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Detection of Prediabetes

How prediabetes is detected: the A1C, fasting glucose, and oral glucose tolerance tests, plus CGM and risk screening to catch high blood sugar early.

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1-Hour Glucose Test Normal Range

A clear breakdown of the 1-hour glucose test, what counts as a normal result in pregnancy and beyond, and how to prepare for accurate numbers.

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1,5-Anhydroglucitol (1,5-AG)

A complete guide to 1,5-anhydroglucitol (1,5-AG) — how it tracks short-term glucose excursions, the GlycoMark assay.

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2-Hour Glucose Test: What It Measures and How to Prepare

How the 2-hour oral glucose tolerance test works, what to expect, how to prepare, what each result means, and when your clinician orders it instead of A1C.

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2-Hour Glucose Tolerance Test

A clear walk-through of the 2-hour 75g oral glucose tolerance test, including ADA cutoffs, day-of preparation.

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3-Hour Glucose Test Results

How to interpret 3-hour oral glucose tolerance test results in pregnancy — the Carpenter-Coustan cutoffs, what two abnormal values mean.

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A1C 5.5 Fasting: How It Works, Accuracy, and When to Use It

A1C 5.5% is within the normal range. The A1C test itself is not a fasting test, but pairing it with fasting glucose gives a fuller screening picture.

A1C 5.7 Fasting: How It Works, Accuracy, and When to Use It

A1C is not a fasting test, but pairing A1C 5.7% with a fasting glucose reading gives the clearest picture of early prediabetes.

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A1C Blood Test: What to Expect and How to Read Results

A practical walk-through of the A1C blood test - what to expect, why no fasting is needed, what it costs, and how to interpret your results.

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A1C Fasting or Not: How It Works, Accuracy, and When to Use

Wondering about A1C fasting or not? You don't need to fast before an A1C test. Here's why, how the test works, and when fasting actually does matter.

A1C Meter: How It Works, Accuracy, and How to Use One

An A1C meter is a portable device that estimates your 3-month average blood sugar from a finger-prick sample. Here is how accurate it is.

A1C Monitor Without Finger Pricks

A1C monitor without finger pricks? The closest option is a continuous glucose monitor that calculates a Glucose Management Indicator.

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A1C Monitor: How It Works, Accuracy, and How to Use One

At-home A1C monitors give lab-comparable results in five minutes. See how they work, which devices are accurate, and how to get the most reliable reading.

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A1C Test Kit: At-Home Options, Accuracy, and How to Use One

At-home A1C test kits offer a convenient snapshot of your 3-month average glucose. Here is how they compare to lab tests and when to use one.

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Abbott Libre: How It Works, Accuracy, and When to Use It

An overview of Abbott's FreeStyle Libre CGM line for people with diabetes and the Lingo biosensor for wellness use.

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Abbott Lingo: How Abbott’s OTC Glucose Sensor Differs From

Abbott split its CGM portfolio in two — FreeStyle Libre for diabetes management and Lingo for over-the-counter wellness.

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Adiponectin Levels and Prediabetes

Adiponectin and prediabetes are linked: this fat-tissue hormone improves insulin sensitivity, and low levels are an early marker of insulin resistance.

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Ambulatory Glucose Profile (AGP)

A clinician-friendly guide to the Ambulatory Glucose Profile (AGP) — what it shows, how to read the modal day.

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Amylase and Lipase Test: Pancreatic Enzymes for Diabetes

How amylase and lipase tests fit diabetes monitoring — pancreatitis screening, the GLP-1 and SGLT2 inhibitor concerns, and clinical indications.

Ankle-Brachial Index Test for Diabetes: PAD Screening

How ABI testing fits diabetes monitoring — peripheral artery disease screening, the simple painless procedure, and the diabetes-specific importance.

Best Blood Glucose Meter: How It Works, Accuracy, and How

The best blood glucose meter is accurate within FDA limits, uses affordable strips, and fits your daily routine. We compare the top options head to head.