Simple sugars are a type of carbohydrate. Carbohydrates are one of the three basic macronutrients — the other two being protein and fat.
Simple sugars are found naturally in fruits and milk, or they can be produced commercially and added to foods to sweeten, prevent spoilage, or improve structure and texture.
This article explains the different types of simple sugars, how to identify them on food labels, and how they can affect your health.
Carbs are molecules that contain single, double, or multiple sugar molecules called saccharides (1).
They supply four calories per gram and are your body’s preferred source of energy.
There are two major types of carbs: simple and complex. The difference between them lies in the number of sugar molecules they contain.
Simple carbs — also known as simple sugars — contain one or two sugar molecules, whereas complex carbs have three or more.
A simple sugar may be a mono- or disaccharide.
Monosaccharides are the simplest carbs, in that your body cannot break them down further.
This allows your body to absorb them quickly and easily, with the exception of fructose.
There are three types of monosaccharides (1):
- Glucose: Fruits and vegetables are natural sources of glucose. It’s also commonly found in syrups, candy, honey, sports drinks, and desserts.
- Fructose: The primary natural dietary source of fructose is fruit, which is why fructose is commonly referred to as fruit sugar.
- Galactose: The main dietary source of galactose is lactose, the sugar in milk and milk products, such as cheese, butter, and yogurt.
Disaccharides consist of two sugar molecules — or two monosaccharides — bonded together.
Your body must break the bonded monosaccharides apart before they can be absorbed.
There are three types of disaccharides (1):
- Sucrose (glucose + fructose): Sucrose — most often called table sugar — is a natural sweetener derived from sugarcane or beet. It’s added to foods during processing and occurs naturally in fruits and vegetables.
- Lactose (glucose + galactose): Also known as milk sugar, lactose is found in milk and milk products.
- Maltose (glucose + glucose): Maltose is found in malt beverages, such as beer and malt liquors.
Summary Simple sugars contain one or two sugar molecules. A carbohydrate with one sugar molecule is called a monosaccharide, whereas one with two sugar molecules bonded together is a disaccharide.
To many people, the word “sugar” has a negative connotation.
Many nutrient-dense foods, such as fruits and vegetables, naturally contain sugar and shouldn’t be avoided as they benefit your health.
On the other hand, added sugars — such as in sugary drinks, candy, and desserts — can contribute to many health problems.
Added sugars have been associated with rising levels of obesity, heart disease, and increased cancer risk.
Associated With Obesity
Obesity affects nearly 40% of adults in America (2).
It’s associated with serious health risks including diabetes, heart disease, and cancer.
In addition, obesity is extremely costly to treat. Compared to people of a healthy weight, people who are obese spend thousands of dollars more each year on health care (3).
This imposes a major economic burden on the individual, on families, and taxpayers (4).
Added sugars contribute additional calories to your diet, which can lead to weight gain over time.
May Promote Heart Disease
Heart disease is the leading cause of death in the United States and has been for the past several decades (11).
It’s most often caused by atherosclerosis — a condition in which plaque builds up on the inner walls of blood vessels that lead to your heart, causing them to narrow and harden. This reduces blood flow, which can lead to a heart attack (12, 13).
One study found that people who got 10–25% of their calories from added sugars were 30% more likely to die from heart disease compared to those who got less than 10% of their calories from added sugar (18).
What’s more, that risk nearly doubled for those who got more than 25% of their calories from added sugar.
May Increase Your Risk of Cancer
Excess calories from added sugars can increase inflammation and oxidative stress.
Summary Added sugars have been linked to obesity. What’s more, they may promote heart disease and increase your risk of cancer.
You can find added sugars in different types of foods — even ones you may not think of as sweet, such as ketchup, bread, and canned baked beans.
That said, the main sources of added sugars are sugar-sweetened beverages, candy, desserts, ice cream, and sugary cereals (28).
Look at the nutrition facts panel on a food product to find out how many grams of added sugar it contains.
Historically, food labels didn’t differentiate between natural or added sugar. This made it difficult to determine just how much added sugar you consumed.
By 2020, however, the Food and Drug Administration (FDA) has mandated that manufacturers must list added sugars in grams and as a percentage of the Daily Value (DV) on food labels (29).
Many large food companies have already complied, making it easier to assess the added sugar content of products.
Getting more than these amounts makes it difficult to meet your nutrient needs while staying within your daily calorie limits (31).
Reading the ingredient list on foods can also help you identify added sugars.
Names for added sugars include:
- Anhydrous dextrose
- Brown sugar
- Confectioners powdered sugar
- Corn syrup
- High-fructose corn syrup (HCFS)
- Maple syrup
- Agave nectar
- Raw sugar
Labels list ingredients in descending order of predominance by weight, with the ingredients used in the greatest amount first, followed by those in smaller amounts.
This means that if a product lists sugar as the first ingredient, you know it contains more sugar than anything else.
Summary You can identify added sugars by looking at the food label and reading the ingredient list. Limiting your calories from added sugar can help you meet your nutrient needs while staying within your daily calorie limits.
It’s no question that sugar can be harmful to your health when consumed in excess.
Yet, sugar is only one component of your diet. It's naive to make it solely responsible for obesity and other diseases and conditions in today’s society (32).
Limiting added sugars from sugar-sweetened beverages, sweets, and desserts is important for good health, but never having a piece of cake or a serving of your favorite ice-cream isn’t the right approach. It’s not sustainable, enjoyable or worthwhile for your health.
Besides, simple sugars are found naturally in a wide range of healthy foods, such as fruits, vegetables, and dairy. These foods bring a variety of other important nutrients to your diet, such as vitamins, minerals, antioxidants, and fiber.
Summary Sugar is detrimental to your health when it makes up too much of your diet or you get excess calories from sugar. Therefore, limiting but not completely avoiding sugar — specifically added sugar — is worthwhile for your health.
Simple sugars are carbs with one (monosaccharide) or two (disaccharide) sugar molecules.
Many healthy foods like fruit and vegetables naturally contain sugar and shouldn’t be avoided as they benefit your health. However, excess added sugar is linked to obesity and increased heart disease and cancer risk.
You can find out how much added sugar a product has by looking at the nutrition facts panel or reading the ingredient list.
Despite the harmful effects added sugars can have on your health, you can eat them in moderation and as part of an overall healthy diet.