Low carb basics

Much has been written about low-carbohydrate diets, such as Atkins, and there have been some scare stories about the wisdom of eliminating carbs from your diet – especially over the long term.

As with most things, some common sense is called for.  It is important to recognise that there are ‘good’ carbs and ‘bad’ carbs.  As a general rule any processed, packaged and heavily refined food is likely to contain large proportions of ‘bad’ carbs.  White flour (and hence most bread, pasta, cakes, biscuits etc.), sugar (cakes and biscuits again, and sweets of course!), and white rice all fall into this category. Vegetables contain carbohydrates, but most fall into the ‘good’ category.

How can this be?

The key to this is the understanding that the rate at which carbohydrate is converted to glucose in the bloodstream varies from food to food – and that processed, packaged and heavily refined foods are converted most easily. Vegetables are generally ‘good’ carbs as the rate of conversion to glucose is relatively slow.

Why is this important?

Well, the bad carbs boost blood glucose levels quickly and the body gets used to them being there as a source of energy.  This starts a roller coaster ride that leaves a craving for more ‘quick hit’ carbs later in the day.  In the end, more glucose than the body can burn off is in the bloodstream and the surplus glucose is stored as fatty deposits.  If we continue to eat ‘bad’ carbs, putting more quick release glucose into the blood stream each day, the body will never have to turn to the fatty deposits as a source of energy – and we put on weight.

The extent to which we rely on processed, packaged, and refined food has grown tremendously in the last 50 years, at a time when many of us are leading an increasingly sedentary Lifestyle.  It is no coincidence that obesity and diabetes have risen alarmingly over this period.

Between meals do you ever get ‘the shakes’ and reach for that chocolate bar, biscuit or snack?  If so, this is a sure sign that you are, to some extent, on the ‘bad’ carb rollercoaster ride. So how can we use this knowledge and get ourselves off the rollercoaster?

Those little ‘Nutrition Advice’ panels on the side of packaged food give you some guidance on the level of carb the food contains, and even how much of the carb is sugar (the ‘baddest of the bad’).  However, this information does not tell you about the speed of release and, of course, is not readily available for non packaged food.

To really get to the bottom of what is going on, we need to understand a measure sometimes used by nutritionists called the Glycaemic, or Glycemic, Index (GI).  GI gives us a scale of comparison of the rate of release of different foods and there are some moves to have this printed on food packaging to further help consumers make an informed choice.