I often refer to the GI of foods when writing posts and a couple of readers have asked me, “what is a low GI diet plan?” so I thought it would be a good idea to write a post on the subject for those of you that are interested.
I first became interested in the GI (glycemic index) of foods when I read the book The New Glucose Revolution many years ago. A low glycemic diet plan is the term for a weight-loss strategy that focuses on the blood sugar levels in the body. It uses the glycemic index as a guide to rank specific carbohydrates from zero to 100, based on the rate in which they affect your blood sugar levels.
It is claimed that by eating foods with a low GI you can reduce the rate of breakdown of foods, thus reducing the frequency of hunger in a day and also making blood glucose available at a steady rate, as opposed to having high spikes followed by lows. Many say that this aids in reducing blood sugar levels in diabetic patients, helps prevent insulin resistance (precursor to diabetes), and also helps in weight control. Recent studies indicate that a low glycemic index diet may also be effective in actually curing type 2 diabetes and coronary heart disease; however there is still much controversy surrounding this.
Foods ranked by the glycemic index are given the following scores:
- High – 70 and up: Examples include bagels, cream of wheat, white rice, graham crackers and watermelon.
- Medium – 56 to 69: Examples include couscous, sweetcorn on the cob, raisins and honey.
- Low – 55 and below: Examples include coarse barley bread, grapefruit, apples, chick peas and bananas.
You are not expected to eat low GI foods exclusively, but it is suggested that you avoid high GI foods where possible and incorporate some low GI ones in every meal. You can find more comprehensive lists here or here.
The Effects of Food on Insulin
I have studied the health and weight loss theories of numerous experts over the past year and it is amazing how they can vary in their opinions as to what is good and what is not. There are a few key core concepts, however, which they all agree on, and the adverse effects of our modern diet on our insulin levels and an individual’s ability to lose weight is one of them. It is particularly difficult with so many processed foods full of chemicals and hidden sugars.
Insulin is a natural hormone which helps the body to regulate the amount of glucose or sugar available in the bloodstream. The elevated secretion of insulin and the insensitivity of insulin receptors are some of the major causes of excess bodyweight gain and are major factors that have made it difficult for millions of people to effectively lose even small amounts of weight. When I attended the Jon Gabriel workshop recently, I learned about the nasty catch 22 about insulin resistance. If you are insulin resistant it makes it much more difficult to lose weight and being overweight is a major contributor to insulin resistance. Nasty, huh?
How does it actually work?
Whenever there is an excess amount of glucose in the blood, the body counteracts it by secreting insulin which consequently instructs the cells to take up the excess glucose and convert it to either glycogen for storage in liver and muscle cells or fat to be stored in fat cells. The major factors that can significantly influence glucose absorption include the glycemic index of the consumed carbohydrate food and also the co-ingestion of fats and proteins such as meat.
Generally, carbohydrate foods with a high glycemic index are very quickly absorbed into the blood and can cause a quick rise in blood glucose levels. While those with a low glycemic index are absorbed at a slower rate and cause a more gradual rise in blood sugar levels, thereby avoiding fat causing insulin spikes.
One thing that I find a bit tricky with this is that the GI rating can vary considerably depending on the ripeness, storage methods, cooking, and also the variety of the food. For example, this photo is one I took of the birds eating the figs on our trees. I used figs as my example, because I like the photo, even if it is a little out of focus, but also to make my point. I did a search for ‘low glycemic fruits’ then narrowed it down to figs. Several sites gave different results, ranging from 35 – 65. I have no idea what variety ours are, all I know is that they are delicious if we can manage to grab a few before the naughty lorikeets get them. And yes, to all my readers outside Australia, they really are that color.
What is the Glycemic Load
Glycemic load measures the effect of the total amount of a food on your blood sugar on a per serving basis. To find the glycemic load of any food or beverage, you can simply multiply the glycemic index by the number of carbohydrates per serving (grams) and then divide by 100. A lower glycemic load indicates that a food will stimulate less blood sugar and is a “good” carbohydrate. A higher one means it’s a “bad” carbohydrate.
Remember the following equations and numbers:
Glycemic Load = Glycemic Index x Grams of Carbohydrates/ 100
Low Glycemic Load = 0 to 10
Medium Glycemic Load = 11 to 19
High Glycemic Load = 20 and higher
The Glycemic Index and Weight Control
What many people don’t realize is that your blood sugar levels play a major role in your body. They affect your health, your energy, and even your mood. By understanding how certain foods or diets impact your blood sugar, you can use them to help you accomplish your goals of weight control. The glycemic index or GI diet can be compared to a round of golf, which means the lower the score, the less fluctuation it causes in your blood sugar. The number to remember for a GI diet is 55; foods that score a 55 or less are considered low glycemic and can be beneficial for your health and help you achieve weight control. Consumption of high GI foods can have the following negative effects on your body:
- They cause your blood sugar to spike. This spike is accompanied by an energy burst or a “sugar high”.
- The spike often ends up leading to a blood sugar crash, which depletes your energy.
- These fluctuations can lead to cravings and hunger pains, which typically results in people eating even more high GI foods. This creates a cycle in which your blood sugar is fluctuating greatly throughout the day.
These constant fluctuations can cause a multitude of health problems including diabetes, obesity, and even mood swings. By maintaining a more level blood sugar level, you can significantly reduce the spikes and crashes. By reducing the spikes and crashes, you reduce the cravings and hunger pains. By reducing them, you eat less throughout the day. I’m sure you get my drift. Also, the foods that are low glycemic are typically low in calories, so you are even more likely to lose weight.
As I have stated many times, I am not a medical specialist in any way shape or form, so for any of you who are interested in reading more on this topic, I have listed some good resources at the bottom of this article. Also, you can get The Low GI Shopper’s Guide to GI Values 2012: The Authoritative Source of Glycemic Index Values for Nearly 1,200 Foods by Jennie Brand-Miller, a worldwide authority on the glycemic index, for as little as $2.99 from Amazon.
From a personal viewpoint I am not following a low GI diet, but due to the lifestyle changes I have been making over the past year, I find that I am eating less high GI foods and more low GI ones by default. I also refer to the index periodically to see where it is possible to replace high GI foods with low ones without sacrificing flavor. A perfect example of this is bread. I have always loved sourdough and it has a lower GI than many other types of bread, so I make that my bread of choice whenever possible.
If you have followed a low GI diet plan or have had any experiences with eating according to the glycemic index, I would love it if you would share your experiences with other readers in the comments below. Here are some good sites for those of you that are interested in learning more.