Jump to ratings and reviews
Rate this book

The G.I. Diet: Glycemic Index

Rate this book
If you understand a traffic light, you’ll understand this powerfully effective low-glycemic diet.   It’s the easiest, most satisfying eating plan possible. Both a New York Times and Wall Street Journal bestseller, here’s the book that  explains how to lose weight permanently without feeling hungry, counting calories, or jeopardizing your health. Based on the Glycemic Index, or G.I., the breakthrough nutritional discovery that measures the speed at which the body digests food and the impact it has on weight and well-being, The G.I. Diet organizes food into color-coded categories according to their G.I.  Red: Avoid.Yellow: Eat occasionally.Green: Make these foods the centerpiece of your diet. And that’s it. No more guesswork, no more formulas, no more fads. The G.I. Diet guides you to permanent weight loss as well as increased energy and a decreased risk of heart disease, stroke and diabetes. This revised and updated edition includes more comprehensive food lists; inspiring success stories; new tips on dining out; motivational help; plus recipes, snack ideas, a shopping list, and more. 

243 pages, Kindle Edition

First published January 1, 2002

225 people are currently reading
306 people want to read

About the author

Rick Gallop

24 books4 followers

Ratings & Reviews

What do you think?
Rate this book

Friends & Following

Create a free account to discover what your friends think of this book!

Community Reviews

5 stars
145 (26%)
4 stars
160 (28%)
3 stars
163 (29%)
2 stars
63 (11%)
1 star
26 (4%)
Displaying 1 - 30 of 37 reviews
Profile Image for Arah-Lynda.
337 reviews614 followers
April 5, 2012
The results are in:

Blood sugar……..check

Blood pressure…….check

Weight Loss…….16 lbs,

So informative and easy to use.

Red-light

Yellow- light

Geen- light

Simple and readily accessible.

Any idiot could use this guide successfully, but yeah…. it’s tough.

I am going to order his cookbook now and work on the next 15.

See ya….
Profile Image for Daniela.
180 reviews
June 30, 2011
This book offers an easy explanation to why certain foods get deposited into you fat cells and others not (as easily). It's the science behind similar books and gives very specific instructions on how to change your diet for good to never having to worry about blood sugar, energy loss due to wrong food consumption and weight gain again. It gives detailed lists of foods that are Bad, Good and Best for those trying to follow this eating habbit, because that's what this could become and quite easily so.

There is no cutting out any food groups, just eating the right variety of it and the right proportion on your plate.

I have lost 10 ponds with no effort at all and basically went right to phase two of the proposed plan as I didn't have a lot of weight to loose. So I happily even had my creamer in my coffee (both actually forbidden) in the morning, a glass of red wine twice a week. In between I even had Birthday Cake and a couple of Ice Caps... the reason I didn't follow the G.I. Diet to the T is because I researched the issue after finishing the book and found that not only is each food's glycemic index important, but if you are having it in combination with other foods G.I. levels can balance each other out to form an all over lower (or higher as the case may be) glycemic load. So that is one factor that the book didn't touch on and that really should be added to eliminate the thought that Watermelon (e.g.) isn't good for you. All in all this book is an eye opener though. Having grown up with German grey bread with lots of whole grains like sunflower seeds etc. in it, I found the switch to TRUE whole grain bread so easy (even though it's not as easily found in North America's supermarket isles), that I know I can follow this closely for the rest of my life.

Highly recommended for people who don't want to go on a diet, but make a change in their diet that gets them thin and keeps them so. Follow it up with the Glycemic Load Diet by Rob Thompson and and whole new world of eating habbits will open up for you...
Profile Image for Joy Weese Moll.
401 reviews107 followers
February 15, 2012
This is a slim, quickly read, volume with a straight forward diet. To lose weight, eat the foods in the green (for ‘go’) list. To maintain weight continue to eat foods on the green list and add a few on the yellow list. Red items should be eaten rarely, if at all. The green foods are low on the Glycemic Index and/or low in calories.

Like all the best diet books, The G.I. Diet has some wonderful tips. Here’s my favorite from this book, “Try adding what my friend calls a special ‘spa’ day to your week—a day when you are especially good with your program. This gives you some extra credit in your weight-loss account to draw on when the inevitable relapse occurs.”
Profile Image for Patty O'Hare.
7 reviews7 followers
December 4, 2014
I lost 14 pounds and will never go back to how I use to eat. Not a calorie counting diet but more of a "when and what to eat" plan. Consider reading this if you are an individuals who has diabetes in your family. This book caused me to reconsider a more serious effort towards "eating clean". Very easy to understand and implement. However, if you need help with emotional eating or other psychological aspects of eating, that isn't addressed here.
Profile Image for Christine.
43 reviews
May 9, 2018
I was curious about this plan because it was what experts say is the best for diabetes. It is interesting how the "plan" has shifted focus from diabetes to "weight loss". Maybe it is to get non compliant diabetics on board. My biggest gripe about this book is their favorite sweetner is SPLENDA.....for real???? Unfortunately this set the tone for me. I continued reading and will adapt some ideas however as I make it a hobby to read nutrition books,this was less than stellar. Splenda......good god!
Profile Image for Jennifer Barr.
143 reviews6 followers
January 28, 2018
Really disappointed with this. His information is pretty outdated. He doesn’t mention anything about glycemic load compared to glycemic index. So basically he believes that eating watermelon will make you fat, and his info on saturated fat is wrong. So all the recipes are both low carb and low fat, not exactly appetizing.
Profile Image for Sarah.
1,444 reviews27 followers
May 28, 2021
This one is harder to rate...G.I Diet is very…different from the other diet and cookbooks I have been reading. Keto, Paleo and Intermittent Fasting are all pretty anti-processed carbs and anti-snacking. Don’t get me wrong, Keto and Paleo will give you healthy snacking things (think a handful of nuts) if you absolutely cannot handle the hunger pangs when easing into the change or whenever you have a hollow leg. But G.I. …G.I. is basically the polar opposite of I.F and is like the annoying relative to Paleo and Keto.

I.F. wants you to cut down. Have an eight hour or less eating window. Drink tea or coffee plain but get those caffeine and anti-oxidants in there. Don’t snack because constantly grazing keeps your insulin level elevated and leads to insulin resistance. Avoid the majority of carbs and only eat them once a day, preferably. Give your pancreas and liver a break, basically.

G.I. is 3 meals, 3 snacks every day. Carbs are fine if limited per meal. Artificial sweeteners are fine and therefore diet pop/soda is fine. Eat ALL the veggies you want. Eat whole fruit and berries.
I.F. tells you that dieting is more than calories in and calories out. You are competing against your internal thermostat like weight controller. What you eat, when you eat, and how often you eat are key tools in your arsenal. Food and exercise are only roughly 20% of your factors (exercise is 6-10% of your calories out if you go hard) for weight loss.

G.I. is 100% calories in and calories out. What you put in and how much you exercise are key factors in weight loss (10% exercise, 90% diet), classic dieting info that Jason Fung (I.F. dude) goes out of his way to blow out of the water. So it’s interesting to compare the two. Gallop has you calculate your BMI and then find your ideal BMI and calculate your needed weight loss to hit that goal. Phase I is set to begin…oh wait no.

Throw everything out of your house the isn’t a “Green Light” food. Don’t store it, throw it away or give it away. Avoid people and places that don’t support your diet. Find yourself some diet cheerleaders. Log your progress weekly. Set up a rewards system for yourself. Okay, NOW phase I.

The first three four breakfast items in the small recipe section would make a Keto person roll in their grave, even though they are alive. Carbs. Carbs. Carbs. With almonds, fruit/berries, low-fat/ no fat dairy. The steel oat bit does redeem a bit though for the others. From there is goes into more traditional breakfast meals for the Keto and Paleo people, eggs, veggies, cheese (low fat).

Then there’s the normal salads, dinner ideas, blah blah blah. Random question thanks to this cook book…who puts raisin and apples in there chicken curry????

Basically, the last 142 pages are some recipes and phase 2 and graphs. At page 148 you are already through the recipes and the basics of phase 2. It’s interesting that he continues and gives you tips and trick for fast food, and restaurants, going so far as to talk about recommended orders by mealtime. Not something you normally see. Interesting. He also talks about emotional eating, some more tips and tricks for curbing your eating. Then at page 196 you get into the food graphs. This is interesting because they talk about foods that are Good light , Yellow Light and Red Light. What I find interesting to that there is a recipe for muffins that APPEAR NOWHERE IN THE MUFFIN SECTION!!! Commercial ones are listed as red light…nothing on the ones in the book our any others.

The is a brief works cited page, a page where he toots his own horn and NOWHERE can I find anything that gives him creditability. He has a degree in Advertising and...business? and works for the Heart and Stroke Foundation. That's it. Did it work for his 20 pounds? He says yes. I guess if you fill up with 8 oz of water and half your plate is veggies it might keep you full enough despite the 4oz of meat/protein allowed per meal. *shrugs*

Will I be trying it? Probably not. It reminds me a lot of the 21 Day Fix Diet I did for many months where I ate a lot of salad, abused my body to the point I couldn't move much and generally hated every second of it (I did skip the approved protein shakes though, cause I can't afford that stuff. Went for cheap in store stuff). For a diet that is supposed to have results in 21 days...it didn't work and i can't imagine this would work well. I will be taking notes on the green light foods though and comparing them further to other diets I have been entertaining (Paleo, keto). I do like the idea of keeping the insulin levels low to deconstruct the tolerance that I'm pretty sure I have.

2.5 stars I think. It may work for some people, but I'm not going to be trying it just yet.
2,271 reviews22 followers
September 21, 2022
This book offers an uncomplicated, long-term approach to managing your weight based on the glycemic index (referred to as G.I.) of foods. The author, a cardiologist and former President of the Heart and Stroke Foundation of Ontario, was forced by a back issue to stop his morning jog and quickly found himself putting on weight. When he tried conventional diets, he failed to stick to them, always hungry and feeling deprived. He also found counting calories, points, or carbs too time consuming for his busy schedule. He was lethargic and lacked his usual energy until he finally found a way to lose weight and keep it off by adopting a diet based on the Glycemic Index of foods.

In the first chapters, Gallop describes why people have gained so much weight in the past twenty years and reviews the key components of food, the fats, carbohydrates and proteins with which we are all familiar, explaining how they function in our digestive systems. It all leads to the conclusion that the key to losing weight, is to eat low-G.I., low calorie foods.

In subsequent chapters he includes charts to help readers determine their most desirable weight and describes the basic two-phase approach to the diet. It begins with Phase 1, reducing the number of calories consumed by eating low-G.I., low calorie foods and when the desirable BMI is reached, moves to Phase 2 which evens out the number of calories consumed and expended.

In Phase 1 he simplifies the approach by identifying red light foods, the high G.I., higher caloric foods that are also high in saturated fat and are to be avoided. Yellow light foods are mid-range G.I. foods, to be avoided in Phase 1 and treated with caution in Phase 2. Green light foods are low-G.I., low in saturated fats and low in calories; these are the foods that will help you lose weight.

Gallup speaks about portion size, explains the best time to eat and provides some meal ideas. He also addresses the challenges of eating out, gives hints on how to stay motivated over the long term and explains the important role of exercise in health.

The appendices are filled with more tips and help including a complete G.I. diet food guide, shopping lists and the ten golden G.I. diet rules, succinctly summarizing much of what he has written in the book.

This is a very helpful little volume that provides a way of eating that banishes the need to count calories, never leaves you hungry and helps you recover the energy levels you enjoyed in the past. Those who have failed at other approaches at weight management might find this the ticket they need.

Profile Image for Ouri.
36 reviews6 followers
November 14, 2019
Easy to follow and read, written in plain English. Was able to get through this in a day. Good information in here about how a protein heavy / meat based diet can be problematic, which are becoming popular today. I personally don’t jive with the recommendation to consume lower fat alternatives to normally fine foods like eggs(egg whites vs. whole eggs) I am not trying to lose weight, so I’m probably not the target audience for this, but I still found a lot of useful tips in here and will follow some of the principles as I noticed high glycemic foods spike my insulin and make me shlumped. They also bloat me. Prior to reading this book it was hard to conceptualize what is where in the G.I. Scale , but the system they use in here makes it easy to understand. It’s pretty straightforward - avoid processed foods, make 50% of your plate veggies, 25% protein , 25% low GI grains or beans. Thanks to this book I’m going to continue to eat fruit to my hearts delight (apparently grapefruit, grapes, apples, berries, oranges and peaches are low GI), and try to eat more veg. But nothing can make me give up saturated fats. I personally don’t like also how they recommend PUFAs like canola oil over animal fat.. I think going for low fat alternatives to things is one way to make people feel like they’re depriving themselves and end up snacking more on things like say nuts or fruits. This book lowkey feels like a shill book for the American concept of healthy eating which is inducing grain brain and “low fat” alternatives while consuming shitty dairy and artificial sweeteners and “energy bars”. No thanks on that
10 reviews
February 22, 2019
After first becoming familiar with the Glycemic Index from reading Perricone in my late teens & early 20's, seeing a book exclusively about GI intrigued me. Since my lifestyle with work is a bit out of whack, I figured I'd catch up again on GI since my food intake is something I can control more than my work hours and free time. I have digestive issues and have been steadily gaining weight. That all aside...

THE BOOK: As a previous reviewer stated, this book does seem outdated... and it oddly has points that are either completely contrary to current research (this book recommends skim or low-fat everything, but good fats are good for you!) or what I've read in anti-inflammatory reading. That's not to say this isn't a good read. I imagine that for someone that eats incredibly poorly, this will steer them in the right direction and the guides are relatively easy to follow. And I bet if you do follow the recipes, you will see some results.

Personally, I wouldn't follow this book 100%, but I read it at face value in conjunction with another book about eating to create alkalinity in the body ("Get Off Your Acid" by Dr. Daryl Gioffre). They do agree in some aspects. I've also read other books that correlate a little more closely with the latter book and will follow through with my Anti-Inflammation Diet books and The Dental Diet book. I want to see where they all agree.
Profile Image for Preeth.
29 reviews
August 3, 2021
A quick and easy read on glycemic index diet is an eating plan based on how foods affect your blood sugar level. The complex functioning of the macro nutrients and their functions in our body is explained well in layman's term. For a beginner to a GI diet, this book provides a lot of information.
Although I read the updated version of the book, there was no mention of glycemic load (GL), a numerical value that indicates the change in blood glucose levels when you eat a typical serving of the food. And I quite don't agree with adding artificial sweeteners in the GI chart. A great collection of good recipes to follow. But I haven't tried out any so far.
Profile Image for SJ.
29 reviews
November 26, 2021
While the recipe section of this book is actually pretty good, and there is some good information in it, this book made me angry.

The shove-it-in-your-face, constant repetition of the DON'T DO THIS, DON'T EAT THIS, NO, NO, NO writing style put me on edge. I was immediately reminded of the gym trainer who thinks that insulting folks as they exercise is "motivating." By all means, if you DO find that motivating, or you prefer a literal red list, yellow list and green list visual way of learning, go for it. This might be the book for you.
Profile Image for Mickalene.
301 reviews
October 6, 2022
Ok. I liked the books format, color rating of foods, some of the recipes and overall explanation of GI. Enough info to get people started and to begin understanding GI, but I felt it was too strict to be very helpful and some of the info seemed outdated.
Profile Image for CindySR.
594 reviews5 followers
July 3, 2017
I like the red/ yellow /green food lists. Helpful.
Profile Image for Judy.
432 reviews7 followers
July 25, 2018
Good book but more for vegans would be nice. The author says she never met a large vegetarian ! Well she should visit the lesbian community sometime !!!
Profile Image for Joanna.
347 reviews1 follower
June 9, 2019
A great balance of science, recipes, guides, and shopping lists.
Profile Image for Rachel Meyers.
Author 2 books11 followers
February 7, 2022
Jane McClelland suggests the low gi diet for cancer but I can't imagine eating margarine and low fat would be good for you. This is more of a weight loss book than a health book
Profile Image for Gill Osmant.
49 reviews
September 4, 2023
Very comprehensive approach. Not a diet but a way to live . Reçu you read this one
Profile Image for Helen.
3,600 reviews85 followers
July 2, 2024
The author is someone with lots of information about medicine, especially about heart disease. He's written a useful way to think about the foods we eat. Easy to understand and healthy if you do it!
Profile Image for Sean O'Reilly.
106 reviews3 followers
December 7, 2013
At just 156 pages this is a quick to read book. Previously I knew very little about the GI concept although I had got the impression that it would be quite complex. In fact it is extremely straightforward.

The GI is a score based on how quickly the body converts a food into blood glucose. My preconception was that, in order to follow the GI Diet, you would constantly have to be checking the GI of different foods. However this book divides foods into green, yellow and red-light categories; it is then simply a case of eating green-light foods for weight loss, more green light foods with some yellow light foods for weight maintenance, and avoiding red light foods pretty much all the time. In addition there is a strong element of portion control involved in the diet.

For me this diet would not require a major shift from what I am eating at the moment (I am currently calorie counting although my eating habits are also influenced by my previous use of the Slimming World diet). Nevertheless I have a few issues with the GI Diet and with some weaknesses I feel that this book has.

Firstly I feel that the diet is, in some ways, too restrictive to be realistic. For example Gallop advocates zero alcohol consumption during the weight loss phase of the diet. Gallop gives an example of somebody wanting to lose 20 pounds at a pound a week needing to give up drink for a few (five?) months. I need to lose 60 pounds. There is no way I am giving up drinking for over a year. To be fair Gallop talks about following the plan for 90% of the time and allowing oneself 10% 'wriggle room'. However, to my mind, this is too vague to be helpful. The fact that the GI Diet does not require you to count points or calories is sold as a plus point, but I can't help feeling that some way of counting how much you have 'wriggled' is helpful in staying on track.

Secondly this book has very little to say about dealing with the reasons that so many people find it difficult to stick with a diet. Gallop frequently says that, once you have adjusted to this new way of eating and lost weight, you will not want to go back to your old habits. Having previously lost 6 stone and run a marathon, and having believed that I would never go back to my old habits, I know just how easy it is to slip back into destructive ways of eating. I am certain that the GI Diet offers an eating plan which is sustainable for a lifetime. I am extremely doubtful of it's claim that this lifetime change is simple to sustain, certainly not for anyone who has serious issues around food and eating.

I will certainly do some more reading around the GI Diet; and this book has already got me thinking about some of current eating habits. At the moment though I am not completely convinced.
Profile Image for Matt.
80 reviews
February 19, 2015
This book educates the reader about the importance of glycaemic index in food and how to permanently change your lifestyle to keep your ideal weight for life. Unlike other diet books I've read, this book covers more than just the initial weight loss. It achieves this in two phases: the first covers the steady, safe and sustainable reduction of weight, and the second covers how to maintain your ideal weight once you reach it. This isn't about a crash diet, and doesn't require any dietary replacements or strange supplements.

In addition to the weight loss and maintenance phases, it gives advice on what to do when you get complacent or when you have bad days. The author knows it will happen, that it's not cause for alarm or a reason to give up, and shows how to remedy the situation. The GI of foods are arranged in a traffic light colour system to indicate red (high-GI), amber (moderate-GI) and green (low-GI) foods. At its simplest, the weight loss phase recommends eating only 'green light' foods and the maintenance phased allows 'green light' and 'amber light' foods ('red light' foods are considered unwise regardless of your BMI; not an unfair assessment). It is easy to understand and can be integrated into everyday life -- including the inevitable pub lunches, restaurants and takeaway. And it doesn't unrealistically assume that you live like a monk or stick religiously to it all the time.

For the sceptically-minded, this book contains none of the red flags normally associated with nutritional and dietary advice, no unsupported claims, no supplements or special products need to be purchased, no denial of important food groups or dietary diversity, and it was written by the former president of Ontario's heart and stroke foundation. Although a proper review would need to be based upon giving the diet a full workout, after reading it through I'm confident this book is worth your time.
Profile Image for Camille Baird.
255 reviews3 followers
May 6, 2013
Excellent book.. misleading title..not really a diet.. a way of eating. Maybe Diet attracts more people. Easy to read. easy to track your foods. easy way to learn how to modify eating and although your body will rebel for probably the first 2-3 weeks you will feel so much better and it won't be that hard. really.. you will need to not keep the bad foods around. think of yourself living in a broken food culture and you are relearning the way to eat.
I really liked it.
Profile Image for Liz.
278 reviews
June 8, 2009
The reading part of the book has some good, informative guidelines. However, the recipes I've tried so far seem bland, extremely vegetable-y, and most of them seem to taste similarly. I do understand that the point of this particular diet is to increase your vegetables, but I wasn't too impressed with these recipes in general.
Profile Image for Alyssa.
163 reviews10 followers
October 5, 2010
This book explains some interesting things about the glycemic index and how it works, but its reliance on artificial sweeteners seems like a cop-out. I'm not so sure about a nutritional plan that puts diet coke above cantaloupe...

Overall, it had some useful information if one is selective, and it has a great collection of easy recipes, but I wouldn't live by it.
Profile Image for Tina Grozelle.
33 reviews2 followers
July 15, 2013
Some good information which is helpful for making daily eating decisions. Like most other health related books....if I followed the advice I might actually lose weight! It is a practical and simple read with some repeated information only moderately irritating. I do plan on making slight changes to my habits based on information from this book.
Profile Image for Matt Stivers.
9 reviews1 follower
February 2, 2009
This gives the basic foundation of the glycemic index diet. He presents things in an easy to follow manner, and it tells you all you need to do. There aren't but a hand full of recipes in the book, so you'll be wondering what to eat after a while.
165 reviews3 followers
August 30, 2014
Fabulous, easy to follow diet plan that is now he basis for many of the most popular diets. For diabetics, it is a very good, safe plan, and works well for others wanting to be healthy without being too extreme.
18 reviews
January 11, 2008
Very worthwhile book by Canadian physician on how blood sugar levels have major effect on weight levels. Easy to follow charts of foods to embrace and avoid.
Displaying 1 - 30 of 37 reviews

Can't find what you're looking for?

Get help and learn more about the design.