The main purpose of carbohydrates in the diet is to provide energy. Most carbs get broken down or transformed into glucose, which can be used as energy. Carbs can also be turned into fat (stored energy) for later use. Carbohydrates are one of the three macronutrients- the other two are fats and protein.
Dietary carbohydrates can be split into three main categories:
Sugars: Sweet, short-chain carbohydrates found in foods. Examples are glucose, fructose, galactose and sucrose.
Starches: Long chains of glucose molecules, which eventually get broken down into glucose in the digestive system.
Fibre: Humans cannot digest fibre, although the bacteria in the digestive system can make use of some of them.
Carbohydrates can be divided into refined and complex carbs: complex carbs are unprocessed and contain the fibre found naturally in the food, while simple carbs have been processed and had the natural fibre stripped out.
Complex carbs include vegetables, whole fruit, legumes, potatoes and whole grains.
Simple carbs include sugar-sweetened beverages, fruit juices, pastries, white bread, white pasta, white rice and others
SIMPLE VS COMPLEX
Simple carbs are associated with obesity and type 2 diabetes and cause major spikes in blood sugar levels, which result into a sugar crash, increasing hunger, appetite and more high carb cravings. Simple carbs can also be known as ‘empty calories’.
Complex carbs are loaded with nutrients and fibre, and don't cause the same spikes and dips in blood sugar levels. Studies on high-fibre carbohydrates, including vegetables, fruits, legumes, and whole grains show that eating them is linked to improved metabolic health and a lower risk of disease.