More than 30 million Americans have diabetes — that’s 9.4 percent of the population! If you’ve already been diagnosed with diabetes or are at risk for developing it, you’re far from alone.

Random glucose testing is a tool to help doctors and patients identify a problem with blood sugar control and manage diabetes, so life is sweet — but not too sweet.

This will only hurt a little, I swear

All it takes is a quick prick of your finger to start a random glucose test. A drop of blood is applied to a test strip to measure how much glucose (aka sugar) is in your blood.

The test is usually done in a doctor’s office if a person has symptoms or is at risk for developing diabetes. People with diabetes may also do random glucose tests at home to see how well they’re managing the condition.

Why is there sugar in my blood, anyway?

When you eat anything — from pizza to yogurt to a giant kale salad — that food is broken down into a sugar called glucose which then enters your bloodstream. The hormone insulin (released by the pancreas) is like a key, unlocking cells so glucose can get in there and fuel all the work your body does just to keep you alive.

If there’s no insulin to unlock cells, or if cells start to resist insulin — like “no buddy, back off!” — glucose builds up in the bloodstream. When glucose builds up in the bloodstream, high blood sugar (aka hyperglycemia) occurs.

T1 vs. T2

Type 1 diabetes: An autoimmune disease that destroys insulin-making cells called islets. Type 1 diabetes accounts for about 5 percent of all diabetes cases. People with type 1 (usually diagnosed in children, teens, and young adults) need to take insulin injections.

Type 2 diabetes: This type happens when the body continues to produce insulin, but cells become resistant to it. High levels of glucose build up in the blood if not managed by medications, exercise, and diet.

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What about low blood sugar? That’s a thing, right?

Unlike hyperglycemia, hypoglycemia occurs when glucose in the blood falls too low. This can happen when you don’t eat enough, drink alcohol on an empty stomach, take too much insulin, or exercise more than usual.

A random glucose test quickly reveals if blood glucose is above the normal range. The test can be done at any time, no fasting is required.

Here are some other tests that may be ordered by your doctor, though they aren’t as quick or convenient as a random glucose test:

Fasting glucose test — basically the same test, but you’re hungry

If a doctor suspects you may have diabetes, they may ask you to come in for a blood test when you’ve had nothing to eat or drink for at least 8 hours besides water (it’s usually first thing in the morning, so it’s not as cruel as it sounds).

This test will show if extra sugar is floating around in your veins even when you haven’t eaten anything to spike your glucose levels. High fasting glucose is a sign that insulin isn’t behaving like it should.

The OG: Oral glucose tolerance test (OGTT), that is

An Oral Glucose Tolerance Test (OGTT) is a much longer time commitment, but fasting isn’t required. The doctor will measure blood sugar before and then 2 hours after you consume a very sweet drink containing a specific amount of glucose.

Rather than giving a single reading for one point in time, the OGTT shows how your body responds to a controlled amount of sugar over time.

If you’ve noticed these signs of diabetes, it’s time to call your healthcare provider. Your doctor may want to do a random glucose test if you:

  • wake up to pee in the middle of the night
  • can’t go anywhere without your water bottle because you’re so thirsty
  • jeans feel loose even though you’re not trying to lose weight
  • are way more hungry than usual
  • vision is blurry
  • hands and feet feel tingly
  • feel exhausted
  • skin is super dry
  • cuts and sores take forever to heal
  • experience frequent infections
  • thick, dark, velvety skin around your neck or armpits (aka acanthosis nigricans)

Or, if you fall into one or more of these at-risk categories associated with developing prediabetes or type 2 diabetes:

  • have a larger body
  • are age 45 or older
  • have a parent, brother, or sister with type 2 diabetes
  • are physically inactive
  • have had gestational diabetes or have given birth to a baby weighing more than 9 pounds
  • are American Indian, Native Alaskan, Pacific Islander, Native Hawaiian, Asian American, Hispanic/Latino, or African American.

Type 2 diabetes can sneak up on you, with symptoms developing so slowly you don’t notice. Getting answers (and a diagnosis) early means more time to make healthy lifestyle changes like increasing activity (a reliable way to burn sugar).

If the result of your random glucose test is over 200 mg/dL, you have diabetes. Doctors will usually do two tests at different times to confirm a diagnosis.

A normal fasting (no food or drinks other than water for 8 hours) glucose reading is under 100 mg/dL. So, for a fasting test, if your blood glucose is 100 to 125 mg/dL you’re in the prediabetes category, and over 125 mg/dL means you have diabetes.

If 2 hours after drinking the glucose beverage during an Oral Glucose Tolerance Test, your blood sugar reading is over 200 mg/dL, that indicates diabetes. A reading of 140 mg/dL or lower is considered normal.

If you have diabetes, that is. For a person without diabetes, insulin does its job and blood glucose levels stay within the normal range, no matter how much they eat or exercise. When you have diabetes, insulin is either AWOL or not doing a good job, so blood sugar rises.

Spikes in glucose can be caused by the foods you eat, inactivity, taking too little insulin or diabetes medication, side effects of other medications, illness, stress, pain, menstrual cycles, poor sleep, or dehydration.

That’s a lot, right? It’s important to note what else is going on when tracking blood sugar to get the big picture.

Your body is basically a majestic sugar fire

Exercise is a pretty reliable way to burn off high blood sugar and lower that reading. Whether it’s walking, swimming, or lifting weights, muscles need fuel to work. While you exercise, your muscles are using up the extra glucose in your blood.

Study tips for the best test results

Follow these tips to get the most accurate and useful glucose readings.

  • Wash your hands before testing. You don’t want a contaminated sample!
  • Keep it fresh — check the expiration date on your test strips.
  • Take note of when and what you ate most recently.
  • Have you had any alcoholic drinks? Make a note of that too, because alcohol can cause glucose to spike or drop.
  • Write down what type of exercise you’ve done and when.
  • Note changes in your medication.
  • If you’re feeling physically unwell for any reason, that will also affect blood sugar.
  • Don’t ignore stress (physical or emotional) — it causes blood sugar to go up. Consider this an adequate excuse to focus on self-care.
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Your diabetes treatment plan may call for checking blood sugar at the same time(s) every day, such as first thing in the morning or 2 hours after a meal.

Along with those scheduled readings, random glucose testing can give you extra insight into how well you’re managing diabetes.

Blood glucose will vary throughout the day, but unusual variations might be explained by some of the other details you’ve logged. Talk to your healthcare provider about ways to achieve better control.

It’s a catch-22 though, right? Having diabetes stresses you out, and stress screws up your blood sugar. Try to chill and remember that knowledge is power. You’ll learn what keeps your numbers in the ideal range, and by using this information you can kick diabetes to the curb.

Be on the lookout for these signs of hyperglycemia (high blood sugar): thirst, fatigue, headache, difficulty concentrating, and frequent urination. Feeling off? Do a random glucose test.

What’s the big deal?

Unmanaged diabetes and high blood sugar can lead to some pretty gnarly complications. According to the CDC, people with diabetes are twice as likely to have heart disease or stroke than people without diabetes.

Other serious complications from diabetes include kidney disease, amputation, and blindness.

The best way to prevent these scary complications is to test your blood sugar regularly and follow a treatment plan to keep glucose in the target range recommended by doctors.

  • Diabetes is a chronic disease in which the body doesn’t produce or doesn’t respond to insulin efficiently.
  • Without insulin to “unlock” cells, glucose builds up in the bloodstream, causing damage and complications over time.
  • A random glucose test is a quick and simple way for people who are at risk for diabetes to get one step closer to a diagnosis.
  • With just a drop of blood and a glucose meter, doctors can see if your blood sugar is in the normal range. If not, a diagnosis is the first step to building a treatment plan that can help you live well with diabetes.