-SD 39–46 fL
Typically normal.

RDW-SD 47–49 fL
Mildly elevated. May indicate early iron deficiency or nutrient imbalance.

RDW-SD ≥50 fL
More significant variation in cell size. Should be interpreted with hemoglobin and MCV.

Low RDW-SD (<39 fL)
Usually not concerning and often clinically insignificant if other labs are normal.

RDW-SD low but other labs are normal

A low RDW-SD with normal hemoglobin and MCV is usually benign.

Providers typically do not treat low RDW-SD alone. It is considered a minor variation rather than a disease marker.

RDW-SD vs RDW-CV

Both markers measure variation in red blood cell size:

RDW-SD

Measured in femtoliters
Absolute size variation
Not affected by MCV

RDW-CV

Percentage
Influenced by MCV
Used with anemia classification

Many clinicians consider RDW-SD a more direct measurement of size variability.

Symptoms related to abnormal RDW-SD

RDW-SD itself does not cause symptoms. Symptoms come from the underlying condition, such as anemia.

Possible symptoms when RDW-SD is elevated:

fatigue
weakness
shortness of breath
dizziness
pale skin
cold hands and feet

How clinicians interpret RDW-SD

RDW-SD is evaluated alongside:

hemoglobin
MCV
MCH
ferritin
B12
folate
reticulocytes

It helps identify patterns of anemia and red blood cell production.

Key takeaway

RDW-SD measures how much your red blood cells vary in size.
A high RDW-SD may suggest anemia or nutrient deficiency.
A low RDW-SD is usually not clinically significant.

The result is most meaningful when interpreted with the rest of your CBC and your overall health.

What does it mean if your RDW-SD (Red Cell Distribution Width) in fL result is too high?

A high RDW-SD means there is more variation in the size of your red blood cells.
This is called anisocytosis.

High RDW-SD is commonly associated with anemia or nutrient deficiencies, but it does not diagnose a condition on its own.

Common causes of high RDW-SD

High RDW-SD may occur with:

Iron deficiency
One of the most common causes.

Vitamin B12 or folate deficiency

Recent blood loss

Chronic disease or inflammation

Recovery from anemia treatment

Liver disease

Bone marrow stress

RDW-SD often rises early in anemia before hemoglobin drops significantly.

RDW-SD and MCV patterns

Clinicians interpret RDW-SD together with MCV:

High RDW + low MCV
Often suggests iron deficiency.

High RDW + high MCV
May suggest B12 or folate deficiency or liver disease.

High RDW + normal MCV
Can occur in early anemia or mixed deficiencies.

When high RDW-SD is more concerning

High RDW-SD may require evaluation if it appears with:

low hemoglobin
fatigue
shortness of breath
dizziness
chronic illness

Higher values (often above ~50 fL) may reflect more significant variation in red blood cell size and should be interpreted with other labs.

Key takeaway

High RDW-SD indicates variation in red blood cell size and is often associated with anemia or nutrient deficiency. It is most meaningful when interpreted alongside hemoglobin, MCV, and iron studies.

All Your Lab Results.
One Simple Dashboard.

Import, Track, and Share Your Lab Results Easily

Import, Track, and Share Your Lab Results

Import lab results from multiple providers, track changes over time, customize your reference ranges, and get clear explanations for each result. Everything is stored securely, exportable in one organized file, and shareable with your doctor—or anyone you choose.

Cancel or upgrade anytime

What does it mean if your RDW-SD (Red Cell Distribution Width) in fL result is too low?

A low RDW-SD means your red blood cells are very similar in size.
In most cases, this is not dangerous and does not indicate a disease.

Low RDW-SD is usually considered a normal variation, especially if hemoglobin, MCV, and other CBC values are normal.

Why RDW-SD can be low

RDW-SD reflects how much red blood cell sizes vary. A lower value simply means the cells are more uniform.

This can occur when:

Normal healthy state
Many healthy people have slightly low RDW-SD with no underlying condition.

Uniform red blood cell size
If red blood cells are consistently small or consistently large, RDW-SD can appear low even when there is no serious problem.

Stable red blood cell production
When bone marrow production is steady and consistent, red blood cells tend to be similar in size.

When low RDW-SD might be evaluated further

Low RDW-SD alone is rarely concerning.
Further evaluation may be considered if it appears with:

low hemoglobin
abnormal MCV
symptoms of anemia
chronic illness

In these cases, providers look at:

iron levels
B12 and folate
inflammation markers

Symptoms related to underlying causes

Low RDW-SD itself does not cause symptoms.
If an underlying condition exists, symptoms may include:

fatigue
weakness
dizziness
shortness of breath

Most people with low RDW-SD and normal labs have no symptoms.

Key takeaway

Low RDW-SD usually reflects uniform red blood cell size and is typically not a cause for concern. It is interpreted together with the rest of your CBC and overall health.

Laboratories

Bring All Your Lab Results Together — In One Place

We accept reports from any lab, so you can easily collect and organize all your health information in one secure spot.

Pricing Table

Gather Your Lab History — and Finally Make Sense of It

Finally, Your Lab Results Organized and Clear

Choose the plan that fits you — and turn scattered lab reports into clear insights you can finally use.

Pick a plan that fits you — and turn scattered lab reports into clarity.

Personal plans

Professional plan

$79/ year

Advanced Plan

Access your lab reports, explanations, and tracking tools.

Import lab results from any provider
Track all results with visual tools
Customize your reference ranges
Export your full lab history anytime
Share results securely with anyone
Receive 5 reports entered for you
Cancel or upgrade anytime

$250/ once

Unlimited Account

Pay once, access everything—no monthly fees, no limits.

Import lab results from any provider
Track all results with visual tools
Customize your reference ranges
Export your full lab history anytime
Share results securely with anyone
Receive 10 reports entered for you
No subscriptions. No extra fees.

Professional plan

$45/ month

Pro Monthly

Designed for professionals managing their clients' lab reports

Import lab results from any provider
Track lab results for multiple clients
Customize reference ranges per client
Export lab histories and reports
Share results and reports with clients
Invite clients to their accounts
Begin with first report entered by us
Cancel or upgrade anytime

About membership

What's included in a Healthmatters membership

Import Lab Results from Any Source

Easily upload lab results from any provider, whether it's a hospital, independent lab, or home testing service. We support PDFs, scanned documents, and JPEGs from patient portals. No need to log in to multiple platforms — everything is centralized in one secure space.

Easily upload lab results from any provider — we support PDFs, scans, and images. Keep all your reports organized in one secure place.

See Your Health Timeline

Every lab result is automatically organized on a chronological timeline, giving you a complete picture of your health journey. Whether you're tracking a condition, managing treatments, or staying proactive, the timeline helps you and your doctor understand how things progress over time.

Every lab result is automatically organized on a chronological timeline, giving you a complete picture of your health journey.

Understand What Your Results Mean

Whether it's a blood test, GI panel, urinalysis, or something else, lab reports measure numerous biomarkers that reveal what's happening inside your body. Our extensive database covers over 10,000 biomarkers, providing clear, simple explanations of what each result means and how you can take action—no matter your membership level. Say goodbye to confusion and get the insights you need to better understand your health.

Our database covers over 10,000 biomarkers with clear, simple explanations—so you can finally understand your results and what to do next.

Enter Your Lab Reports Yourself — Always Free Enter Your Lab Reports — Always Free

If you'd like to handle inputting your health data into your account, you can do so with our easy-to-use data entry forms. Our user-friendly form is designed to guide you through the quick and easy submission process, making it simple to keep track of your health metrics. This is available to both Advanced plan and Unlimited plan members.

Our user-friendly form guides you through a quick, simple submission process, making it easy to enter your health metrics.

Add your results anytime with our easy entry form. It's quick, guided, and helps you stay organized — free for all members.

Visualize Your Results

View your lab data through easy-to-read graphs and tables. Quickly spot patterns, track changes, and compare results across different dates — all without digging through multiple reports. You can also select and compare graphs of specific biomarkers side-by-side to better understand how they relate and change over time.

See your lab reports in clear graphs and tables. Spot patterns, track changes, and compare results over time — all in one place.

Export Your Complete Lab History in a Single File Export Your Complete Lab History

After collecting lab results from different providers, you can download your entire history combined into a single file. Choose from PDF, Excel, or CSV formats to easily review, share, or get a second opinion—no more juggling multiple reports.

After collecting lab results from different providers, you can download your entire history combined into a single file.

Comprehensive Data Entry Service for Your Reports Data Entry Service for Your Reports

Our inclusive service handles the data entry for your lab reports. Just submit your information and we'll take care of the rest. Advanced plan members receive five reports entered for free, then $15 per report after that. Unlimited plan members receive ten report entries for free, then $15 per report after that.

Our inclusive service handles the data entry for your lab reports. Just submit your information and we'll take care of the rest.

Securely Share With Anyone You Trust

Whether you're working with a doctor, nutritionist, caregiver, or wellness coach, you can securely share your complete lab history by sending an invite link to anyone you trust. You have full control over who sees your information and for how long, ensuring your privacy and peace of mind at every step.

Share your full lab history with your doctor, nutritionist, or coach using a secure invite link.

Discover

Let Your Lab Results Tell the Full Story

Once your results are in one place, see the bigger picture — track trends over time, compare data side by side, export your full history, and share securely with anyone you trust.

Bring all your results together to compare, track progress, export your history, and share securely.

I have been using Healthmatters.io since 2021. I travel all over the world and use different doctors and health facilities. This site has allowed me to consolidate all my various test results over 14 years in one place. And every doctor that I show this to has been impressed. Because with any health professional I talk to, I can pull up historical results in seconds. It is invaluable. Even going back to the same doctor, they usually do not have the historical results from their facility in a graph format. That has been very helpful.

Anthony

Unlimited Plan Member since 2021

What fantastic service and great, easy-to-follow layouts! I love your website; it makes it so helpful to see patterns in my health data. It's truly a pleasure to use. I only wish the NHS was as organized and quick as Healthmatters.io. You've set a new standard for health tracking!

Karin

Advanced Plan Member since 2020

As a PRO member and medical practitioner, Healthmatters.io has been an invaluable tool for tracking my clients' data. The layout is intuitive, making it easy to monitor trends and spot patterns over time. The ability to customize reports and charts helps me present information clearly to my clients, improving communication and outcomes. It's streamlined my workflow, saving me time and providing insights at a glance. Highly recommended for any practitioner looking for a comprehensive and user-friendly solution to track patient labs!

Paul

Healthmatters Pro Member since 2024

Frequently asked questions

Healthmatters is a personal health dashboard that helps you organize and understand your lab results. It collects and displays your medical test data from any lab in one secure, easy-to-use platform.

Individuals who want to track and understand their health over time.
Health professionals, such as doctors, nutritionists, and wellness coaches, need to manage and interpret lab data for their clients.

With a Healthmatters account, you can:

Upload lab reports from any lab
View your data in interactive graphs, tables, and timelines
Track trends and monitor changes over time
Customize your reference ranges
Export and share your full lab history
Access your results anytime, from any device

Professionals can also analyze client data more efficiently and save time managing lab reports.

Healthmatters.io personal account provides in-depth research on 10000+ 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.

The Advanced Plan ($79/year) is perfect for individuals who want ongoing access to their health data. It includes unlimited self-entry of lab reports, visual tracking, custom ranges, result explanations, full account exports, and secure sharing — all with a simple yearly subscription. The plan also includes free data entry of up to 5 reports by our data entry team. You can cancel anytime and restart your plan whenever you're ready — your data will still be there waiting for you. You can also upgrade to the Unlimited Plan at any time, with the cost prorated based on what you've already paid.

The Unlimited Plan ($250 one-time) is also designed for individuals but offers lifetime access with no ongoing subscription. You'll get all the same features as the Advanced Plan, plus free data entry of up to 10 reports by our data entry team, making it a great choice if you prefer a one-time payment and long-term use without yearly fees.

In short:

Advanced Plan → Best for those who want to try the service for less (cancel/restart anytime, upgrade to Unlimited anytime).
Unlimited Plan → Best for long-term users who prefer to pay once and keep access forever.

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.

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.

RDW-SD (Red Cell Distribution Width) in fL

What does RDW-SD mean on a blood test?

RDW-SD normal range

What does low RDW-SD mean?

What does high RDW-SD mean?

What level of RDW-SD is dangerous?

What do specific RDW-SD numbers mean?

RDW-SD low but other labs are normal

RDW-SD vs RDW-CV

Symptoms related to abnormal RDW-SD

How clinicians interpret RDW-SD

Key takeaway

What does it mean if your RDW-SD (Red Cell Distribution Width) in fL result is too high?

Common causes of high RDW-SD

RDW-SD and MCV patterns

When high RDW-SD is more concerning

Key takeaway

All Your Lab Results. One Simple Dashboard.

Import, Track, and Share Your Lab Results Easily

Import, Track, and Share Your Lab Results

What does it mean if your RDW-SD (Red Cell Distribution Width) in fL result is too low?

Why RDW-SD can be low

When low RDW-SD might be evaluated further

Symptoms related to underlying causes

Key takeaway

Bring All Your Lab Results Together — In One Place

Gather Your Lab History — and Finally Make Sense of It

Finally, Your Lab Results Organized and Clear

Advanced Plan

Unlimited Account

Pro Monthly

What's included in a Healthmatters membership

Import Lab Results from Any Source

See Your Health Timeline

Understand What Your Results Mean

Enter Your Lab Reports Yourself — Always Free Enter Your Lab Reports — Always Free

Visualize Your Results

Export Your Complete Lab History in a Single File Export Your Complete Lab History

Comprehensive Data Entry Service for Your Reports Data Entry Service for Your Reports

Securely Share With Anyone You Trust

Let Your Lab Results Tell the Full Story

Once your results are in one place, see the bigger picture — track trends over time, compare data side by side, export your full history, and share securely with anyone you trust.

Bring all your results together to compare, track progress, export your history, and share securely.

What Healthmatters Members Are Saying

Use promo code to save 10% off any plan.

Frequently asked questions

We implement proven measures to keep your data safe.

All Your Lab Results.
One Simple Dashboard.