Ask the experts… what is the difference between simple and complex carbohydrates?

sweet potatoQ What is the difference between simple and complex carbohydrates? 

This is one of the most common questions I’m asked in my clinic. Over the years carbohydrates have developed a negative image and so people tend to assume they are all the same.

However, carbohydrates are one of three necessary macro-nutrients that provide calories in our diets. The other two are protein and fat. Carbohydrates provide most of the energy needed in our daily lives, both for normal body functions (such as heartbeat, breathing, digestion and brain activity) and for exercise (like cycling, walking, running up the stairs and all types of resistance training). A good supply of complex carbohydrates is absolutely necessary to sustain good energy levels.

Carbohydrates are considered simple or complex based upon their chemical structure. The main difference between simple and complex carbs is that simple carbohydrates are broken down and digested very quickly because they contain refined sugars and less essential vitamins and minerals. Examples include table sugar, fruit juice, molasses, maple syrup and brown sugar.

Complex carbs take longer to digest and are full of fibre, vitamins and minerals. Examples include vegetables (sweet potatoes, pumpkin), whole grain breads, oatmeal, lentils, brown rice and wholegrain wheat pasta.

Ideally, your diet should be based around mostly complex carbohydrates. The best way to determine if the product you are buying is a whole grain product is to look at the ingredients list. The ingredients will be listed in descending order by weight, and the first one should contain the phrase ‘whole wheat’ or ‘whole grain’.

maria bezAbout our expert: Nutritionist Maria Bez is a registered nutritionist with the British Association of Nutritional Therapists. She has a BSC degree in Nutritional Medicine and practices from Nourish, her clinic in Bath. As well as attending to clients, she writes and speaks on all matters relating to nutrition and lifestyle. She is dedicated to providing individuals with information and advice to take control of their own health and well-being.

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