What are carbohydrates

Carbohydrates are sugars that break down inside the body to create glucose.

Glucose is moved around the body in the blood and is the primary source of energy for the brain, muscles, and other essential cells. 

The healthy body attempts to regulate glucose levels by using a series of hormones – insulin and glucagon, which are produced by the pancreas gland. 

Insulin lowers blood sugar levels by moving the glucose to the various parts of the body and aiding its absorption, excess glucose can be stored in the liver or in fat around the body. 

Glucagon increases blood sugar levels by releasing glucose stored in the liver back into the bloodstream.  Blood sugar levels are usually kept in check if the pancreas and liver are healthy and functioning normally.


There are two types of carbohydrates, simple and complex:

Simple Carbohydrates

Simple carbohydrates refer to sugars with a simple molecular construction of one or two parts. 

Because of their simple molecular structure the body can process these simple sugars quickly – this leads to an energy spike, a sudden rush of energy as sugars are converted to glucose followed by a low once the process is complete and the simple carbohydrates have been used. 

Processed and refined sugars tend to have a high Glycaemic Index (GI) – affecting blood sugar levels quickly - compared to naturally occurring complex carbohydrates which in turn have a lower GI.

Refined sugar is a common source of simple carbohydrates in the modern diet. 

Many processed, packaged and fast foods contain simple carbohydrates as ‘sugar’ is used as a flavour enhancer and can satisfy our palates for sweet food.   Simple carbohydrates from added sugar have little or no nutritional value and are often described as ‘empty calories’.  Most people can benefit from reducing their intake of added sugar (simple carbohydrates).  If you buy processed and packaged foods, choose those with less added sugar, reduce consumption of sugary foods such as cakes, biscuits (cookies), sweets (candy) and regular (not diet) soft drinks.

Simple carbohydrates are not always bad and also exist naturally in foods that do provide nutritional benefits, notably fruits, milk and other dairy products.  Most fruits contain good levels of fibre, vitamins and micro minerals as well as antioxidants.  Milk and dairy products are good sources of protein and calcium, most people agree that both fruit and dairy products are important to a well-balanced healthy diet.


Complex carbohydrates refer to sugars with a complex molecular structure of three or more parts; due to the complex structure of these molecules it takes the body longer to break them down to produce the glucose it needs for energy.  Foods rich in complex carbohydrates also contain valuable vitamins, minerals and fibre which are vital to overall health and wellbeing.

As foods containing complex carbohydrates are processed more slowly by the body they can provide sustained energy levels over longer periods of time than simple carbohydrates.  The Glycaemic Index (GI) of foods rich in complex carbohydrates is therefore lower.

Glycaemic Index (GI)

The glycaemic index of food is a measure of how quickly glucose levels rise in the blood after eating.  Foods with higher GI levels tend to contain more simple carbohydrates whereas foods containing complex carbohydrates will tend to produce a lower GI score as it takes the body longer to break these down into glucose. 

Generally foods with a lower GI, which release glucose more slowly, are considered healthier – because the body has to work harder to break these foods down you feel fuller for longer and burn more calories digesting and recovering glucose. However, some foods with lower GI scores are also high in fat and salt which may make them less healthy.

What if I Eat Too Many Carbohydrates?

Eating too many carbohydrates will lead to weight gain, this is because the body will store unused glucose for later use. 

Tired Feeling

Simple carbohydrates, such as those found in candy, cookies, crackers, some fruits and vegetables, soft drinks, energy drinks and fruit drinks, cause rapid spikes in your blood sugar levels. A rapid spike in blood sugar often results in an energy crash within an hour or two, warns Sharon Richter, a certified dietetic nutritionist in New York City. If you eat simple carbohydrates, pair them with a food high in protein or fiber, Richter continues. Protein and fiber slow the digestion of the carbohydrates and limit the spike in your blood sugar levels.


Diets containing large amounts of carbohydrates are associated with obesity and increased caloric intake. In the February 2004 issue of “Morbidity and Mortality Weekly Report” from the Centers of Disease Control and Prevention, a survey found that between the years 1971 and 2000 the daily intake of calories increased by around 22 percent for women and around 7 percent for men. Carbohydrate intake is the main cause of this increase. The consumption of food away from home, salty snacks, soft drinks and pizza contribute to this increase in carbohydrate calories.

Gastrointestinal Distress

Carbohydrate intake may increase the amount of gastrointestinal distress you experience. The National Digestive Diseases Information Clearinghouse reports that the digestion of carbohydrates causes gas more than any other type of food, including fat. As gas builds up in the digestive tract, you may experience abdominal discomfort, belching, bloating and flatulence.

Triglyceride Levels

Added sugars, including sugars and syrups added during food processing and those you add to food before consumption, may increase cholesterol levels. The August 2009 issue of “Circulation,” a journal published by the American Heart Association, reports that high triglyceride levels often result from diets high in fructose, glucose and sucrose. Triglycerides are a form of cholesterol that attributes to plaque buildup in your arteries, which is associated with an increased risk of heart attack and stroke.