Macronutrients: carbohydrates

Macronutrients: Carbohydrates

Definition and Classification

  • Carbohydrates are organic compounds consisting of carbon, hydrogen, and oxygen atoms.
  • They are divided into simple carbohydrates (sugars) and complex carbohydrates (starches and fibres).


  • Carbohydrates are the body’s main source of energy.
  • They help fuel your brain, kidneys, heart muscles, and central nervous system.
  • Fiber, a type of complex carbohydrate, aids in digestion and helps maintain a healthy weight.

Dietary Sources

  • Examples of simple carbohydrates include fruits, milk, and milk products.
  • Complex carbohydrates can be found in whole grain breads, cereals, starchy vegetables, and legumes.

Digestion and Absorption

  • Digestion of carbohydrates begins in the mouth with the enzyme salivary amylase.
  • Most of the final digestion takes place in the small intestines with the help of pancreatic amylase.
  • Simple carbohydrates are easily and quickly absorbed and provide a quick energy boost.

Health implications

  • Overconsumption may lead to weight gain, and increase the risk for diabetes and heart disease.
  • Underconsumption could lead to lack of energy and nutrient deficiencies.
  • Generally, between 45% to 65% of your calorie intake should come from carbohydrates. This equates to around 225 to 325 grammes per day for a 2000-calorie diet.


  • The quality and nutritional value of carbohydrates can be preserved by storing the carbohydrate-rich foods at the correct temperature, and by cooking and processing them appropriately.

Remember not to confuse carbohydrates with carbon hydrates, which would be incorrect.