Home » team of experts » Nancy Clark » Everyday Sports Nutrition » Should Athletes Avoid Junk Food?

Should Athletes Avoid Junk Food?


“I'm training really hard, doing double workouts, and eating only healthy foods. I feel full all the time—but I am losing too much weight. I don't think I could comfortably eat any more…”


“I generally eat clean—but some days I cheat and have ice cream.”


“Fruit juice is bad; it has way too much sugar! I’ve stopped drinking it.”

As these quotes from some of my clients demonstrate, many athletes go to great extremes to eat healthfully.

Needless to say, the definition of “eating healthfully” varies from person to person—and often takes on a religious zeal, but “healthy eating” tends to include a lot of "no's":

  • No refined sugar, gummy candy, soda pop, sweets
  • No potato chips, corn chips, Cheetos, salty snacks
  • No doughnuts, pastries, croissants, pancakes, PopTarts
    Pepperoni pizza
  • No McDonald's, Burger King, pizza, hot dogs 
  • No cookies, desserts, birthday cake, holiday treats.
  • No foods in wrappers—particularly among athletes who are “eating clean.” (Question: Are wrapped foods actually dirty? Or is trendy terminology breeding craziness?)
While eliminating “bad” and “dirty” foods is a noble attempt to put premium nutrition into your body's engine, questions arise: 
  1. Do you really need to eat a “perfect diet” to have an “excellent diet”? No
  2. Does enjoying a hot dog or a candy bar once in a blue moon negate all of the “good stuff” you generally eat? No
  3. Do have to “cheat” on your birthday so you can partake in cake with your family and friends? Heavens no!!!

No such thing as "bad food"

In my opinion, there is no such thing as a “bad food.” There is a bad diet, yes, as judged by looking at the whole day’s intake. That is, 50 calories from refined sugar in 8 ounces of a sports drink will not ruin your health. But consuming 400 calories from a half-gallon of sports drink displaces a significant number of nutrient-dense food, and sipping all day on sugary, acidic fluids can ruin your teeth by damaging tooth enamel.

While foods with little nutritional value fail to invest in an athlete’s well-being and ability to withstand the demands of rigorous training, occasional “junk food” does not ruin health when eaten in moderation. You can indeed have an excellent diet without having a perfect diet. 

How much “junk food” is OK to eat? 

A healthful sports diet can target 85 to 90-percent of calories from quality foods and 10 to 15-percent from “whatever.” Some days “whatever” might be blueberries and other days it might be (guilt-free) blueberry pie with ice cream. Given that you can ingest the recommended intake of all the vitamins, minerals, and protein you need within 1,500 calories from a variety of wholesome foods, a hungry athlete who consumes 2,000 to 4,000 calories a day has the opportunity to consume LOTS of nutrients. For example, 8 ounces of orange juice offers 100% of the Recommended Dietary Allowance (RDA) for Vitamin C. A thirsty runner who chugs the whole quart can consume 4 times the RDA in that one snack. OJ is better than an all-natural vitamin pill! 

But isn’t fruit juice filled with sugar? 

Yes, all the calories in juice come from natural sugar. This sugar fuels muscles. Vitamin C, potassium, folate, and a multitude of health-protective, anti-inflammatory bio-active compounds also come in the juice. For athletes who want to eat “healthy” but have trouble getting in enough calories to maintain weight, I often recommend grape, pomegranate, tart cherry, orange, and blueberry juices. (In contrast, overfat people who reduce their juice intake can easily delete some calories. For them, eating the whole fruit would be more satiating.)  

Should athletes try to avoid refined sugar? 

Refined white sugar is a nutritional zero, void of any vitamins, minerals or protein. Yet, the calories in sugar come from carbohydrates. Muscles welcome these carbs to fuel depleted glycogen stores. Muscles don’t know the difference between carbs from juice, candy, and sports drinks vs. apple, sweet potato, and banana. The difference shows up in health, immune response, and ability to fight off colds and flu. 

A good rule of thumb is to limit refined sugar to 10% of total calories. For most active women, that equates to 200 to 250+ calories from sugar a day. And for active men, 250 to 300+ calories. That means, an athlete could enjoy either 16-ounces of a sports drink and a gel or a few cookies—and stay within the recommended sugar-budget for the day. 

Note: The "sugar is evil" message is targeted to the 66% of Americans who are over-fat and under-fit, not to athletes. The muscles of athletes easily take up sugar from the bloodstream with far less insulin than needed by unfit people. Hence, unfit people who sip on Big Slurpees all day easily consume excessive, health-erosive sugar-calories. They need to seriously think about their future and if they want to be vibrant and healthy enough to enjoy fun times. 

Can you eat too healthfully? 

Yes. Eating too many healthy foods can actually be bad for you. For example, fruits & veggies are healthy foods, but eating only fruits & veggies creates a bad diet. Eliminating all unhealthy foods is also needless. Enjoying birthday cake can be good for the soul! 

Rather than categorize a food as being “bad,” please look at your whole diet to see if it is balanced. I differentiate between a diet filled with PopTarts for breakfast, Fluffer-nutters for lunch, candy bars for snacks, and sweet & sour chicken for dinner vs. the occasional PopTart tossed into a gym bag for a pre-exercise energy booster when traveling to an event. While not trendy, choosing a balanced sports diet based on moderate portions offers a sustainable, effective path that can help you eat well, perform well, and feel great. 

Nancy Clark, MS, RD is a longtime member of MomsTEAM's Team of Experts. She counsels active people at her private practice in Newton, MA (617-795-1875). Her Sports Nutrition Guidebook and food guides for marathoners, soccer players, and cyclists offer abundant tips to help you balance your sports diet. The books are available at www.nancyclarkrd.com. For online education, visit www.NutritionSportsExerciseCEUs.com.