Secrets of the GI Diet

The Glycemic Impact Diet

By eDiets Nutrition Team

GI is a hot topic in the world of nutrition. But, what is GI all about? Great ideas? Good intentions? In this case, GI stands for Glycemic Impact. While most of us will have heard of, and might even have tried, low carb plans, low GI is another way to control carbohydrate intake while still including carbohydrate foods in our diet.

What is GI?

GI stands for Glycemic Impact. This is a method of numbering or ranking carbohydrate foods to tell us if that food will make our blood sugar levels rise very quickly, moderately or very slowly.

The sugars in low GI foods are released more slowly into the bloodstream, causing blood glucose levels to rise and then fall more slowly than the foods that have a higher GI number. If we choose to eat more foods with a low GI, they will be absorbed more slowly and can help even out blood glucose levels.

High GI foods release their blood sugars more quickly, causing a “sugar rush.” You’re probably familiar with that high you get after eating a sugary snack -- that’s the simple sugars hitting your bloodstream all of a sudden! This sugar hit causes insulin to be released, and insulin’s role is to store the sugar away. This change from high blood sugar levels to low makes us crave sugary foods all over again.

Why go low GI?

Many studies have shown that foods with a low GI number satisfy our hunger for a longer period of time, and they also reduce our food cravings. And, that’s not all! Research has shown that there are other good reasons for eating low GI foods. When you eat LOW GI foods:

Your blood sugar levels rise more slowly

It can help keep the insulin levels balanced

It can help with the management of diabetes

You feel fuller for longer

Energy levels increase

It is a way to refuel your carbohydrate stores after exercise

It can help reduce cravings

And, what you really want to know…

Eating LOW GI foods can help you lose weight!

This is because you feel fuller for longer. Blood sugar levels rise more slowly, and insulin levels are better balanced -- making it easier for the energy released to be used rather than stored as fat. Eliminating the rapid changes in blood sugar and insulin levels can also make it easier for you to beat those cravings.

How can I follow a low GI plan?

Eating low GI does not entail a radical overhaul of your diet! As is so often the case with healthy eating, balance is the key. Eating low GI doesn’t mean only eating foods with low GI numbers. It’s about swapping high GI foods for lower GI alternatives whenever possible and trying to include low GI foods at each meal. You can still have medium and high-GI foods but in moderation. Making some simple changes can make a huge difference:

Reduce your intake of high GI carbohydrate foods such as sugar and sugary foods, sweets, cakes, biscuits and soft drinks.

Choose to eat low GI carbohydrate foods, which will take longer to digest, give you a more gradual rise in blood sugar levels and keep you satisfied for longer. Instead of high GI cereals such as cornflakes or Rice Krispies, choose a low or medium GI cereal such as porridge or oat cereal, All bran, Bran Flakes or muesli. Instead of high GI white breads, choose rye bread, pita bread, bran bread or wholegrain bread.

Swap high GI sticky rice for basmati rice or wholegrain rice.

Replace high GI carbohydrates like baked or mashed potatoes with pasta, barley, sweet potato or bulgur wheat. Of course, calories still count, but, if you are eating a low GI diet, you are going to feel fuller for longer. The control of blood sugars will help you avoid cravings, and you will have more control over your eating.

Getting to know GI

Glucose and white bread are set as the standards, and they have a GI of 100. All other foods are then measured against this.

Low GI has a rating of 55 or less

Medium GI has a rating of 56-69

High GI has a rating of 70 or more

Some Low GI Foods

Apples, cherries, grapefruit, grapes, pears, plums, oranges, strawberries, peaches.

Green vegetables such as broccoli and cabbage, mushrooms, onions, peppers and lettuce.

Pulses such as lentils, chickpeas and beans.

Sweet potato, rye bread, vermicelli and linguine pasta, noodles, brown basmati rice, barley.

All Bran, Muesli.

Crisps, plain, milk and white chocolate.

Low fat yogurt, milk, custard.

Some Medium GI Foods

Sultanas and raisins, pineapple, cantaloupe melon.

Beetroot, sweetcorn.

Grape nuts, porridge, puffed wheat.

Boiled new potatoes, white basmati rice, brown rice, pita bread, crumpet, Ryvita, wholewheat bread, couscous.

Honey & jam, digestive and rich tea biscuits.

Some High GI Foods

Dates, watermelon.

Parsnips, swede and cooked carrots, broad beans, pumpkin.

White bread, baguette, bagel.

Cornflakes, Rice Krispies, Shredded wheat, Weetabix.

Popcorn, wafer biscuits, jelly beans, sports drinks.

Answers To Your Questions!

I love my bread, cornflakes and potato. How can I live without them?

Well, of course, you can eat these foods, but don’t eat them at every meal and every day. Choose boiled new potatoes, brown rice and pasta, which has a low or moderate GI number, more often. These lower GI foods will be digested more slowly and satisfy you for longer and therefore delay the hunger pangs for longer.

So, should I stop eating so many bananas?

No! Bananas and the other fruits have a moderate GI number, but they still have a high nutritional value, and so we should continue to eat them. We would again say don’t eat them every day, and choose fruits with a lower GI number more often.

What about the vegetables with a high GI?

Same story! These vegetables pack a strong nutritional punch, providing fiber, vitamins and minerals. Once again, we would say don’t eat them every day. And, of course, do choose lots more of those with a low or moderate GI number.

What is the GI value for meat, chicken and fish?

Well, these foods do not contain carbohydrate, so the GI cannot be tested. These protein foods will not have an effect on your blood glucose levels and so lean meats, fish and poultry will be included in your meals.

Should I only eat foods with a low GI number?

No. Ideally, choosing the foods with a low GI number is best, but you don’t have to choose only these at every meal. That is because the effect of the low GI food at one meal will actually carry over to the next meal and reduce the overall GI for the day.

What else can affect the GI of foods?

When you look at the listing of low, moderate and high GI foods, you might be surprised at the category some foods fall into. This is because that rating will be affected by a number of other factors.

All of these factors will affect the overall rate of the GI

How foods are cooked.

Mashing and processing.

Combining foods with a different GI will alter the overall GI of a meal.

The amount of carbohydrate food eaten at a meal.

The amount of fat in the meal will affect the rate.

The amount of protein in the meal will affect the value

How do I put it all into practice?

To get the greatest benefit of GI, it is best to include a food with a low GI with every meal or snack to lower the overall effect on your blood glucose levels and gain all the other wonderful benefits!

You can now get your own personalized GI plan online! Just click here to find out more.



The information provided on is designed to support, not replace, the relationship that exists between a patient/site visitor and his/her health professional. This information is solely for informational purposes and does not constitute the practice of medicine. We encourage all visitors to see a licensed physician or nutritionist if they have any concerns regarding health issues related to diet, personal image and any other topics discussed on this site. Neither the owners or employees of nor the author(s) of site content take responsibility for any possible consequences from any treatment, procedure, exercise, dietary modification, action or application of medication which results from reading this site. Always speak with your primary health care provider before engaging in any form of self treatment. Please see our Legal Statement for further information.


How many diets have you tried in the past year?
Two to Three
Four to Five
More than Five
Total votes: 1024