Ask the Nutritionist: Dr. Getty's Forum for Equine Nutrition
Welcome to my forum.
Here you will find more than 6 years of questions and my answers. It is searchable and offers a great deal of information.
Currently, I am discontinuing new questions. This may change in the future, but in the meantime, please know that It has been a true pleasure serving you.
Take a look at my Nutrition Library and Tips of the Month for a variety of answers on selected topics. Be sure to sign up for my monthly e-newsletter, Forage for Thought.
I also have a growing number of recordings on "Teleseminars on Nutrition Topics that Concern You" as well as the new, Spotlight on Equine Nutrition Series -- printed versions of favorite teleseminars.
And finally, look for my articles in a variety of local publications and online newsletters, as well as the Horse Journal, where I am the Contributing Nutrition Editor.
All the best,
Dr. Getty
Hi Jane,
The glycemic load gives you a more accurate assessment than just the glycemic index because the GL takes into consideration the amount of the food the horse eats and the concentration of sugar in that food.
For example, if a carrot has 5 grams of sugar in 100 grams, and a GI of 72%, the GL would equal 5 X 72/100 (because the GL includes the amount of sugar in 100 grams of food). This equals a GL of 3.6%. That is quite low.
But if the horse has three carrots, the GI rises, making the GL rise as well.
So, I believe that these numbers are nice to look at but you have to use your common sense. One cookie, when you're on a diet, may not hurt, but the whole bag... well... even if the GL is low for one, it is still fattening to eat the whole bag!
By the same token, a high sugar grass may have a low GL, but if the horse grazes on it for hours and hours, well... we can have a problem.
So, it's true... the more sugar there is in 100 grams of a feed, the higher the GL. But we cannot discount the glycemic index which looks at the level of glucose in the blood per 50 grams of feed. As the horse eats more, the GI goes up. As the GI goes up, so does the GL.
So bottom line... too much of a good thing can be a bag thing!
All the best,
Dr. Getty 
Author of Feed Your Horse Like A Horse
)http://horseconsult.wordpress.com/2012/02/03/glycemic-index-vs-glycemic-load/
Article:
http://www.thepenzancehorse.com/2011/ARTICLES/Glycemic%20Index%20vs%20Glycemic%20Load.pdf
Blessings,
Jane
Where are you from? Bayfield, CO
Hi Jane,
I'm glad to help. Sometimes, a dose of common sense along with the numbers, is the best approach.
All the best,
Dr. Getty
Author of Feed Your Horse Like A Horse
)Where are you from? Bayfield, CO