Start with the basics: an A1C or fasting blood sugar test, your waist size, blood pressure, and the triglycerides and HDL on a cholesterol panel. Together they show which way your metabolism is heading. Fasting insulin, a body scan and a glucose monitor can add detail, but they work best as extras, not as a starting point.
The tests, in plain English
Think of insulin as a key that lets sugar out of your blood and into your cells. When the locks get stiff, your body makes more keys to keep up, and your blood sugar can look normal for years while it does.
A1C
Shows your average blood sugar over the past two to three months, so one big meal won't skew it. No fasting needed. It's one of the standard tests for prediabetes and diabetes.
For: Adults from their mid-thirties with extra weight, or anyone with risk factorsFasting blood sugar
Measures the sugar in your blood after a night without food. It's quick and often part of a routine blood draw. A high result is usually repeated before anyone calls it a diagnosis.
For: Adults from their mid-thirties with extra weight, or anyone with risk factorsGlucose tolerance test
You have a sugary drink, then your blood is checked over the next couple of hours. It shows how well your body clears a load of sugar. It takes a morning, so it's used less often than the other two.
For: Usually when a doctor wants a closer lookTriglycerides and HDL
Two numbers from a standard cholesterol panel. High triglycerides and low HDL, along with a larger waist and higher blood pressure, are part of the cluster doctors call metabolic syndrome. You may have had them checked already.
For: Every adultFasting insulin
Measures how much insulin your body needs to hold blood sugar steady. A high level may hint at insulin resistance before your blood sugar rises. Labs measure it differently, there's no agreed normal range, and it isn't used to diagnose anything.
For: Anyone wanting a closer look, alongside the standard testsWaist and body composition
A tape measure around your waist is the simple version. A DEXA scan, a low-dose X-ray, goes further and estimates the fat stored deep around your organs, which is closely linked to blood sugar problems.
Cash price: $65 to $249
For: Anyone who wants more than a tape measureContinuous glucose monitor
A small sensor on your arm reads your blood sugar around the clock for up to about two weeks. It shows how food, sleep and exercise affect you. Good for learning, but talk to a doctor before acting on it.
For: People with prediabetes, or curious about their patternsPrices that clinics publish on their own websites, across all the cities we cover. Prices change, so confirm with the clinic.
Blood sugar in Los Angeles, by the numbers
The rate of diagnosed diabetes in Los Angeles is about the same as the national rate. About 1 in 8 adults in Los Angeles have been diagnosed with diabetes, compared with about 1 in 8 nationally. That adds up to roughly 970,000 adults in Los Angeles County.
CDC estimates. PLACES figures are modelled from a national health survey, not counted from medical records, so read them as estimates.
Source: CDC PLACES, 2023 county estimates. Los Angeles = Los Angeles County, weighted by adult population.
longevityclinicshub.comThe good news: prediabetes often doesn't have to become diabetes. That's why the simple tests above are worth doing early, even when you feel fine.
