GI and weight loss

Why is GI so important for weight loss?

Low GI breakfast cereal You will more than likely have heard the term Glycemic Index or GI, but may not have a clear understanding about what it is.

 Quite simply, GI is a measure of the response that carbohydrates have on our blood sugar levels, which in turn affects our levels of fat storage.

 So, if there’s one thing you should know it’s this:

Low GI food = Low fat stores ↓

High GI food = High fat stores ↑

The GI scalePersonal Trainer Macclesfield: GI scale

Ok, so it doesn’t take a scientist then to know that a diet based on lower GI foods is the one to go with if you want to get lean and look amazing.

 The good thing about taking this approach to your nutrition is that it’s sustainable, has great results, and doesn’t involve a complex approach. You really just need to know which foods are low on the GI scale and which foods are high.

 The GI scale runs from 0 to 100 and foods are categorised as per the chart on the right.

 Obviously the aim is to eat as many foods with a GI of 55 or less, and fewer foods above 55. However, the 80/20 rule should always apply as the most important thing is that you find something that is sustainable and allows you to live a life of moderation.

Where to start

 The truth is that small steps make big differences. Simply by reducing your intake of potatoes or replacing white bread for wholegrain bread, bananas for apples, and so on, all helps you lose the pounds and, more importantly, keep them off!

 There are plenty of good books on the market to help you with implementing and sustaining a low GI eating approach. These are the books I always recommend:

  • The Food Doctor Everyday Diet (Ian Marber): If you buy one nutrition book it should be this… I recommend this to all my clients as it spells out 10 clear principles that are the foundations of maintaining a healthy weight. It’s easy to follow and includes some good recipes to help you get started.
  • The Low GL Diet Bible (Patrick Holford): As the strap line says this book is “The perfect way to lose weight, gain energy and improve your health: The Healthy Way to Lose Fat Fast, Gain Energy and Feel Superb”. If you’re the kind of person that really likes to get down in the detail and understand exactly why a low GL diet is good for weight loss and health then this is the book for you. If you prefer a simpler read then the Food Doctor book above is your better option.

 In the meantime, to help you get started, below is a short list of replacements for High GI foods that will kick-start your inch loss:

High GI Foods Lower GI alternative
White French Baguette Sliced wholegrain bread
Chips from potatoes Chips from celeriac
Baked potato Boiled new potatoes
White rice Brown rice or quinoa (keen-wah)
White pasta Wholewheat or spelt pasta
Crisps Unsalted mixed nuts
Traditional cereals e.g Frosties Lizi’s Granola or porridge
Chocolate bar / biscuits Pear, mixed seeds and yogurt
Chinese takeaway Home made chicken, broccoli and cashew stirfry, with small amount of buckwheat noodles
Pizza Melted brie with Parma ham and mushrooms on fresh oatcakes
Parsnips Broccoli


 The Glycemic Index web site contains a useful database of the GI measure of different foods. Notice that the way the same ingredient is cooked can have a bearing on the GI level!