Defining Carbohydrates, Fats and Protein

Author: FITivate | Published date: November 21, 2023 | Category: Nutrition
carbohydrate, protein, fats, Macros, Macro nutritent

We do often see these words frequently, but many of us might not understand how they are processed by our bodies. Here, we will explore more about these nutritional elements and their importance to the bodily functions.


Carbohydrates are broken down by the body into glucose, absorbed into the blood stream to be burned for energy.

Considered to be primary source of energy, ahead of fats and protein and broadly categorised into 2 main groups :

  • Simple Carbohydrates : Quickest to be broken down and easily enter the blood stream as glucose. Found in honey, fruits, table sugar and those sweet tasting desserts
  • Complex Carbohydrates : Due to the complex molecular structure, they take a relatively longer time to be broken down. Gradually introduced into the blood stream for energy generation over a longer period of time. Typically found in starchy and fibrous food stuff such as whole grains, vegetables, nuts.

The blood stream can only hold a limited amount of blood glucose, the excess will be stored up by the liver and muscles in the form of glycogen as reserves. The glucose that overflows out from these reserves will be then stored as fats.

A sedentary person who consumes too much simple carbs will face overweight issues, since much of these unused glucose will be rapidly stored up as fats.


Fats are made up of fatty acids and glycerol which serve as a secondary source of energy.

  • Transporting fat soluble vitamins (A, D, E, K) around the system,
  • Make up part of the cell membrane
  • Act as shock absorbers for the organs.

Broadly catagorised in 3 groups :

  • Unsaturated Fats : Consist of monosaturated and polysaturated fats which helps in the formation and transportation of HDL – High Density Lipoprotein (good cholesterol) throughout the body.  Helps to prevent Cardiovascular diseases. Typically found in foods such as olive oil, salmon and nuts.
  • Saturated Fats : Even though not as bad as trans-fats, but can still raise over all cholesterol levels in the body and should be consumed in moderation. Typically found in dairy, butter, red meat.
  • Trans-fats :  Considered to be the most harmful and should be entirely avoided. These are ones that are proven to raise the LDL (bad cholesterol) in the body which can lead to cardiovascular complications. Typically found in hydrogenated vegetable oil and margarine.


Basic building blocks for the muscle, it helps the muscle cells grow, recover, repair and absorb nutrients.

There are 21 different amino acids that make up protein and are categorized into 3 groups, namely: essential, conditionally-essential, and non essential.

Protein found in food can be identified as complete and incomplete. Food containing complete proteins mean that they have the entire array of amino acids present (eg, Whey protein, milk, eggs, chicken, beef etc). Incomplete protein foods lack of one or some amino acids out of the 21 (eg, Vegetables, fruits, rice, bread).

By : Alvin Ho

B (Eng), MBA, Certified Allied Healthcare/Fitness Professional (EIMS), Master Fitness Trainer / Fitness Nutrition, Resistance & Endurance Training Specialist (NFPT)



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