Abby Housefield

Written by Abby Housefield


The Truth about Sugar for Runners

On average, Americans consume more than 22 teaspoons of sugar each day for breakfast. That is 355 calories from sugar and more than double the amount of sugar a person should have in an entire day. Today, on average, every man, woman, and child consumes 140 pounds of sugar in one year. These statistics do not exempt the gel-sports-drink-energy-bar-loving runner.

I found myself with a little time in athlete’s village, while I waited for the Boston Marathon to start, and examined the ingredient list on one of the sponsor’s energy bars. In the ingredients there were five different forms of sugar: cane sugar, maltodextrin, fructose, dextrose, and sugar. These all added up to 26 g of sugar and 45 g of carbohydrates, which equals 6.5 teaspoons of added sugar and over 11 teaspoons of simple carbohydrates that will soon break down to sugar in the body.

Runners were walking around with one of these energy bars in one hand and a banana or a bagel, or both, in the other hand. A large banana will break down to 6 teaspoons of sugar, and the average plain bagel will break down to 15.5 teaspoons of sugar in the body. Between the bagel, banana, and bar, these runners were eating the equivalent of almost 33 teaspoons of sugar. That is 5.5 ounces of sugar! And that was just one pre-marathon snack.

Now, don’t get me wrong. Those people were getting ready to run 26.2 miles in blazing hot temperatures. They needed to make sure they had fuel to run on. Eating sugar in larger amounts does have its place, i.e., before a marathon, but being a runner doesn’t give us a free ticket to eating all the sugar we want!

I believe education is the first key to making better choices. After reading through the rest of this article, you will be able to make a more informed decision when it comes to your nutrition and sugar consumption during training.

Sugar and Endurance

Research shows that when a runner consumes high-glycemic (Gl) foods, like white bread, ice cream, or high-sugar energy bars an hour before a run, he or she may become fatigued more quickly. In a recent issue of the Journal of Science and Medicine in Sports, researchers found athletes performed significantly faster 45 minutes after eating a low-Gl meal rather than a high-GI meal. A low-GI meal would be an apple with peanut butter or steel-cut oats. Consuming the high-Gl foods an hour before a run was causing athletes to experience a sugar crash, while the low-GI foods were carrying the runners farther and faster into the run.

Studies also suggest that exercising muscles can absorb a combination of fructose and glucose almost 40% faster than glucose alone. This is where most endurance nutrition companies claim their product is the best option for you before or during a run. But what most people don’t know is that whole foods, like fruit and oatmeal, contain a combination of glucose and fructose as well.

So, those Boston Marathoners could have mixed their banana with some peanut butter into dry oats for a longer lasting pre-race snack that would have helped them run both faster and longer with less fatigue!

Sugar and Health

Studies suggest that sugar activates the brain in a manner similar to narcotics. “More recently, a research study in France showed that intense sweetness—not just refined sugar, but also artificial sweeteners—surpasses cocaine….” YIKES!

The more you satisfy sugar cravings, the more likely you will be trying to run off a Buddha-belly. It is easy to stuff yourself silly on chocolate cake but not as easy with carrots.

The side effects of too much sugar don’t stop at your vanity pounds. A constant intake of sugar forces your pancreas to work overtime, possibly leading to type-2 diabetes down the road. It also lowers levels of HDL (good) cholesterol, while increasing triglycerides. Both increase the risk for heart disease.

The narcotic-like effect that sugar has on our bodies can also make tapering and rest days challenging. If you are watching your weight, you know that on tapering weeks and rest days, you don’t have as much freedom with food as you do on long run days.

The more sugar you eat on long run days, the more cravings you will have to fight on rest days.(Tweet this)

Set yourself up for success for tapering and rest days by getting your calories on long runs through whole, real foods.

Not All Sweeteners Are Equal

Calorically, all varieties of sweeteners are pretty much the same. Unlike most of other sweeteners, blackstrap molasses does offer some nutritional value for runners. Two teaspoons of blackstrap molasses can provide you with 13% of your daily iron, a nutrient that is easy for runners to be deficient in!

Aside from reducing your overall sugar/sweetener intake, the only other warning I want to throw out there is for agave.

Agave nectar has been touted as the best “healthy and natural” sweetener because it is sweeter than sugar or honey, so you can use less, reducing the calories you consume. There are two problems I see with agave syrup. First, it is not natural. Agave is extracted, filtered, heated, and hydrolyzed into agave syrup. Second, chemically, agave syrup is has more fructose than high fructose corn syrup. Companies use high fructose corn syrup in everything because it is sweeter that corn syrup and less can be used, making it cheaper to produce their products.

To Sum It Up

Sugar is sugar…is sugar…

When it comes to sugar, whether it is natural sugar, like molasses or honey, or processed sugar, like cane sugar or high fructose corn syrup, too much is harmful for your health and training.

I do believe energy bars have their place. For example, when it is three in the afternoon and you’re planning to head out for a 90-minute run at four, and you will need something to eat, an energy bar with lower sugar is perfect. It is quick, easy, and painless. Eating an energy bar just as a snack and not as a pre-exercise source of energy is not your best option.

Don’t use an energy bar to replace a healthier snack, like hummus and celery or an apple and peanut butter. (Click to tweet)

In today’s society, even runners, who need “sugar” to maintain energy on a run, have to watch what kind and how much sugar is in their diets. More and more runners are struggling with health issues, like hypertension and diabetes, due to the massive amounts of sugar they are consuming. Prepare and educate yourself and remember that running doesn’t make you invincible!

truth about sugar for runners


Barnes, Lisa. “The Truth about ”Natural” Sweeteners.” SparkPeople. Web. 23 Apr. 2012.
D. E. Thomas, J. R. Brotherhood, J. C. Brand. “Carbohydrate Feeding Before Exercise: Effect of Glycemic Index.” International Journal of Sports Medicine (2007): n.pag. Web. 23 Apr. 2012.
“Influence of Glucose and Fructose Ingestion on the Capacity for Long-term Exercise in Well-trained Men.” Clinical Physiology 4.6. – Bjorkman. Web. 23 Apr. 2012.
“Physical Craving and Food Addiction: A Scientific Review.” Food Addiction Institute. Web. 23 Apr. 2012.

Free Strength Training Course

The Right Way to Add Strength Training To Your Running to Avoid Injury and Improve Performance

Here’s what we’ve got for you

How the “core” actually contributes to your running and which muscle groups are most important for staying injury-free

Which type of strength training exercises are most likely to directly improve your running performance (based on scientific research)

The 5 most common mistakes runners make with strength training (and how you can fix them)


Connect with Jeff Gaudette on Google+

9 Responses on “The Truth about Sugar for Runners

  1. Great post! I agree that runners can completely overdue the sugar. I struggle with this, because my body is often craving the extra carbs/sugar after long runs. But I’ve learned the hard way not to fuel that way. Banana and pb is my go-to pre run fuel, or on a whole grain tortilla or bread for runs up to 13 miles. Thanks for the informative post!

    • Thanks Laura! Those are great go-to fuels! It is amazing how “sneaky” sugar can be! We often forget that vegetables are great pre/post run carbs too! Sometimes a sweet potato is that perfect amount of sweetness, but great source of carbs before a run!

      • Hi Abby,
        Your post is exactly what the doctor ordered. I am startled to read the first line. 22 teaspooons of sugar for bfast is unfathomable. Is that fact accurate? I am feeling guilty of adding 1 teaspoon (measuring spoon) of table white sugar in my morning coffee. and I sometimes go for the low fat vanilla flavored yoghurt after the gym 🙂 I hope to win my private and secret battles with sugar soon.

  2. Very good article. And what you have said is true: Running does not give us runners a licence to gobble up all sugar that we can. Natural sugar is a much better option for all of us than processed sugar. I can see from the table given in your article that most of the processed sugar looses the nutritional value.

  3. Pingback: Pour Some Sugar On Me… « Chasing 42

  4. Pingback: Is that six sugars or eight in your training cup? | signalyard

Leave a Reply

Your email address will not be published. Required fields are marked *

Adding new comments is only available for RunnersConnect Insider members.

Already a member? Login here

Want to become an Insider for free? Register here