What Are Normal Blood Sugar Levels for People Without Diabetes?

Find out what normal glucose levels are for non diabetics, what to do when glucose spikes and more.

woman wearing a continuous glucose monitor holding a smart phone and looking at it
Caitlin Beale, MS, RDN
— Signos
Health & Nutrition Writer
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Updated by

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Science-based and reviewed

May 28, 2023
August 11, 2021
— Updated:
June 21, 2022

Table of contents

Many people think of blood sugar as something that only people with diabetes need to think about, but the truth is that everyone can benefit from knowing their blood glucose levels.

Diabetes is often called a silent disease because there aren’t many symptoms, especially in the beginning. You can have high blood sugar or insulin resistance for years before even developing diabetes. Blood sugar dysregulation and higher insulin levels can make it harder to lose weight, impact energy levels, and even affect your mood.

This article will help you understand normal glucose ranges, why blood sugar matters for your health, and what steps you can take to keep your blood sugar stable.

<p class="pro-tip"><strong>Learn more about </strong><a href="/blog/benefits-stable-glucose">the benefits of stable blood sugar</a></p>

Blood Sugar and Diabetes

To better understand what's considered normal for blood sugar levels, it helps to know what happens when blood sugar is out of range and why it happens.

Diabetes occurs when your pancreas can't make enough insulin to move sugar out of your blood, or your cells become less responsive to insulin.

Insulin is a hormone that tells your body to move glucose out of the blood and into your cells. Once inside your cells, glucose can be used for energy or stored as fat. People with diabetes aren't able to lower blood sugar effectively, so it remains higher than what's considered normal.

Abnormal blood sugar occurs when too much or too little sugar is in the blood.

  • Hypoglycemia (also known as low blood sugar) is 70 mg/dL (3.9 mmol/L) or less.
  • Hyperglycemia (also known as high blood sugar) is 180 mg/dL (10.0 mmol/L) or more.

There are four tests used to test blood sugar levels. Blood glucose, aka blood sugar, is measured in milligrams per deciliter (mg/dL):

  • Hemoglobin A1c: A1c measures long-term blood sugar averages over two to three months. Anything about 6.5% is considered a diagnosis of diabetes. This plus fasting (see below) are most commonly used.
  • Fasting blood sugar: Fasting blood sugar looks at glucose levels before you've eaten anything. Fasting glucose above 126 mg/dL is also considered diabetes.
  • Casual or random plasma glucose test. As the name suggests, this test randomly tests your blood sugar at any time and doesn't require fasting. Anything higher than 200 mg/dL is considered diabetes.
  • Oral glucose test. Often used in pregnancy, this requires drinking a specific amount of glucose and testing glucose at one, two, and sometimes hours after. Higher than 200 mg/dL after two hours indicates diabetes.

<p class="pro-tip"><strong>Learn more about </strong><a href="/blog/what-is-a-continuous-glucose-monitor">how a continuous glucose monitor works</a></p>

What Are Normal Blood Glucose Levels for People With Diabetes?

People with diabetes will often have higher blood sugar targets or “acceptable” ranges than those without the condition, although these levels can also vary individually depending on a person’s treatment goals.

According to the American Diabetes Association, target blood sugar levels for people with diabetes are:

  • Before eating: 80–130 mg/dL (4.4–7.2 mmol/L)
  • One to two hours after eating: <180 mg/dL (10.0 mmol/L)

What Are Normal Blood Glucose Levels for People Without Diabetes?

Normal blood glucose ranges for people without diabetes are:

  • Fasting: 70-99 mg/dL
  • 1-2 hours after a meal: less than 140 mg/dL

<p class="pro-tip"><strong>Learn more about </strong><a href="/blog/blood-sugar-spikes-exercise">how exercise can affect blood sugar levels</a></p>

Most blood sugar charts show recommended levels as a range, allowing for differences between individuals. Some people may find they have much lower blood sugar while others hover a bit higher, but the ranges above are considered diagnostic cut-offs by medical professionals.

Note: The Signos app uses a slightly different range to support weight loss, as you’ll learn about more below.

women sitting on some steps outdoors with a small white dog, eating food and laughing
Understanding how food affects your blood sugar levels can also benefit people without diabetes.

Does a Blood Sugar Spike Mean You Have Diabetes?

Occasional high spikes don’t mean you have diabetes. It’s normal for your blood sugar to go up after eating a meal high in carbohydrates or even due to lifestyle habits and events. Besides food, your blood sugar can be affected by stress, lack of sleep, age, menstrual cycle, physical activity, and even being sick.

What affects one person's blood sugar may also affect yours differently. We can all have different responses to food, so monitoring the overall trend of your blood sugar gives you the most insight into your overall health. 

However, while infrequent spikes aren't a problem, if they happen more regularly, it's time to take a closer look at what's contributing.

<p class="pro-tip"><strong>Learn more about </strong><a href="/blog/mitigate-high-glucose-spikes">how to mitigate glucose spikes to avoid fat storage</a></p>


Why Elevated Glucose May Lead to Weight Gain

Foods high in sugar and refined carbs may promote weight gain because of their impact on blood sugar and insulin levels. These foods are considered high-glycemic carbs because they are quickly digested and lead to rapid rises in blood sugar.

Examples of high-glycemic foods include:

  • White bread, bagels, white rice, white-flour pasta
  • Muffins, croissants, doughnuts, flavored instant oatmeal, most cereals
  • Cakes, candy, cookies, and most desserts
  • Corn and white potatoes

<p class="pro-tip"><strong>Learn more about </strong><a href="/blog/foods-to-avoid-for-weight-loss">8 foods to avoid for weight loss</a></p>

Occasionally eating some cake at a birthday party isn't a big deal, but a diet high in these foods and low in other blood sugar balancing nutrients like fiber and protein can mean you have higher insulin levels than usual as your body tries to lower blood sugar. Over time, insulin can promote fat storage.

When your glucose spikes and you don't burn the excess energy, your body converts the extra glucose to glycogen stored in your muscle tissue and liver or as fat stored in your adipose (fat) cells.

By preventing your glucose from spiking too often, you can limit the flood of insulin from your pancreas and access energy from your stored body fat more efficiently. 

By learning how your blood sugar responds to food and exercise, you can keep your glucose in a target range that also promotes a healthy weight.

<p class="pro-tip"><strong>Learn more about </strong><a href="/blog/ultra-processed-foods">how ultra-processed foods affect blood sugar</a></p>

baked goods including muffins and pastries
High-glycemic foods like pastries are typically low in fiber and can cause spikes in blood glucose levels.

Tips For Signos Users

After applying a continuous glucose monitor (CGM) and calibrating, you'll see your blood sugar levels, also known as your glucose, in the Signos app for the first time. You should also see the general suggested glucose range target for weight loss.

Over the next few days, as the app calibrates your individual optimal glucose range for weight loss. For Signos, the ranges look like the following (remember these are different than the diagnostic levels discussed above):

  • Fasting glucose target: 72-90 mg/dL
  • Glucose target before eating: Depends on what you ate, what you did, and what you plan to eat
  • Glucose target 1-2 hours after eating: <120 mg/dL

The best way to use your Signos app is to perform self-experiments—because everyone is so different. As you read above, research shows that meals higher in protein, fiber, and fat can help slow down and decrease the post-meal blood sugar response.

Try eating a high-protein meal with some healthy fat and fiber to see how your blood sugar responds. Then compare it to a high-carb meal. You can even vary the amounts of protein, fat, and fiber on different days to see if it makes a difference.

<p class="pro-tip"><strong>Learn more about </strong><a href="/blog/cgm-data-weight-loss">using a CGM to analyze your unique glucose response</a></p>

Frequently Asked Questions

What should my blood sugar be 1 hour after eating?

A person without diabetes should have a blood glucose level less than 140 milligrams per deciliter (mg/dL) one to two hours after eating.

What should my blood sugar be 3 hours after eating?

A person without diabetes should drop close to fasting levels, usually below 125 milligrams per deciliter (mg/dL) three hours after eating.

What is a good blood sugar level in the morning?

Your blood sugar should be between 70 to 99 mg/dL in the morning before eating anything.

What levels of blood sugar are dangerous?

Fasting blood sugar levels above 100 indicate prediabetes, and anything above 126 is considered diabetes.

Does blood sugar rise with age?

Blood sugar rises as you age, possibly related to insulin resistance or the pancreas making less insulin.

<p class="pro-tip"><strong>Learn more about </strong> <a href="/blog/what-factors-affect-blood-sugar">factors that can affect your blood sugar (besides food)</a>.</p>

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Topics discussed in this article:


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About the author

Caitlin Beale is a registered dietitian and nutrition writer with a master’s degree in nutrition. She has a background in acute care, integrative wellness, and clinical nutrition.

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