What Name is Fructose Also Known As?

January 11, 2026 •

3 min read

With the chemical formula C₆H₁₂O₆, fructose is a simple sugar, or monosaccharide, that exists as a white crystalline solid when pure. It is most commonly found in nature in fruits, honey, and some root vegetables. So, what name is fructose also known as? It is widely recognized by the common name 'fruit sugar'.

Quick Summary

Fructose is also known as fruit sugar due to its natural occurrence in many fruits, vegetables, and honey. An older name for it is levulose, derived from its ability to rotate polarized light to the left.

Key Points

Fruit Sugar: Fructose is most commonly known as 'fruit sugar' due to its prevalence in fruits, as well as honey and some vegetables.
Levulose: Another name for fructose is 'levulose,' an older term referencing its ability to rotate polarized light to the left.
Metabolic Pathway: Unlike glucose, fructose is primarily metabolized in the liver and does not require insulin for initial processing, which leads to a lower impact on immediate blood glucose levels.
High-Fructose Corn Syrup: Fructose is a major component of high-fructose corn syrup (HFCS), a manufactured sweetener added to many processed foods and drinks.
Source Matters: The health effects of fructose are influenced by its source; naturally occurring fructose in fruits is not associated with the same negative outcomes as excessive intake from added sugars.
Excessive Intake Concerns: High consumption of added fructose has been linked to metabolic issues, such as insulin resistance and fatty liver disease, due to how the liver processes it.

Fructose: A Common Monosaccharide with Many Names

Fructose, a simple sugar, plays a significant role in both nature and the food industry. While its chemical name is d-arabino-hex-2-ulose, most people recognize it by its common aliases. Understanding these different names, along with the sugar's properties and sources, can provide clarity on what is often a misunderstood carbohydrate.

The Most Common Alias: Fruit Sugar

One of the most straightforward and widely used alternative names for fructose is 'fruit sugar'. This moniker is highly intuitive, as fructose is the primary sugar found in most fruits. From a ripe apple to a bunch of grapes, the sweetness you taste is largely attributed to fructose content. This naturally occurring sugar is also abundant in honey, where bees break down sucrose from nectar into glucose and fructose. The concentration of fructose varies significantly between different fruits and natural sweeteners, affecting their overall sweetness profile.

The Historical and Scientific Name: Levulose

Before 'fructose' became the standard term, this sugar was often referred to as 'levulose'. This name has a scientific origin, stemming from the word 'laevorotatory,' which describes a substance's ability to rotate the plane of polarized light to the left. Early chemists observed this property in fructose, leading to the designation 'levulose,' contrasting it with glucose (also known as dextrose), which rotates light to the right. While less common in everyday conversation today, the term 'levulose' is still relevant in scientific and historical contexts.

How Fructose is Used in Food Production

Fructose is a popular sweetener in the commercial food industry, often as part of high-fructose corn syrup (HFCS). HFCS is produced by converting the glucose in cornstarch into fructose using enzymes. It comes in various formulations, such as HFCS-42 and HFCS-55, which indicate the percentage of fructose present. Because fructose is the sweetest naturally occurring carbohydrate, it is prized for enhancing the taste of many processed foods and beverages.

Natural vs. Added Fructose

It is important to distinguish between naturally occurring fructose found in whole foods and added fructose used in processed products.

Natural Fructose: This is the sugar found within fruits and vegetables, accompanied by fiber, water, and essential nutrients. The fiber slows down digestion and absorption, mitigating rapid blood sugar spikes.
Added Fructose: This comes from sweeteners like high-fructose corn syrup and pure crystalline fructose. These are separated from their natural sources and added to processed foods, sodas, and candies. This type of fructose is absorbed more rapidly and can have different metabolic effects when consumed in large quantities.

The Metabolic Difference: Fructose vs. Glucose

While both glucose and fructose are monosaccharides with the same chemical formula ($$C6H{12}O_6$$), they are metabolized differently by the body. This is a key difference that impacts their effect on health.


Feature	Fructose	Glucose
Primary Metabolic Location	Liver	Cells throughout the body
Insulin Requirement	No insulin required for metabolism	Insulin is required for uptake by cells
Blood Sugar Impact	Low impact; does not raise blood sugar rapidly	Significant impact; triggers insulin release
Energy Storage	Converted to glucose or stored as fat in the liver	Metabolized for immediate energy or stored as glycogen
Sweetness	The sweetest naturally occurring sugar	Less sweet than fructose and sucrose

Health Considerations with High Fructose Intake

Excessive intake of added fructose, often from high-fructose corn syrup, has been linked to potential health concerns. When the liver is overwhelmed by high fructose consumption, it can increase the production of fat (a process called de novo lipogenesis), leading to elevated triglycerides and a greater risk for non-alcoholic fatty liver disease (NAFLD). Moderating intake, especially from processed sources, is recommended by health experts. However, the fructose found naturally in fruits is not typically a concern because it is consumed alongside beneficial fiber and nutrients.

Conclusion: More Than Just a Sugar

Fructose, the sugar also known as 'fruit sugar' and 'levulose', is a naturally occurring monosaccharide with unique metabolic pathways. While present in whole foods, it is also widely used as an additive in processed foods and beverages. Understanding these various names and its distinct characteristics is key to making informed dietary choices. By prioritizing fructose from natural, whole-food sources and limiting consumption of processed, high-fructose products, individuals can maintain a healthier balance in their diet.

Center for Science in the Public Interest: Fructose Overview

Frequently Asked Questions

The most common name for fructose is 'fruit sugar,' as it is found naturally in many fruits, vegetables, and honey.

Fructose was called levulose because it is a 'laevorotatory' compound, meaning it rotates the plane of polarized light to the left.

No, fructose is a monosaccharide (single sugar), while table sugar is sucrose, a disaccharide made of one glucose molecule and one fructose molecule bonded together.

Fructose occurs naturally in fruits, honey, and vegetables, but is also commercially produced from sucrose or cornstarch to be used as an added sweetener, like in high-fructose corn syrup.

Fructose has a lower impact on immediate blood glucose levels compared to glucose because it is metabolized differently by the liver and does not require insulin for uptake.

Consuming fructose from whole fruits is not considered unhealthy. The fiber in whole fruits slows down sugar absorption, and fruits provide other beneficial nutrients.

Excessive intake of added fructose, particularly from processed foods and sugary drinks, has been linked to potential health issues such as insulin resistance, obesity, and non-alcoholic fatty liver disease (NAFLD).

Fructose can be either, depending on its source. It is considered a natural sugar when consumed from whole foods and an added sugar when incorporated into processed products.