Runners are often on the lookout for foods or food substances that could sabotage their training efforts.

Sugar, while metabolically helpful during long or hard training efforts, is quick to get the boot. Reducing or eliminating sugar is a relatively common practice among runners and health enthusiasts, for various reasons. In this case, these are extraneous sugars—those from “junk” foods and sweets. Natural sugars, found in grains, fruits and vegetables, often get a pass.

You may hear descriptors such as “processed” or “added sugars” in reference to these elimination efforts. The 2015 Dietary Guidelines categorizes the following as added sugars: cane sugar (e.g. white or brown) and caloric sweeteners (e.g. honey, brown rice or maple syrup). These are sometimes called simple sugars, which refers to their chemical makeup. Other processed sugars include artificial sweeteners and sugar alcohols. Even though they are calorie-free, research has linked consumption of artificial sweeteners to an increased risk of developing type 2 diabetes and metabolic syndrome.

Why might a runner consider reducing added and processed sugar intake?

Simply put, “Reducing simple sugars will improve health,” says registered dietitian Jonathan Valdez, owner of New York City-based Genki Nutrition. According to statistics provided by the Centers for Disease Control (CDC), the average percentage of total calories from added sugars decreased from 2005-2010 among American adults. Even so, more of these sugars come from foods than beverages. An excessive sugar intake has been associated with adverse health conditions, according the American Heart Association’s 2009 Scientific Statement on dietary sugars. This may include increased triglyceride levels, a risk factor for heart disease, and insulin resistance that may lead to type 2 diabetes.

Chronic health risks noted, there may be both daily and training benefits to reducing added and processed sugar intake. “For avid runners it can prevent possible reactive hypoglycemia (low blood sugar levels) or sugar crashes during long runs,” Valdez says.  

Additionally, most sugars contribute calories without providing any essential nutrients or fiber (which we do get with natural sugars like fruits and vegetables). Added sugars may cause spikes in blood sugar levels, and consequently, as Valdez mentioned, energy crashes. In other words, added sugars contribute to our daily energy intake without offering any nutritional benefit. If simple sugars are replaced with something healthier, such as fruits or whole grains, you’ll naturally eat more vitamins, minerals, antioxidants, and fiber. This, Valdez adds, “is more beneficial for helping a body recover from exercise stress.”

How can runners reduce daily added and processed sugar intake?

The 2015 Dietary Guidelines provide a recommended daily limit for added sugars, no more than 10 percent of your daily caloric intake. “While it isn’t realistic, or mentally healthy, to completely cut out processed sugars, reducing your intake at meals and snacks can aid your appetite control,” advises Philadelphia-based sports dietitian Kelly Jones. Sticking to the recommended intake allows flexibility to not only enjoy your preferred sweets and treats while training, but also to keep sport gels and snacks as part of your endurance fueling arsenal.

If you want or need to reduce daily added sugars, the first step is to distinguish between your sources of natural and added sugars. Separate fruits, vegetables, dairy products (unless flavored), and whole grains—which provide natural sugars and fibers—from baked goods, sport products (snacks and drinks), and packaged snacks. Identifying packaged sources of added sugars may be easier in the near future, when the FDA sets a compliance date for proposed Nutrition Facts Label changes. (Originally these were set to be in place by July 2018.) Added sugars will be listed beneath “Total Sugars,” in the “Total Carbohydrates” category. For now, checking the required ingredient list for added sugars and caloric sweeteners is helpful in efforts to reduce intake. Though, even that can be tricky, as there are up to 50 sources of added sugars in processed foods.

In lieu of a medical condition, such as diabetes, it’s probably not necessary to spend mental energy tallying up what percentage of your intake is made up of added sugars every single day. Rather, be mindful of added sugar sources in your diet and balance those out with natural sugars like fruits, vegetables, dairy products, and whole grains.

Some general tips for reducing added sugar intake:

  • – Opt for fresh fruits, or dried fruits without added sugars
  • – Make your own trail mixes with dried fruits and raw or salted nuts
  • – Choose plain whole grain options (e.g. plain oatmeal instead of flavored)
  • – Check ingredient lists for added sugars in your staple snacks
  • – Try dark chocolate instead of milk chocolate
  • – Reserve gummies, gels, and other sugar-based candies for fueling on the run
  • – Sweeten smoothies, oatmeal, or yogurt bowls with frozen or fresh fruits
  • – Drink unsweetened beverages (e.g. water, tea, coffee, sparkling water) more often than sports drinks

Still, there are times when sugar is beneficial to the runner’s diet.

Whether processed or natural, sugars are still our body’s primary source of fuel, especially during exercise. “Sugar is not only helpful, but necessary to take in during endurance exercise that lasts over an hour,” Jones notes. If your goal is to run and endurance event like a half or full marathon, Jones recommends fueling the muscles with sugar-based foods (natural or otherwise) to maintain normal blood sugar during exercise to prevent fatigue. There’s a time and place for these sweet sport-specific foods and drinks. Just don’t let them become your go-to sources of fuel and hydration every day.