What are simple carbohydrates called? An exploration of sugars

November 13, 2025 •

3 min read

According to the Cleveland Clinic, simple carbohydrates are also called sugars. This guide explains what are simple carbohydrates called, including the specific names for their single-unit and two-unit forms and how their quick digestion affects the body.

Quick Summary

Simple carbohydrates are known as sugars and are categorized chemically as monosaccharides and disaccharides. They consist of one or two sugar molecules, are quickly digested, and provide a fast source of energy, impacting blood sugar levels rapidly.

Key Points

Scientific Classification: Simple carbohydrates are chemically known as monosaccharides (single sugars) and disaccharides (double sugars).
Common Terminology: Most commonly, simple carbs are referred to as "sugars" in everyday dietary and health discussions.
Rapid Digestion: Due to their simple structure, these carbohydrates are digested and absorbed quickly by the body, providing a rapid energy boost.
Blood Sugar Impact: This rapid digestion can lead to quick spikes and crashes in blood sugar levels.
Nutrient Sources: Simple carbs are found in both natural foods like fruits and milk, and processed items such as candy and soda.
Nutrient Density: Many foods high in simple carbohydrates, especially processed ones, offer little nutritional value beyond calories and are often called "empty calories".

The Scientific Names: Monosaccharides and Disaccharides

Simple carbohydrates are a fundamental macronutrient group that the body breaks down and absorbs quickly for energy. Chemically, they are divided into two main categories based on the number of sugar units: monosaccharides and disaccharides.

Monosaccharides (Single Sugars)

Monosaccharides are single sugar molecules and are the simplest units of carbohydrates. They are absorbed directly into the bloodstream without further digestion.

Common examples include:

Glucose: The body's primary energy source, often called "blood sugar".
Fructose: Found in fruits and honey, known as "fruit sugar".
Galactose: A component of lactose in milk.

Disaccharides (Double Sugars)

Disaccharides are formed by two monosaccharides bonded together. They must be broken down during digestion before absorption.

Notable examples are:

Sucrose: Table sugar, a combination of glucose and fructose.
Lactose: Milk sugar, made of glucose and galactose.
Maltose: Malt sugar, consisting of two glucose molecules, found in some grains and malt beverages.

Quick Digestion and Energy

Simple carbohydrates are quickly broken down into glucose and absorbed into the bloodstream, providing a rapid energy boost. This can cause a quick rise and fall in blood sugar levels, sometimes leading to energy crashes. Complex carbohydrates, with many sugar units, digest slower for sustained energy release.

Comparison: Simple vs. Complex Carbohydrates


Feature	Simple Carbohydrates	Complex Carbohydrates
Structure	One or two sugar molecules (monosaccharides, disaccharides).	Long chains of sugar molecules (polysaccharides).
Digestion	Rapidly digested and absorbed by the body.	Digested slowly, taking more time to break down.
Energy Release	Provides a quick, short-lived burst of energy.	Offers a more sustained, longer-lasting energy source.
Blood Sugar Impact	Can cause rapid spikes and subsequent crashes in blood sugar.	Leads to a more gradual, stable rise in blood sugar.
Nutrient Density	Often, but not always, low in nutrients; refined sugars offer "empty calories".	Generally high in fiber, vitamins, and minerals.
Food Sources	Fruits, milk, candy, sodas, table sugar.	Whole grains, vegetables, legumes, brown rice.

Common Simple Carbohydrate Food Sources

Simple carbohydrates are in various foods. The nutritional value depends on the source; some provide essential nutrients, while others are mainly "empty calories".

Natural sources:

Fruits and Fruit Juices: Contain fructose and glucose. Whole fruits are better due to fiber.
Milk and Dairy Products: Contain lactose.
Honey: Contains fructose and glucose.

Processed sources:

Sodas, Candies, and Sugary Snacks: Often have high amounts of refined and added sugars with minimal nutritional benefits.
Table Sugar: Sucrose, commonly added to foods and drinks.

Conclusion: Choosing Your Carbs Wisely

Understanding what simple carbohydrates are called and their sources is crucial for managing energy, weight, and health. The impact varies depending on whether they come from nutrient-rich foods like fruits or processed items with added sugars. Prioritizing complex carbohydrates and natural simple sugars in moderation supports stable energy and balanced nutrition. For more information on healthy carbohydrate intake, the Centers for Disease Control and Prevention is a reliable resource. More information on healthy eating can be found on the CDC website.

Choosing Carbohydrates for Your Health

Making informed dietary choices requires understanding different simple carbohydrates and their sources. While all carbohydrates become glucose for fuel, other nutrients like fiber affect absorption and health impact. Prioritizing whole-food simple carbohydrates and limiting processed sugary snacks is a simple strategy for a healthier diet.

A Quick Guide to Simple Sugars

Monosaccharides: Single sugar molecules like glucose, fructose, and galactose.
Disaccharides: Two monosaccharide units combined, such as sucrose, lactose, and maltose.
Natural vs. Added: Found naturally in fruits and milk, but also added to many processed foods.
Digestion Speed: Digested quickly due to fewer chemical bonds.
Energy and Health: Provide fast energy but can cause blood sugar spikes, which are linked to health issues over time.

Understanding the 'Saccharide' Family

The term 'saccharide' comes from the Greek word for sugar. Simple carbohydrates (monosaccharides and disaccharides) are smaller, sweeter, and faster-digesting members. Understanding them alongside larger polysaccharides like starch is essential for nutritional science.

Frequently Asked Questions

In everyday language and general health discussions, simple carbohydrates are most often referred to as "sugars".

A monosaccharide is a single sugar unit and is the simplest form of a carbohydrate, while a disaccharide is composed of two monosaccharides bonded together.

No. While added sugars in processed foods can be unhealthy due to a lack of other nutrients, naturally occurring simple carbohydrates in foods like fruits and milk are part of a balanced diet and provide beneficial vitamins and minerals.

Because of their simple chemical structure, the body can break them down and absorb them very quickly, leading to a rapid release of glucose into the bloodstream for energy.

Glucose is often called "blood sugar" because it is the main type of sugar that circulates in the bloodstream to fuel the body's cells.

The suffix "-ose" is a convention used in chemical nomenclature to denote a sugar.

The difference is often tied to the food's nutrient density. Healthy sources like whole fruits contain natural simple sugars along with fiber, vitamins, and minerals. Unhealthy sources like soda and candy contain added sugars and provide little nutritional benefit, often referred to as 'empty calories'.