Archive for December, 2009

The Glycemic Index

Posted: December 30, 2009 by The Vegetarian Barbarian in Nutrition Conversations

By now you must have heard the term The Glycemic Index (GI). For example, “We use the power of the Glycemic Index to help you lose 100 inches and 200 pounds in just two weeks!” It has been referenced in diets, meal plans for diabetics*, stamped on labels, and you have probably seen it splattered on magazine covers. Do you really know what it is, how it works and whether utilizing it as a weight-loss tool is viable? Before we campaign for GI we should understand what it is and why it is used.

The Vegetarian Barbarian has stated before that we have a distaste for terms being thrown around with little explanation or expertise behind it. The purpose of this article is to provide a little clarity.

What everyone wants to know is whether or not the GI can be utilized as a weight-loss tool. The answer is a resounding maybe. Let’s start with the basics and then discuss the GI’s practicality.

Glycemic Index (GI): A scale that rates all carbohydrate-containing foods based on how they would affect your blood sugar level after you ate them.

That’s all it is. The deeper dive tells us that the GI actually shows the increase in blood glucose levels over a baseline level during a two-hour period following the consumption of a defined amount of carbohydrates (typically 50 grams). This increase is then compared with the value assessed from the same amount of carbohydrates in a referenced food. Here’s a simple example. Let’s say that 1g of sugar contains 10g of carbohydrates and use that as our baseline. We eat the sugar and see how it affects our blood glucose levels and place that rate on the GI. Now let’s ingest 10g of carbohydrate from honey and see how that affects our blood glucose levels. GI would rate the honey against the sugar (the winner is sugar by the way).

Some foods cause a rapid rise and fall in blood sugar levels (also known as blood glucose levels) and thus have a higher rating. Others foods cause a slower and extended rise (typically with a lower “peak” and a gradual fall).  Basically if you eat a handful of sugar (shame on you) you will spike your blood sugar and then that spike drops off quickly. If you ate some beans it would take longer for it to affect your blood sugar, wouldn’t affect it as dramatically and the “peak” would trail off gradually. The glycemic index was developed to provide a numerical value to represent the speed of the rise and fall. When given a numerical value you can easily compare two foods.

So why are we giving out all this information around blood glucose levels and absorption rates? Well, glucose absorption rates appear to be an important parameter in controlling homeostasis of our blood glucose and insulin release which in turn may help maintain our weight and stave off obesity. We like that – it makes the Vegetarian Barbarian happy. The official caveat here is that with most science which discusses weight loss nothing is 100% certain. However, there has been intense research in the last few years on the implications of consuming high glycemic index foods for coronary heart disease (CHD) and obesity.

It’s time to put the GI into practice. Let’s take a look at some common foods and where they rank on the Glycemic Index! The referenced food for this chart is white bread which has a score of 100.

FOOD

GI

White
Bread, refined flour

100

Spaghetti,
Durum Wheat (boiled):

91

Coca
cola:

90

Raisin
Bran:

87

Brown
Rice:

72

Baked
beans:

57

Lentils:

40

 

Were you able to read the chart, understand the numbers and draw the comparison to white bread? If not, it’s pretty simple. The carbohydrates in white bread are more readily absorbed into the bloodstream than any item on this chart if you ingest similar amounts (50g for example). If you happened to eat a meal that contained 50g of lentils and 50g of white bread the lentils would raise your blood glucose levels 60% slower than the white bread. We also believe that it would be a fairly awful meal.

In general, non-starchy vegetables, most fruits, legumes (dry beans), and milk tend to have a lower glycemic index number. Items milled from refined white flour such as white bread, crackers, and cornflakes are high-GI foods. Can you guess what the GI rating of table sugar and an artificial sweetener would be?

They are 100 and 80 respectively.

 

FUEL FOR EXERCISE:

 

We suggest eating some carbohydrates before working out for fuel. We advocate the use of low to moderate GI rated carbohydrates over higher ranked foods. We prefer our energy to be sustained throughout our workouts instead of getting a huge spike that drops off as we go. It is as simple as that. From the nutritionist’s standpoint, it is preferable because the hyperinsulinemic effect of high-GI foods rapidly reduces blood glucose and also suppresses release of stored fatty acids. The average Joe version is that we don’t like having a sugar crash when we have heavy weights lifted above our heads.

This is where we plug The Vegetarian Barbarian Protein Bar (you knew it was coming). The VB Bar is low-glycemic. Most bars have fairly low carbohydrates that come from wheat germ and dried fruit. We often fuel up before a workout with half of a bar (Amy does, Scott eats a whole one) and then finish the bar immediately following a workout. We eat small meals frequently throughout the day which allows us to reduce the amount of carbohydrates that we eat at one time. Choosing foods lower on the GI (that are less processed – like a VB bar – Shazam!) or lentils instead of bread will give you a timed-release response to digestion that keeps your blood sugar levels more even. Since carbohydrates are digested more rapidly than protein or fat, when you eat a combination of foods like an apple with almond butter or the VB Cinnamon Roll protein bar (they’re delicious), you slow digestion down. Ultimately you are getting a slow release of sugar into the bloodstream and are helping to prevent weight gain.

 

Additional Factoids:

 

The Glycemic Index is a marvelous tool for ranking carbohydrates. However, it is currently only in its infancy regarding health benefits. More research is necessary to make it a truly valid, reliable, and an applicable teaching tool. The simple facts still remain:

  • 20% of Americans’ Calories Come from High Carbohydrate Foods
    • Example: cakes, cookies, pies, pastries, ice cream, sugar, candy, soda pop, and chips.
  • Fresh Fruits, Vegetables, and Whole Grain Products are Nutritionally Superior to Highly Processed Foods
    • Example: Whole Wheat Breads and Pastas, Brown Rice, and Wheat Germ (Found in VB bars)
  • Limiting Total Carbohydrates Helps Control Blood Sugar Levels
     

    • Stop Cutting Carbohydrates Out Completely!
  • Consuming a High-GI Food with a Low GI-Food May Give a Moderate GI Response.

The bottom line is that you probably don’t need a complicated rating system to confuse you about which carbohydrates to include in your diet. There’s enough misinformation out there already. Hopefully this small article
sheds some light on the newest fad in the nutrition world.

*For people with diabetes the glycemic index can be useful as one tool to manage blood sugar levels, along with glucose monitoring and monitoring total grams of carbohydrate. You should take the information with a grain of salt and always be guided by your Diabetes specialist.

 

By now you must have heard the term The Glycemic Index (GI). For example, “We use the power of the Glycemic Index to help you lose 100 inches and 200 pounds in just two weeks!” It has been referenced in diets, meal plans for diabetics*, stamped on labels, and you have probably seen it splattered on magazine covers. Do you really know what it is, how it works and whether utilizing it as a weight-loss tool is viable? Before we campaign for GI we should understand what it is and why it is used.

The Vegetarian Barbarian has stated before that we have a distaste for terms being thrown around with little explanation or expertise behind it. The purpose of this article is to provide a little clarity.

What everyone wants to know is whether or not the GI can be utilized as a weight-loss tool. The answer is a resounding maybe. Let’s start with the basics and then discuss the GI’s practicality.

Glycemic Index (GI):

A scale that rates all carbohydrate-containing foods based on how they would affect your blood sugar level after you ate them.

That’s all it is. The deeper dive tells us that the GI actually shows the increase in blood glucose levels over a baseline level during a two-hour period following the consumption of a defined amount of carbohydrates (typically 50 grams). This increase is then compared with the value assessed from the same amount of carbohydrates in a referenced food. Here’s a simple example. Let’s say that 1g of sugar contains 10g of carbohydrates and use that as our baseline. We eat the sugar and see how it affects our blood glucose levels and place that rate on the GI. Now let’s ingest 10g of carbohydrate from honey and see how that affects our blood glucose levels. GI would rate the honey against the sugar (the winner is sugar by the way).

Some foods cause a rapid rise and fall in blood sugar levels (also known as blood glucose levels) and thus have a higher rating. Others foods cause a slower and extended rise (typically with a lower “peak” and a gradual fall).  Basically if you eat a handful of sugar (shame on you) you will spike your blood sugar and then that spike drops off quickly. If you ate some beans it would take longer for it to affect your blood sugar, wouldn’t affect it as dramatically and the “peak” would trail off gradually. The glycemic index was developed to provide a numerical value to represent the speed of the rise and fall. When given a numerical value you can easily compare two foods.

So why are we giving out all this information around blood glucose levels and absorption rates? Well, glucose absorption rates appear to be an important parameter in controlling homeostasis of our blood glucose and insulin release which in turn may help maintain our weight and stave off obesity. We like that – it makes the Vegetarian Barbarian happy. The official caveat here is that with most science which discusses weight loss nothing is 100% certain. However, there has been intense research in the last few years on the implications of consuming high glycemic index foods for coronary heart disease (CHD) and obesity.

It’s time to put the GI into practice. Let’s take a look at some common foods and where they rank on the Glycemic Index! The referenced food for this chart is white bread which has a score of 100.



FOOD

GI

White
Bread, refined flour

100

Spaghetti,
Durum Wheat (boiled):

91

Coca
cola:

90

Raisin
Bran:

87

Brown
Rice:

72

Baked
beans:

57

Lentils:

40

Were you able to read the chart, understand the numbers and draw the comparison to white bread? If not, it’s pretty simple. The carbohydrates in white bread are more readily absorbed into the bloodstream than any item on this chart if you ingest similar amounts (50g for example). If you happened to eat a meal that contained 50g of lentils and 50g of white bread the lentils would raise your blood glucose levels 60% slower than the white bread. We also believe that it would be a fairly awful meal.

In general, non-starchy vegetables, most fruits, legumes (dry beans), and milk tend to have a lower glycemic index number. Items milled from refined white flour such as white bread, crackers, and cornflakes are high-GI foods. Can you guess what the GI rating of table sugar and an artificial sweetener would be?

They are 100 and 80 respectively.

FUEL FOR EXERCISE:

We suggest eating some carbohydrates before working out for fuel. We advocate the use of low to moderate GI rated carbohydrates over higher ranked foods. We prefer our energy to be sustained throughout our workouts instead of getting a huge spike that drops off as we go. It is as simple as that. From the nutritionist’s standpoint, it is preferable because the hyperinsulinemic effect of high-GI foods rapidly reduces blood glucose and also suppresses release of stored fatty acids. The average Joe version is that we don’t like having a sugar crash when we have heavy weights lifted above our heads.

This is where we plug The Vegetarian Barbarian Protein Bar (you knew it was coming). The VB Bar is low-glycemic. Most bars have fairly low carbohydrates that come from wheat germ and dried fruit. We often fuel up before a workout with half of a bar (Amy does, Scott eats a whole one) and then finish the bar immediately following a workout. We eat small meals frequently throughout the day which allows us to reduce the amount of carbohydrates that we eat at one time. Choosing foods lower on the GI (that are less processed – like a VB bar – Shazam!) or lentils instead of bread will give you a timed-release response to digestion that keeps your blood sugar levels more even. Since carbohydrates are digested more rapidly than protein or fat, when you eat combinations of foods like an apple with almond butter or the VB Cinnamon Roll protein bar (they’re delicious), you slow digestion down. Ultimately you are getting a slow release of sugar into the bloodstream and are helping to prevent weight gain.

Additional Factoids:

The Glycemic Index is a marvelous tool for ranking carbohydrates. However, it is currently only in its infancy regarding health benefits. More research is necessary to make it a truly valid, reliable, and an applicable teaching tool. The simple facts still remain:

  • 20% of Americans’ Calories Come from High Carbohydrate Foods
    • Example: cakes, cookies, pies, pastries, ice cream, sugar, candy, soda pop, and chips.
  • Fresh Fruits, Vegetables, and Whole Grain Products are Nutritionally Superior to Highly Processed Foods
    • Example: Whole Wheat Breads and Pastas, Brown Rice, and Wheat Germ (Found in VB bars)
  • Limiting Total Carbohydrates Helps Control Blood Sugar Levels

     

    • Stop Cutting Carbohydrates Out Completely!
  • Consuming a High-GI Food with a Low GI-Food May Give a Moderate GI Response.

The bottom line is that you probably don’t need a complicated rating system to confuse you about which carbohydrates to include in your diet. There’s enough misinformation out there already. Hopefully this small article
sheds some light on the newest fad in the nutrition world.

*For people with diabetes the glycemic index can be useful as one tool to manage blood sugar levels, along with glucose monitoring and monitoring total grams of carbohydrate. You should take the information with a grain of salt and always be guided by your Diabetes specialist.

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