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GI Information

What is the Glycemic index?

The Glycemic Index (GI) was developed in 1981. Dr David Jenkins was one of the key leaders and researchers in the development of the GI concept. The GI works by ranking foods containing carbohydrates on a scale from 0 to 100 according to their ability to raise blood glucose levels. Foods with a high GI of 70 or above on the scale, are rapidly digested and absorbed and this causes a distinct rise and fall, or spike in blood sugar (glucose) levels. Alternatively, low GI foods with a value of less than 55 on the scale, are broken down slowly and produce a more gradual rise in blood glucose levels. Due to their slower rate of digestion, low GI foods enable you to feel fuller for longer while sustaining your energy levels throughout the day. High GI foods get broken down quickly and are far less sustaining.

The 3 main GI categories are: 

• Low (GI = less than 55)
• Intermediate (GI = 56 - 69)
• High (GI = 70 plus)

The Tony Ferguson Weightloss Program

The Tony Ferguson Weightloss Program is based on the low GI principle. It works by energy (Kilojoule/Calorie) and carbohydrate reduction. Two meals a day are replaced with Tony Ferguson sachets and the third meal is a low carbohydrate, low GI meal option (protein and unlimited allowed vegetables). Allowed vegetables have a low carbohydrate content and low GI and may be consumed as often as desired throughout the day. People on the Program may also have 2 serves of low GI fruit and a few extras that are discussed with them upon registration on the Program.

Tony Ferguson sachets have a low GI of 22 and are nutritionally sound for weight loss as well as an ideal meal or snack option for those who would like to maintain their weight. The Tony Ferguson Cook Book was recently released. This book provides numerous low carbohydrate, low GI recipe suggestions not only for those on the weight loss Program but also anyone who would like healthy meal ideas. It has many tips for healthy eating and cooking and also suggests a number of substitute options for favourite foods. For example, Notatoes, is a cauliflower substitute for mashed potatoes.

The Tony Ferguson Weightloss Program helps you to make better food choices for weight loss and wellness. Carbohydrates are not completely restricted. Rather, the quantity consumed is reduced to enable weight loss. Eating low GI and limiting high GI carbohydrates is emphasized during both The Tony Ferguson Weightloss Program and The Tony Ferguson Maintenance Program (see next section for details). However some foods with low GI ranking are still not recommended while on the weight loss phase - corn, pasta, peas and kidney beans because they are too high in low GI carbohydrates for effective weight loss on the Program.

The Tony Ferguson Maintenance Program

The Tony Ferguson Maintenance Program has been designed for people who reach their goal weight on the Tony Ferguson Weightloss Program or need to take a break from losing weight but want to maintain their current weight. The Tony Ferguson Maintenance Program is also based on the low GI way of eating and continues to recommend a small amount of protein at each meal and a low glycemic carbohydrate intake. The Program re-introduces food from all food groups but helps you learn which are the healthiest choices and about correct portion sizes. A food plan is worked out and customized to your weight, age and activity level with a Tony Ferguson consultant and can result in several previously limited foods being reintroduced in small amounts i.e. traditional rolled oats for breakfast or sweet potato for dinner.

The Glycemic Index and Health

Insulin is a hormone secreted by the pancreas (an organ of the body like the heart or liver) that allows glucose (sugar with a GI of 100) to enter the cells where it is used to sustain everyday activities. The continuous consumption of high GI foods creates a larger demand for insulin to reduce blood glucose spiking which can eventually exhaust the pancreas and in susceptible people combined with other factors may lead to insulin resistance and diabetes.

There are many proven health benefits associated with adopting a low GI way of eating and this is why the Tony Ferguson Weightloss Program follows this principle. In combination with other lifestyle factors, low GI eating has been shown to improve blood glucose levels in people suffering from diabetes, to help avoid the onset of heart disease as well as playing a key role in weight control by helping to manage appetite levels and delaying hunger.

Glycemic Index Foods

The Glycemic Index does not rank all foods. It can only be applied to foods with a reasonable carbohydrate content. Most vegetables (but not potatoes which are high in carbohydrates and have a high GI) and some fruits contain very little carbohydrate per serving, or have very low GI values. GI values vary for different fruits and starchy vegetables but most dairy products have a low GI. Foods such as cheddar cheese, oil, most meats, fish and eggs contain little to no carbohydrates and therefore do not have a GI ranking. The GI refers to all carbohydrates and sugars, for example lactose (a milk sugar) has a low GI rating of 46 and fructose has a rating of 19. The GI also applies to any diet that contains carbohydrates i.e. a vegetarian or lactose free diet.

The GI can vary between different varieties of a food. For example multigrain bread has a lower GI than wholemeal, white and Lebanese bread.

Several factors can influence a food's GI, such as fat content. For example, potatoes have a higher GI than chips as chips have added fat. However the fat content of chips make them an unhealthy option. Another example is chocolate, some chocolate bars have a low GI due to their high fat content and again the low GI rating does not make them a healthy choice. Other factors that can affect the GI rating of a food are ripeness and processing which can increase the GI. For example, the longer you cook pasta, the higher its GI will be, to an extent. Some foods are naturally high in acidity e.g. berries. Acidity helps lower the GI rating. There are also methods of reducing the effect of high GI foods. For example, by eating a low GI food with a high GI food in the same total quantity, the effect on blood glucose will be lowered somewhat by the low GI food. However doubling up on either low or high GI food will raise blood glucose higher than a single serve and will take longer for levels to return to normal. So a food having a low GI does not mean you can eat more!

Here are a few examples of different types of foods and their GI ranking;

Note: Foods with little or no carbohydrate content do not have a GI value. They would be considered low if to be categorized. These foods are usually defined by other nutritional properties e.g. fibre, protein or fat.

Food	GI Rating	GI Category
Cereal
Cornflakes	77	High
Coco Pops	77	High
Guardian	37	Low
Fruit loops	69	Intermediate - borderline high
Fruit
Banana	52	Low
Strawberries	40	Low
Watermelon	77	High
Apple	38	Low
Peach	42	Low
Grapes	53	Low
Oranges	42	Low
Lemons	-	Little or no carbohydrates
Prunes	29	Low
High Carbohydrate Foods
Pasta (wheat)	40-50 (varies)	Low
Pretzels	83	High
Rice Crackers	91	High
Jasmine Rce	89-109*	High
White Bread	70-80	High
Beans
Kidney beans	36	Low
Broad beans	79	High
Meat/Eggs
Chicken	-	Little or no carbohydrates
Steak	-	Little or no carbohydrates
Lamb	-	Little or no carohydrates
Pork	-	Little or no carbohydrates
Eggs	-	Little or no carbohydrates
Vegetables
Spinach	-	Little or no carbohydrates
Pumpkin	75	High
Potato	70-101*	High
Tomato	-	Little or no carbohydrates
Sweet Potato	46	Low
Parsnips	97	High
Baby Marrow	-	Little or no carbohydrates
Liquids
A glass of milk	27-34	Low - high carbohydrates
A glass of fruit juice	37-53	Low - high carbohydrates
Water	-	Little or no carbohydrates
Oil	-	Little or no carbohydrates

Last updated 11/16/2009 1:11:47 PM