Starch vs. Glycogen: What's the Difference?
Edited by Aimie Carlson || By Harlon Moss || Published on July 3, 2026
Starch is a carbohydrate found in plants for energy storage, whereas glycogen is a carbohydrate stored in animals and fungi for energy.
Key Differences
Starch and glycogen are both polysaccharides, but they differ in their structure and function. Starch is the primary form of carbohydrate storage in plants and is found in foods like potatoes, rice, and wheat. It consists of two types of molecules: amylose and amylopectin, with amylose being linear and amylopectin being branched. Glycogen, on the other hand, is the main form of carbohydrate storage in animals and fungi. It is highly branched and more compact than starch, making it readily available for quick energy release when needed by the body.
The structure of starch and glycogen significantly influences their respective functions. Starch, with its mixture of linear and branched molecules, is designed for long-term energy storage in plants. It is broken down more slowly, providing a sustained energy source. Glycogen’s highly branched structure allows for rapid release of glucose when energy is needed quickly, such as during intense physical activity.
In terms of digestion and dietary significance, starch is a major part of the human diet, providing a significant source of energy. When consumed, it is broken down into glucose, which is used by the body for energy. Glycogen, meanwhile, does not play a direct role in the human diet as it is not a significant component of foods. Instead, it is synthesized and stored in the liver and muscles of the human body and utilized as an internal energy reserve.
Starch can be divided into two types based on its solubility and digestibility: rapidly digestible starch and slowly digestible starch. This division is crucial for dietary considerations, as different types of starch have different impacts on blood sugar levels. Glycogen’s structure, being more uniform, does not have such divisions but is crucial for regulating blood sugar levels by providing glucose when needed.
The presence of these carbohydrates in different organisms highlights their roles. Starch is abundant in plant cells, particularly in seeds and tubers, where it serves as an energy reserve for germination and growth. Glycogen is found primarily in animal cells, especially in the liver and muscle tissue, where it provides an immediate energy source for metabolic needs.
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Comparison Chart
Found In
Plants
Animals and fungi
Structure
Mix of linear (amylose) and branched (amylopectin) molecules
Highly branched molecules
Function
Long-term energy storage in plants
Quick energy release in animals and fungi
Digestibility
Broken down into glucose for energy
Utilized internally for energy
Dietary Role
Major part of human diet
Not directly consumed in diet
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Starch and Glycogen Definitions
Starch
Carbohydrate storage in plants.
Potatoes are high in starch.
Glycogen
Provides quick energy release.
Glycogen is used during intense exercise.
Starch
Composed of amylose and amylopectin.
Starch's structure affects its digestibility.
Glycogen
Highly branched structure.
The branching of glycogen facilitates rapid glucose release.
Starch
Used as a thickener in cooking.
I used starch to thicken the gravy.
Glycogen
Not a direct part of the human diet.
Glycogen comes from internal synthesis, not diet.
Starch
Energy source in human diet.
Starch provides sustained energy.
Glycogen
Carbohydrate storage in animals and fungi.
Glycogen is stored in the liver and muscles.
Starch
Turns blue-black with iodine.
The iodine test confirmed the presence of starch in the sample.
Glycogen
Synthesized from glucose.
The body converts excess glucose into glycogen.
Starch
A naturally abundant nutrient carbohydrate, (C6H10O5)n, found chiefly in the seeds, fruits, tubers, roots, and stem pith of plants, notably in corn, potatoes, wheat, and rice, and varying widely in appearance according to source but commonly prepared as a white amorphous tasteless powder.
Glycogen
A polysaccharide, (C6H10O5)n, that is the main form of carbohydrate storage in animals and is found primarily in the liver and muscle tissue. It is readily converted to glucose as needed by the body to satisfy its energy needs. Also called animal starch.
Glycogen
(carbohydrate) A polysaccharide that is the main form of carbohydrate storage in animals; converted to glucose as needed.
Glycogen
A white, amorphous, tasteless substance resembling starch, soluble in water to an opalescent fluid. It is found abundantly in the liver of most animals, and in small quantity in other organs and tissues, particularly in the embryo. It is quickly changed into sugar when boiled with dilute sulphuric or hydrochloric acid, and also by the action of amylolytic ferments.
Glycogen
One form in which body fuel is stored; stored primarily in the liver and broken down into glucose when needed by the body
FAQs
What is starch?
Starch is a carbohydrate found in plants used for energy storage.
Where is glycogen stored in the body?
Glycogen is stored in the liver and muscle tissues.
Is glycogen a significant part of the human diet?
No, glycogen is synthesized in the body and not a direct part of the diet.
How does starch affect blood sugar?
Starch breakdown into glucose can impact blood sugar levels.
Is starch found in animal products?
No, starch is primarily found in plant-based foods.
Do plants store glycogen?
No, plants store energy as starch, not glycogen.
What are the two types of starch?
The two types are amylose (linear) and amylopectin (branched).
Can humans digest starch?
Yes, humans digest starch into glucose for energy.
Are all starches easily digestible?
No, digestibility varies based on the type of starch.
What foods are high in starch?
Foods like potatoes, rice, and bread are high in starch.
Can glycogen levels affect athletic performance?
Yes, adequate glycogen stores are important for sustained physical activity.
How is glycogen used by the body?
Glycogen is used for quick energy release, especially during physical activity.
Can glycogen be used as a dietary supplement?
No, glycogen supplements are not common as it's produced internally.
Does the body store excess glucose as glycogen?
Yes, excess glucose can be converted to glycogen for storage.
What is the primary function of glycogen in animals?
It serves as an internal energy reserve.
How quickly is glycogen used during exercise?
Glycogen is quickly broken down for energy during intense exercise.
How does the body make glycogen?
Glycogen is synthesized from glucose in the body.
Can starch be used in non-food products?
Yes, starch is used in products like biodegradable plastics and adhesives.
Is starch easily converted to sugar in the body?
Yes, the body converts starch into glucose, a form of sugar.
What role does starch play in cooking?
Starch is often used as a thickening agent in cooking.
About Author
Written by
Harlon MossHarlon is a seasoned quality moderator and accomplished content writer for Difference Wiki. An alumnus of the prestigious University of California, he earned his degree in Computer Science. Leveraging his academic background, Harlon brings a meticulous and informed perspective to his work, ensuring content accuracy and excellence.
Edited by
Aimie CarlsonAimie Carlson, holding a master's degree in English literature, is a fervent English language enthusiast. She lends her writing talents to Difference Wiki, a prominent website that specializes in comparisons, offering readers insightful analyses that both captivate and inform.
