What You Should Know About Glucose and Dextrose

Sugar can get a bad rap. And sure, most of us could do with a little (or, let’s face it, a lot) less. But we need sugars like glucose for critical thinking and other brainy activities. In fact, your brain uses half the sugar in your bloodstream (also called blood glucose) to help your body work properly.

You can get glucose from foods. Or your body can make its own through a process known as gluconeogenesis. “Glucose is your body’s main fuel source,” says diabetes educator Megan Asterino-McGeean, BSN, RN. “It feeds cells, giving your brain and muscles much-needed energy.”

Another similar sugar, dextrose, also keeps your brain and body humming along.

Asterino-McGeean shares what you should know about these two important sugars.

Glucose vs. dextrose

Glucose and dextrose are both simple sugars (monosaccharides) with slightly different chemical makeups. “But there isn’t much difference between these sugars,” notes Asterino-McGeean, “which is why the two terms are often used to mean the same thing.”

What is glucose?

Glucose is a monosaccharide found in foods and drinks that have carbohydrates. Your body also makes glucose when it breaks down carbohydrates. “Mainly your liver, but also brain and muscle cells, store unused glucose as glycogen,” says Asterino-McGeean. “When you need an energy boost or your blood sugar drops too low, your body breaks down the glycogen into glucose for fuel.”

Glucose can attach with other simple sugars to form:

• Lactose (glucose plus galactose).
• Maltose (two linked glucose molecules).
• Sucrose (table sugar) and high fructose corn syrup (glucose plus fructose).

What foods have glucose?

Foods and drinks with carbohydrates provide glucose. These include:

• Bread, rice and pasta, including whole-grain products.
• Fruits and vegetables.
• Sugary drinks like soda.
• Sweets like candy, cookies and desserts.

What is blood glucose, or blood sugar?

Your blood glucose level is how much sugar is in your blood. For your body to use sugar effectively, your pancreas makes a hormone called insulin that moves glucose from your blood into your cells. How well your body makes or uses insulin affects the amount of glucose in your blood, also known as blood sugar.

High blood sugar conditions

Some people have blood sugar levels that are higher than normal. High blood sugar (hyperglycemia) can be a sign of a health issue, such as:

• Insulin resistance occurs when cells in your muscles, fat or liver can’t take in or store glucose as they should. Your pancreas churns out more insulin, causing high insulin levels (hyperinsulinemia).
• Prediabetes is when your blood sugar is higher than it should be but not high enough for a diabetes diagnosis. Prediabetes is a warning sign that you’re at risk for diabetes.
• Diabetes occurs when your body can’t make insulin (Type 1 diabetes) or use insulin properly (Type 2 diabetes). “Glucose stays in the bloodstream instead of moving into cells,” explains Asterino-McGeean. “Your blood sugar levels get too high.”

Causes of low blood sugar

It’s also possible for blood sugar levels to get too low. Causes of low blood sugar (hypoglycemia) include:

• Alcohol or high sugar intake (reactive hypoglycemia).
• Fasting, not eating enough or skipping meals.
• Insulin medications.
• Overexercising.
• Pregnancy.

Glucose and the glycemic index

The glycemic index measures how much and how quickly a carbohydrate can raise your blood sugar. “Typically, foods high on the index have the potential to raise glucose at a faster rate,” says Asterino-McGeean. “The index reflects the complexity of carbohydrates — they are not all the same.”

Simple carbohydrate foods like candy and soda are high on the glycemic index. Your body quickly breaks down simple carbs into glucose, causing a spike in blood sugar.

But it’s important to remember that every body is different. This means that your glucose levels will react differently to each source of carbohydrate.

Whole-grain products, as well as vegetables, are complex carbohydrates. They are usually lower on the glycemic index. “Because it takes longer for your body to break down complex carbohydrates, blood sugar levels increase gradually,” says Asterino-McGeean. “Your cells benefit from a steady source of energy.”

How do you measure blood sugar?

A blood glucose (sugar) test measures glucose in your blood. Most people get this test as part of their annual physical. People with diabetes may get more frequent blood tests called A1C tests.

“An A1C test gives an average measure of blood sugar levels over a three-month period,” says Asterino-McGeean. “A higher number or percentage indicates higher blood sugar levels during the past three months.”

People with diabetes must monitor their blood sugar levels daily. A continuous glucose monitor uses a sensor underneath your skin to measure blood sugar 24/7. Some people prefer to use a small needle called a lancet to draw blood from a finger. With a finger stick test, a glucose meter measures the amount of blood sugar in a blood droplet.

Managing blood sugar

There are many tools to manage diabetes and high blood sugar:

• Follow a diabetes-friendly diet.
• Make lifestyle changes.
• Use insulin therapies, such as oral medications, subcutaneous injections or insulin pumps.

What is dextrose?

Dextrose mostly comes from corn and wheat. Food manufacturers may add dextrose to:

• Make foods shelf stable.
• Promote fermentation, such as with wine.
• Sweeten foods.
• Take the bite out of foods that are too spicy or salty.
• Toast (brown) baked goods.

What foods have dextrose?

You may find dextrose in these foods:

• Canned foods.
• Crackers.
• Cured meats.
• Fruit jam.
• Pickles.
• Potato chips.
• Sauces.
• Seasoning mix.

Other uses of dextrose

You may also find dextrose in:

• Bath products.
• Hair products.
• Makeup.
• Skin care products.

What are the benefits of dextrose?

Dextrose is a high-glycemic food that raises your blood sugar levels. This can be unhealthy if you have diabetes. But it’s good if you need to raise severely low blood sugar levels quickly.

You might be surprised to learn that dextrose has medical uses, too. Healthcare providers use dextrose to treat:

• Dehydration: People experiencing severe dehydration may receive an IV solution of dextrose and saline (sterile salt water).
• Low blood sugar: Foods and drinks with dextrose, like canned fruit or fruit juice, can quickly raise blood sugar that’s dangerously low. People with diabetes who are prone to episodes of low blood sugar may take dextrose tablets to bring blood sugar to a healthy level.
• Malnutrition: People experiencing malnutrition may receive an IV nutrition solution that has dextrose.

Bodybuilders and those who strength train sometimes use dextrose to help repair muscles and tissues. Dextrose tablets or supplements replenish the stored sugar your body burns through during a strenuous workout. Talk to a healthcare provider if you think a dextrose tablet may help you.

Is glucose or dextrose bad for you?

Glucose and dextrose can do your brain and body good — as long as you don’t overdo it. Too much sugar of any kind raises your risk for diabetes and these health issues:

1. Weight gain

Many Americans consume more than 300% of the recommended daily amount of added sugar. An excess of sugar means a surplus of calories. Studies show a strong link between consuming high-sugar foods and weight gain. You’re more likely to have belly fat or obesity.

2. Heart problems

Your body changes unused glucose and dextrose into fatty substances called lipids. Your liver stores these lipids, which include cholesterol and triglycerides. The more sugar in your diet, the higher your triglycerides, according to study findings. High lipids can lead to inflammation and high cholesterol. All of these factors raise your risk of heart disease.

3. High blood pressure

Salt isn’t the only additive that raises blood pressure. Too much sugar can also cause these numbers to climb. One study reported that females between ages 65 and 80 who reduced their sugar intake by 2 teaspoons saw a noticeable drop in blood pressure.

How much glucose or dextrose can you have in a day?

There aren’t set guidelines for how much sugar — of any kind — is OK to have every day. Still, the U.S. Department of Agriculture (USDA) dietary guidelines recommend limiting added sugars like glucose and dextrose to less than 10% of total calories. This means someone on a 2,000-calorie diet should get no more than 200 calories from added sugar. That’s approximately 12 teaspoons of sugar per day.

“Sugar isn’t the enemy. But it can be a bit of a troublemaker, especially if you have diabetes or other health issues,” clarifies Asterino-McGeean. “Be mindful of how much sugar you have every day. If you’re getting too much, it can be very helpful to take steps to manage sugar cravings.”