Unlike most diets, the low glycemic diet isn’t a fad. It was developed at the University of Sydney to help diabetics have better blood sugar control. In the low glycemic diet (also known as the glycemic index diet or GI diet), all foods containing carbohydrates are assigned a rating – the glycemic index (GI). It’s not a measurement as such, it is just a comparison to glucose, which has a rating of 100.
What’s wrong with high GI?
Foods with a high GI digest more quickly than those with low GI. This means that they cause rapid rise in blood sugar, followed by an insulin response. The insulin “grabs” the sugar out of the blood, because high blood sugar is harmful to the body. It then stores the sugar for energy in the muscles and liver, or as fat if no energy storage is required. The rapid drop in blood sugar which follows often gives rise to sugar craving and the whole process starts again.
Why a low glycemic diet is beneficial
If you eat foods with a low GI, they will digest more slowly. Sugar will be released at a steady rate into the blood stream, avoiding blood sugar highs. In turn, this avoids fat storage and subsequent sugar craving. This has the obvious benefit of helping with weight control, but that’s not the only benefit. Eating foods which cause high blood sugar can damage long term health and increase the risk of illnesses such as heart disease and type 2 diabetes.
How to have a low glycemic diet
Planning a low GI diet isn’t as straightforward as planning a low calorie diet. For a start, nutrition panels on food packaging don’t show GI. There are plenty of books and online resources which give GI tables, but these aren’t always consistent with each other (see below for links to some reliable resources).
However, there are a few basics that everyone agrees on.
- Wholegrains are lower GI than white carbohydrate foods.
- Vegetables are generally low GI, but potatoes are fairly high.
- Fibre reduces GI, so many fruits have a low to medium rating despite their high sugar content.
- Fruit juice on the other hand doesn’t have much fibre so will be higher GI.
- What you eat with carbs can modify their GI. Fibre, protein and fat all slow down carbohydrate digestion.
As a simple guide, here are 10 ideas for a low glycemic diet:
- Use sweet potato for baking, mashing, chips etc. instead of white potato
- Chose wholemeal or 50/50 bread
- Choose wholemeal rice and pasta, or cook a mixture of wholemeal and white
- Add beans or vegetables to meals to increase fibre content
- Avoid high sugar breakfast cereals and choose high fibre ones like muesli, porridge, Weetabix
- Instead of sugary snacks, snack on fresh or dried fruit, nuts, seeds or dark chocolate
- Eat protein at each meal
- Drink smoothies instead of juice (because they are made from the whole fruit)
- If you snack on biscuits, choose ones made with wholegrains (like digestives and oat biscuits)
- Try to eat fruit as fresh as possible, because more starch turns to sugar as it ripens, increasing the GI.