Difference Between Carbohydrates and Fats

The key difference between carbohydrates and fats is that carbohydrates are soluble in water while most fats are not soluble in water.

Food and affiliated sciences are riddled with claims of reducing weight, gaining weight and toning the body. Terms like carbohydrates, fats, proteins, and vitamins are specific terms with scientific value. Carbohydrates and fats are two such terms that refer to two macromolecules essential for our body.


1. Overview and Key Difference
2. What are Carbohydrates
3. What are Fats
4. Similarities Between Carbohydrates and Fats
5. Side by Side Comparison – Carbohydrates and Fats in Tabular Form
6. Summary

What are Carbohydrates?

Carbohydrates, also known as saccharides, are organic compounds made up of carbon, hydrogen, and oxygen. According to the number of building blocks (monomers) in a carbohydrate, they can be monosaccharides, disaccharides, oligosaccharides or polysaccharides.

Figure 01: Carbohydrates

Carbohydrate monomers are the monosaccharides (simple sugars). In fact, they are the simplest of all and contribute to the formation of other types. Monosaccharides include glucose and fructose. Furthermore, simple sugars serve as an energy source and a base product for synthesis. Glucose exists as glycogen in our body. In plants, glucose exists as starch. Moreover, most starchy plant-based foods are high in carbs and provide 4 kilocalories per gram of carbohydrate. Oligosaccharides are helpful in maintaining gut bacteria, which helps in the synthesis of various products.

What are Fats?

Fats are organic compounds made up of carbon, hydrogen, and oxygen. The term fats includes all lipids and oils, as well as, cholesterol esters. There are two types of fats; saturated and unsaturated. Unsaturated fats contain fatty acids chains which have double bonds between C atoms. They convert into other molecules easily with the insertion of a branching molecule. Saturated fats do not have double bonds between the C atoms of their fatty acid chains.

Figure 02: Fats

Fats are important in energy production, storing of energy, preventing heat dissipation, absorption of nutrients like vitamins, etc. Fats produce 9 kilocalories per gram. They tend to synthesize other products when transported to the liver. All of them are important, but in some instances, the excess of these metabolites can lead to death.

What are the Similarities Between Carbohydrates and Fats?

  • Carbohydrates and fats are organic molecules.
  • They are macromolecules composed of monomers.
  • Both of them contain C, H and O atoms.
  • They are energy sources.
  • Both include into our diet.
  • Excess of both types can lead to disease conditions.

What is the Difference Between Carbohydrates and Fats?

Carbohydrates vs Fats

Carbohydrates are the most abundant dietary source of energy of all living organisms. Fats are a chief store of energy.
Soluble in water Non-soluble in water
Monosaccharides, disaccharides, oligosaccharides, and polysaccharides. Saturated and unsaturated fats.
Made up of glucose and fructose Composed of fatty acids and glycerol
Hydrophilic Hydrophobic
Energy Source
First choice of energy sources Less desirable source of energy
Store mostly in the liver and muscles Stored mostly in the liver and other peripheral tissues.
Energy Release per Gram
Produce 4 kilocal per gram Produce 9 kilocal per gram

Summary – Carbohydrates vs Fats

Carbohydrates and fats are macromolecules containing C, H, and O atoms. They provide energy. Furthermore, carbohydrates are water soluble and serve as the main energy source for all living organisms. In contrast, fats are non-soluble in water and are less desirable as an energy source. But they are good energy stores. Carbs produce comparatively less energy per gram. This is the difference between carbohydrates and fats.


1. Davidson, Eugene A. “Carbohydrate.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 14 Mar. 2018, Available here.
2. Nordqvist, Christian. “Types of Fat: The Good and the Bad.” Medical News Today, MediLexicon International, 22 June 2017, Available here.

Image Courtesy:

1. “587597” (CC0) by Pixabay
2. “Avoiding Trans Fat” By The U.S. Food and Drug Administration – (Public Domain) via Commons Wikimedia