What Are Normal Blood Sugar Levels After Eating?

Blood sugar levels after eating can be altered by a host of different factors. Unfortunately, an alteration in them can indicate the presence of some disease.
What Are Normal Blood Sugar Levels After Eating?

Last update: 02 July, 2023

The levels of sugar or glucose in the blood are the result of the intestinal absorption of nutrients and their metabolism within the body. They can be affected by diet, exercise, medications, and disease. Are you interested in knowing what normal blood sugar levels are after eating? In the following article, we’ll tell you.

Ingested food constitutes the main source of energy for the human body, as it determines the amount of sugars, fats, and proteins that the body has. However, some diseases can alter metabolism and change blood glucose concentrations.

Therefore, it’s vital to know what the normal glycemic characteristics are for the early diagnosis of these conditions.

Who should monitor blood sugar levels?

Blood sugar levels after eating can be measured with a glucometer.
Patients with metabolic problems, especially those with diabetes mellitus, should have regular control of their blood glucose levels.

Blood glucose concentration is a value with preventive, diagnostic, therapeutic, and prognostic properties. For this reason, patients with type 1 and type 2 diabetes are the main individuals who must maintain strict glycemic control. This is because diabetes is associated with multiple complications as a result of hyperglycemia.

Similarly, knowing fasting blood sugar levels and levels after eating favors the early detection of patients at high risk of diabetes. Such is the case of prediabetic people or people with glucose intolerance.

In addition, the relevance of glycemic control increases if you have relatives with diabetes or if you suffer from obesity and a sedentary lifestyle.

At the same time, the American Diabetes Association (ADA) estimates that routine blood sugar checking may be beneficial in other cases. In this regard, the following conditions stand out:

  • Patients with a regular prescription of insulin
  • People who use oral hypoglycemic agents
  • Pregnant women
  • Symptomatic and asymptomatic hypoglycemia
  • Those at risk of diabetic ketoacidosis

Normal blood sugar levels after eating

In general, postprandial blood glucose is one that which is obtained 1 to 2 hours after ingestion. It allows to us analyze the current state of glycemic metabolism and how it responds to the absorption of new nutrients. In this way, it’s possible to take timely diagnostic and therapeutic actions.

Today, blood sugar levels after eating can be measured using a glucometer or standard laboratory tests. This as part of a casual blood glucose or oral glucose tolerance test (PTOG).

Studies estimate that normal blood glucose levels 2 hours after ingestion in a PTOG are those below 140 milligrams per deciliter.

On the other hand, the recommended blood sugar levels in diabetics are those 180 milligrams per deciliter between 1 and 2 hours after eating. However, blood glucose requirements can change based on age, the length of the illness, and the presence of comorbidities.

Optimal postprandial glucose levels according to the type of patient

Target blood sugar levels after eating will vary based on a person’s age and health. In this regard, postprandial blood glucose should be found in the following values depending on the patient, expressed in milligrams per deciliter (mg / dl):

  • Children under 5 years of age without diabetes: Less than 250 mg / dl.
  • Children 6 to 11 years of age without diabetes: Less than 225 mg / dl.
  • Adolescents 12 to 18 years of age without diabetes: Less than 200 mg / dl.
  • Children and adolescents under 18 years of age with diabetes 2 hours after eating: 90 to 110 mg / dl.
  • Adults without diabetes 2 hours after eating: 90 to 180 mg / dl.
  • Adults with diabetes 2 hours after eating: Less than 180 mg / dl.
  • Diabetics who take insulin when eating: Less than 180 mg / dl.
  • Diabetics who don’t take insulin when eating: Less than 140 mg / dl.
  • Pregnant women with gestational diabetes 2 hours after eating: Less 120 mg / dl.
  • Pregnant women with previous type 1 or 2 diabetes, 2 hours after eating: Less than 110 or 120 mg / dl.

How does food increase blood sugar levels?

When ingesting food, a cascade of digestive enzymes is activated in the intestinal tract, which are responsible for breaking down the food into essential metabolites. In this regard, carbohydrates, proteins, fatty acids, vitamins, and minerals are obtained, which will be absorbed in the intestinal mucosa and pass into the bloodstream.

Carbohydrates are primarily responsible for raising blood sugar levels after eating. Research classifies carbohydrates into monosaccharides, disaccharides, oligosaccharides, and polysaccharides according to their chemical structure. Each of them has a different rate of intestinal absorption and impact on blood glucose.

For this reason, the elevation of blood glucose will depend on the type of food that’s being eaten. In the same way, it’ll be conditioned by the glycemic index that corresponds to each food. In this regard, if a meal has a high index, it’ll be absorbed faster, generating spikes in blood glucose.

On the other hand, if the index is low, the impact on blood glucose will be less. According to the ADA, the foods that have the greatest impact on sugar levels after eating are:

  • Bagels
  • Muffins and waffles
  • White bread
  • Processed cereals
  • Instant oatmeal and rice
  • Baked or boiled potatoes
  • Instant mashed potatoes
  • Sweetened and sports drinks

Lean sources of protein such as meat, poultry, and low-fat cheeses are recommended to reduce the impact of food on blood glucose. Additionally, healthy fats like peanut butter, walnuts, and olive oil promote the metabolic balance of nutrients.

Managing blood sugar

Currently, it’s possible to establish various measures and lifestyle changes that allow you to control blood glucose during the day and after eating. The aim is keeping sugar values within normal limits and reducing the risk of suffering from metabolic diseases or long-term health complications.

Blood glucose control and drug use

A woman giving herself an insulin shot in the belly.
Following the medical indications regarding treatment allows you to maintain blood glucose levels that are normal for each disease.

In prediabetic or diabetic patients, regular glycemic control is vital, especially if insulin is administered. In this way, it’s possible to take early preventive and therapeutic actions in the event of any significant variation in blood glucose.

At the same time, people must maintain strict monitoring of the medications and therapies prescribed by the specialist doctor.

Treatment of diabetes is aimed at promoting the lowering of blood glucose and increasing peripheral sensitivity to insulin. For this reason, metabolic fluctuations can appear if the drug is abandoned or isn’t used correctly.

Plate method

Diet is one of the key elements in managing plasma glucose levels. For this reason, it’s essential to establish an adequate diet plan that allows meeting the daily requirements without exceeding them. To do this, the plate method promotes a practical way to organize meals into healthy amounts and portions.

The first step is to select a medium-sized plate and mentally divide it in half into two equal portions. Then you must draw a horizontal line in the center of one of the halves to get three servings in all. In this way, each of these sections will be completed by a group or family of foods.

Non-starchy vegetables should fill the largest portion of the plate. This makes it possible to ensure the ingestion of a good amount of fiber, vitamins, and minerals.

In addition, an adequate amount of vegetables must be ensured in meals that can’t be divided into portions such as stews and soups. Some non-starchy vegetables that can be used include the following:

  • Tomatoes and peppers
  • Broccoli or cauliflower
  • Carrot and asparagus
  • Mushrooms and peas
  • Pumpkin, celery, and cucumber

At the same time, a section of the plate should contain lean, low-fat sources of protein. Studies affirm that its importance lies in the ability to provide amino acids that participate in the functioning and structure of cells. Among the most recommended protein sources are the following:

  • Chicken, eggs, and turkey
  • Fish and shellfish
  • Lean beef
  • Low-fat cheese
  • Beans and lentils
  • Tofu and tempeh

To finish, the last part of the plate must be filled with carbohydrates. It’s important to consider light foods that are rich in fiber, avoiding those that have the greatest effect on blood glucose, such as the examples mentioned above.

Ingested carbohydrate count

In high-risk patients with obesity, diabetes, and prediabetes, a good option is to calculate carbohydrates ingested in grams.

For type 1 and type 2 diabetics who consume insulin at mealtime, the carbohydrate-insulin ratio (ICR) is established. It defines the volume in grams of carbohydrates that 1 unit of insulin covers and is individualized per person.

A practical way to count carbohydrates is to read the nutritional chart that comes with most foods. From this information, the amount of carbohydrates you eat is calculated based on weight or serving size. In this way, you’ll have a clear notion of how many carbohydrates enter the body each day.

The amount of carbohydrates that should be eaten isn’t specific and will depend on several factors. These include age, basal metabolism, weight, height, physical activity, and the patient’s health status. For this reason, it’s advisable to go to a nutritionist to establish an adequate diet plan.

Nutritional therapy

Today, medical nutrition programs and services allow professional support to be provided with the goal of achieving healthy changes in the diet and lifestyle of patients. In this way, it seeks to establish in people the principles of a healthy and balanced diet in the long term.

Similarly, nutrition professionals seek to detect existing metabolic diseases in time. In addition, the goal is to guide and educate people to choose foods based on their health, daily requirements, and physical activity.

Normal blood sugar levels can vary

The state of the human body is the result of individualized adaptive mechanisms. For this reason, normal blood sugar levels throughout the day and after eating can vary from one person to another, which promotes the estimation of normal ranges.

The goal of health care is for the patient to stay within that ideal blood glucose range to avoid possible adverse effects and complications. In addition, it should be taken into account that other factors such as stress, physical activity, and the use of medications can condition or alter blood sugar values.



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