Blood glucose levels 1 hour after eating

Diabetes affects more than 1 in 10 Americans, yet it can still feel like an unclear and complicated illness to manage. One of the best ways to better understand your diabetes is by regularly checking your blood glucose levels. But what makes your blood glucose levels change? And when is the best time to check it especially around mealtimes? Here we answer those questions and more.

a woman checking her glucose levels

Credit: Getty Images

What causes your blood glucose to go up?

Blood glucose (also referred to as blood sugar) refers to the amount of glucose that is circulating through your blood, ideally headed to cells for energy. Insulin is the hormone that allows glucose into our cells, but those with type 1 diabetes don't produce insulin and those with type 2 diabetes are resistant to insulin and don't use it effectively.

Things that can make our blood glucose levels go up include food, stress and illness. Things can can cause our blood glucose levels to go down can include long periods of time without eating, taking too much medication (like insulin) and physical activity.

Each person, regardless of whether they have diabetes, has their own healthy blood sugar target range where their body functions as its best. If you have diabetes, it's important to identify what your range is, and how it compares to a range that would make you feel your best. Talk with your healthcare team about your current range as well as what the healthiest range for you would be.

Related: How Often to Test Your Blood Glucose

When is the best time to check your blood glucose after a meal?

Measuring your blood glucose after a meal is important because that is typically when our blood glucose levels are at their highest. Food takes some time to be broken down into usable energy, but most of the food you consume will be digested and raise your blood glucose in one to two hours. To capture the peak level of your blood glucose, it is best to test one to two hours after you start eating.

The American Diabetes Association (ADA) recommends a target of below 180 mg/dL two hours after a meal. The American Association of Clinical Endocrinologists recently updated their guidelines to match those of the ADA.

Post-meal blood glucose monitoring (and record-keeping) is important because it helps you see how your body responds to carbohydrates in general, and also how you respond to particular foods. Managing post-meal blood glucose can help reduce your risk of developing other complications associated with diabetes, such as heart and circulation problems.

Diabetes impacts your body’s ability to control your blood sugar (glucose) levels. Uncontrolled blood sugar can lead to serious complications, which is why monitoring your blood sugar and keeping it within recommended ranges is so important.

Your recommended blood sugar range can be impacted by a variety of factors such as your age, overall health, and diabetes management goals.

The charts in this article will help you understand the recommended ranges for blood sugar as well as for A1C.

Recommended blood sugar ranges

Recommended blood sugar levels can help you determine whether your blood sugar is in a “normal” range.

However, your blood sugar target level may vary from the general recommendation due to:

• your overall health
• your age
• the presence of other health conditions (known as comorbidities)
• the length of time you’ve had diabetes

A doctor or healthcare professional will let you know what the target range should be for you, based on your health and medical history.

Recommended blood sugar range for adults with type 1 and type 2 diabetes and children with type 2 diabetes

According to the American Diabetes Association, these ranges are recommended for adults with either type 1 or type 2 diabetes and for children with type 2 diabetes:

TimeRecommended blood sugar rangeFasting (before eating)80–130 mg/dL1–2 hours after a mealLower than 180 mg/dL

Ranges are adjusted for children under 18 years with type 1 diabetes, pregnant people, and people with gestational diabetes, as outlined in the charts below.

Blood sugar range for children under 18 years with type 1 diabetes

The chart below shows the recommended blood sugar range for children under 18 years with type 1 diabetes.

TimeRecommended blood sugar rangeFasting (before eating)90–130 mg/dLBedtime and overnight90–150 mg/dL

Recommended blood sugar range for pregnant people with type 1 diabetes

TimeRecommended blood sugar rangeFasting (before eating)Lower than 95 mg/dL1 hour after a meal140 mg/dLor less2 hours after a meal120 mg/dL or less

Blood sugar range for people with gestational diabetes

TimeRecommended blood sugar rangeFasting (before eating)Lower than 95 mg/dL1 hour after a meal140 mg/dL or less2 hours after a meal120 mg/dL or less

Recommended blood sugar if you don’t have diabetes

For people without diabetes, the standard blood sugar range is the same, regardless of age or health condition. However, a doctor may set different goals based on your specific circumstances.

For instance, if you have several risk factors for diabetes, a doctor might want your blood sugar to be within a tighter range.

Thestandard blood sugar rangefor people who don’t have diabetes is outlined in the chart below.

TimeRecommended blood sugar rangeFasting (before eating)99 mg/dL or below1–2 hours after a meal140 mg/dL or below

What about A1C?

AIC is a measure of your average blood sugar over the past 3 months. To have your A1C measured, you’ll need a blood draw.

When sugar enters your bloodstream, it binds to a protein called hemoglobin. People who have high blood sugar have a higher percentage of the hemoglobin protein coated with sugar. Your A1C result will give you an indication of what percentage of your hemoglobin is bound to sugar.

In the chart below you can see whether your A1C result falls into a “normal” range or whether it could be a sign of prediabetes or diabetes.

DiagnosisA1C resultStandard (“normal”)Less than 5.7%PrediabetesBetween 5.7% and 6.5%DiabetesMore than 6.5%

It’s generally recommended that people with any type of diabetes keep their A1C below 7 percent.

However, other health conditions and health goals might change this. A doctor will let you know whether, based on your unique factors, you have a different A1C goal.

Why should you measure your blood sugar?

Keeping track of your

Careful monitoring of your blood sugar and knowing what may cause it to rise or fall can help you and a health team develop a diabetes care plan and set treatment goals.

Additionally, measuring your blood sugar can help you:

• monitor how medications are impacting your blood sugar levels
• determine how different meals and food choices impact your blood sugar
• determine whether exercise or other lifestyle changes are impacting your blood sugar levels
• keep track of your overall progress

Even if you don’t have diabetes, it’s a good idea to get your blood sugar checked periodically. A doctor might order a blood sugar test as part of an annual physical. If you have any risk factors for diabetes, you may need to get your blood sugar checked more often.

How to lower your blood sugar

High blood sugar levels, known as hyperglycemia, can make you feel tired or thirsty and can even make your vision blurry. Many factors can cause a spike in your blood sugar, including:

• stress
• illness
• taking too little insulin
• eating large meals or eating more carbohydrates than usual
• being less physically active than usual

Over time, high blood sugar can lead to serious complications such as:

• nerve damage
• kidney damage
• eye complications

Fast-acting insulin

If your blood sugar is higher than recommended, you can bring it down by taking fast-acting insulin. Talk with a doctor about how much insulin you should take if your blood sugar is above a certain level.

However, you’ll want to be sure that you take into account any insulin you may already have in your body. Some types of insulin can take several hours to be fully absorbed, so you’ll want to avoid taking too much insulin if you still have some that hasn’t taken effect yet. This could cause your blood sugar to drop too low.

You’ll want to check your blood sugar within 15 to 30 minutes after administering insulin to make sure your blood sugar is coming down but not dropping too low.

Exercise

Another effective way to lower your blood sugar is to exercise. When you’re physically active, your body uses up excess glucose in your blood. However, if you have severe hyperglycemia, you should avoid exercise as it can speed up ketoacidosis, a potentially life threatening condition.

Talk with a healthcare professional if you’ve been having frequent spikes in your blood sugar levels. They may want to adjust your medications or work with you to develop a different diet plan.

How to raise your blood sugar

Low blood sugar is defined as blood sugar below 70 milligrams (mg) per deciliter (dL). If your blood sugar drops too low, you might feel:

• dizzy or light-headed
• shaky
• hungry
• irritable
• tired
• unable to focus or concentrate

If your blood sugar stays low, you can become confused and have trouble speaking and seeing. Blood sugar that stays low for a longer period of time can lead to serious complications such as a coma or seizures.

The rule of 15

Low blood sugar is more common in people with type 1 diabetes. It’s recommended that you treat low blood sugar using the “15-15 rule.” You do this by following these steps:

1. Consume 15 g of carbohydrates and wait 15 minutes.
2. After 15 minutes, test your blood sugar.
3. If your blood sugar rises above 70 mg/dL, you can stop.
4. If your blood sugar is still below 70 mg/dL, consume another 15 g of carbohydrates and wait another 15 minutes.
5. Repeat these steps until your blood sugar returns to normal.

You can get 15 g of carbohydrates from 4 glucose tablets, half a cup of juice or regular soda, or a tablespoon of honey.

Let a doctor know if your blood sugar regularly falls too low. You might need to change the type or amount of insulin you take or the time at which you take it.

It’s also a good idea to make a note of the symptoms you experience during a low blood sugar episode and how long it takes for your blood sugar to recover. This information can help a doctor develop the right type of care plan for you.

The bottom line

Monitoring your blood sugar is a key part of diabetes management. Blood sugar levels that consistently fall within the recommended ranges are a sign that your medications, diet, and other diabetes treatments are working well.

Blood sugar ranges are general guidelines. You might have a slightly different recommended blood sugar range depending on your overall health, age, the length of time you’ve had diabetes, and other factors.

If your blood sugar levels frequently spike too high or drop too low, talk with a healthcare professional about making a change to your diabetes management plan.

Is blood sugar higher 1 hour or 2 hours after eating?

What is a normal blood sugar spike after eating?