One of the ways I connect with my oldest son these days is through sports - and, in particular, Tennessee football.
It’s where I went to school, and where I was taught, then and there, how to bleed orange. And even though my boys were born and raised in St. Louis, they’ve adopted some of my love for the school and its sports, especially my oldest son.
So when there was SO much hype around the Tennessee–Texas rivalry: UT vs. UT (who is the real UT?!)…we were in.
The pregame show started at 8 a.m., and pretty much as soon as we came downstairs, we were glued to the TV.
But before the game even started, there was a story that caught my attention.
It was a segment about Tennessee’s strength and conditioning program and the remarkable changes players had made in speed, strength and body composition. The before-and-after numbers were impressive. More players were hitting certain speed benchmarks. Body-fat percentages had dropped. These were extraordinarily strong, lean, powerful-looking young men.
One piece of their transformation was mentioned several times:
The sports and conditioning coach had cut out all their sugar.
That’s where my sports-dietitian ear perked up.
Really? Was eliminating sugar the key to achieving these numbers?
As a sports dietitian, I suspected there was a much bigger story behind those results.
And while I understood the focus on performance, I couldn't help thinking about how that message might land with the young athletes watching at home.
But sitting there next to my son, I couldn’t help thinking about the message underneath the message.
Sugar is bad. Cutting it out is good. And if you want to be leaner, stronger, faster, more disciplined…this is what it takes.
Those weren’t the messages I wanted my son absorbing. And they certainly weren’t the messages I wanted young athletes carrying with them as they learned how to fuel and care for their bodies.
What does the science say about sugar and body composition?
There are plenty of good reasons to keep a diet relatively low in added sugar. Athletes, like the rest of us, need foods that bring along fiber, vitamins, minerals, protein and healthy fats. If sugary drinks, desserts and snack foods are taking up a large portion of someone’s diet, shifting toward more nutrient-dense foods makes sense.
But sugar doesn’t appear to have some unique ability to create body fat regardless of everything else someone is eating.
When researchers look at controlled studies, body weight tends to increase when sugar adds additional calories to what people are already eating. When researchers exchange sugar-containing foods for the same amount of calories from other foods, that effect largely disappears.
In other words, the story is considerably more complicated than:
Eat sugar → gain body fat.
And it becomes even more interesting when we’re talking about athletes.
Athletes need fuel
Carbohydrate is an important fuel source for training, particularly as exercise intensity increases.
That means the harder and longer athletes train, the more having enough carbohydrate available can matter.
Most of that carbohydrate should absolutely come from nourishing foods: fruit, grains, potatoes, beans, dairy and other foods that offer much more than carbohydrate alone.
But sometimes sports nutrition looks different from everyday nutrition.
During a long practice or game, a sports drink may be useful precisely because its sugar is quickly available and easy to digest. The same can be true of gels, chews and other sports foods.
The body isn’t assigning moral value to where that carbohydrate came from.
It’s using fuel.
The research on strength training adds an important bit of nuance. Someone who has eaten adequately and heads into a typical lifting session probably isn’t going to lift more simply because they drank something sugary beforehand.
But during longer or more demanding training—or when an athlete hasn’t eaten enough beforehand—having carbohydrate available can help support the amount and quality of work they’re able to do.
And over time, that matters. Because improvements in strength, muscle and body composition don’t come from eliminating a single nutrient. They come from consistently being able to train, recover and adapt.
But there's more to the story.
I would be surprised if the entire transformation we saw on television came from removing sugar. More likely, there were changes across the board: strength and conditioning, meal quality, protein, carbohydrate, recovery, sleep, overall energy intake and probably a whole lot of other things happening behind the scenes.
But television needs a headline.
“Cut out sugar” makes a pretty good one.
And there’s another number worth discussing: Body-fat percentages
I don’t know how Tennessee approaches body-composition testing with its athletes, but seeing those numbers featured so prominently in the segment brought up another question I’ve wrestled with throughout my career.
Body composition can matter in sport. Muscle mass can support performance, and in some sports, carrying additional body mass can affect speed and efficiency.
But there isn’t one particular body-fat percentage that defines athletic success.
Body composition can matter in sport. Muscle mass can support performance, and in some sports, carrying additional body mass can affect speed and efficiency.
But there isn’t one particular body-fat percentage that defines athletic success.
And there is another side to repeatedly measuring an athlete’s body.
Once we start giving athletes body-fat percentages, it’s remarkably easy for those numbers to become grades:
Lower is better.
Leaner means fitter.
Leaner means more disciplined.
Leaner means you’re doing it right.
That’s one reason sports-medicine guidance has become increasingly cautious about how body-composition testing is used, particularly with younger athletes. The question isn’t simply whether we can measure it, but why we’re measuring it, how that information will be used and what effect knowing the number might have on the athlete.
I remember this coming up for me years ago when I was interviewing with a professional sports organization and learned that players were having their body composition measured every month.
I remember wondering: What does knowing that number every month actually give the athlete?
And: What might it take away?
Because the question isn’t simply: Can we measure it?
It’s: What are we hoping this number will do for this athlete?
And maybe just as importantly: What might this number do to this athlete?
The message matters, too
We sometimes talk about sports nutrition as though the only outcome we’re trying to optimize is the body.
More muscle. Less fat. Faster. Stronger.
But an athlete also has a relationship with food and a relationship with their body.
And that matters.
When athletes begin believing that lighter is always better, or that certain foods need to disappear in order for them to be serious athletes, we can start moving toward underfueling, body dissatisfaction and disordered eating.
Ironically, eating too little can eventually undermine many of the things athletes were trying to improve in the first place: strength, endurance, recovery, concentration and the ability to consistently train.
And this isn’t a reason to never talk about nutrition or body composition.
It’s a reason to remember that how we talk about these things matters.
What are we teaching our young athletes?
My son wasn’t watching that segment with the eyes of a sports dietitian. He was watching college athletes he admired, young men who had made impressive gains in strength, speed, and body composition.
And I think about the influence these athletes have on boys like mine. They represent so much of what young athletes aspire to become: strong, disciplined, competitive, successful. When they talk about how they train, what they eat, and what they avoid, kids are listening.
And amid all those impressive gains, one message was particularly easy to remember:
They cut out sugar.
I don’t know everything that happened inside Tennessee’s football program. Nutrition professionals are part of the larger performance team, and I would imagine the actual nutrition strategy is far more nuanced than the few minutes we saw on television.
But that nuance doesn’t always make it into the headline. And when the message comes from athletes our kids admire, it’s worth considering not just what was said, but what they might have heard.
But that’s precisely the problem with simple nutrition messages.
The nuance stays behind the scenes.
The teenager watching at home gets the rule.
And perhaps what I want my son, and every young athlete sitting on a couch watching those bodies, to know is this:
Sometimes fear and rigidity around food can masquerade as discipline. But they aren’t requirements for athletic success.
Strong athletes need enough fuel.
They need protein and plants and carbohydrates and fats. They need sleep and recovery and good coaching. They can eat mostly nourishing foods and still have foods simply because they enjoy them.
And their body-fat percentage isn’t a grade.
Maybe that’s the part of the before-and-after story we need to start showing, too.
Research & Further Reading
For those of you who like to dig into the sports-nutrition science, here are some of the research and consensus papers behind this piece:
Mountjoy M, Ackerman KE, Bailey DM, et al. 2023 International Olympic Committee’s (IOC) consensus statement on Relative Energy Deficiency in Sport (REDs). British Journal of Sports Medicine. 2023;57:1073–1097.
https://bjsm.bmj.com/content/57/17/1073
This is the IOC’s updated REDs consensus statement, including guidance around low energy availability, athlete health, psychological factors and body-composition assessment.
Mathisen TF, Ackland T, Burke LM, et al. Best practice recommendations for body composition considerations in sport to reduce health and performance risks: a critical review, original survey and expert opinion by a subgroup of the IOC consensus on Relative Energy Deficiency in Sport (REDs). British Journal of Sports Medicine. 2023;57:1148–1160.
https://bjsm.bmj.com/content/57/17/1148
This is the particularly relevant paper on body-composition assessment. It discusses the limited evidence for sport-specific “ideal” body-composition targets, recommends against routine body-composition assessment in athletes under 18, and suggests that more than four to six assessments per year is likely unnecessary even when assessment is appropriate.
Chiavaroli L, Lee D, Ahmed A, et al. Effect of fructose-containing sugars on adiposity: a systematic review and meta-analysis of controlled feeding trials. American Journal of Clinical Nutrition. 2023.
A large review of 169 controlled feeding trials examining sugars and measures of body fat. The findings help separate the effects of sugar itself from the effects of consuming additional energy.
Henselmans M, Bjørnsen T, Hedderman R, Vårvik FT. The effect of carbohydrate intake on strength and resistance training performance: a systematic review. Nutrients. 2022;14(4):856.
A useful review for understanding when additional carbohydrate does—and doesn’t—appear to improve strength-training performance. Carbohydrate becomes particularly relevant with longer, higher-volume training and when athletes begin training without adequate fuel.
Kerksick CM, Wilborn CD, Roberts MD, et al. ISSN exercise & sports nutrition review update: research & recommendations. Journal of the International Society of Sports Nutrition. 2018;15:38.
A broader sports-nutrition reference covering energy needs, carbohydrate, protein, nutrient timing and recovery.
Menu for the Week of October 12-16th
Monday: Veggie-Packed White Bean Minestrone
Tuesday: Ground Turkey Tacos
Wednesday: Plum Salad with Arugula & Blue Cheese
Thursday: Yummy Salad Burgers with Slaw
Friday: Greek Yogurt Lemon Bars
Monday: Veggie Packed White Bean Minestrone
Tuesday: Ground Turkey Tacos
Wednesday: Plum Salad with Arugula & Blue Cheese
Thursday: Yummy Salmon Burgers with Slaw
Friday: Greek Yogurt Lemon Bars
Enjoy the joy of eating,
XO Jen
Wonderful article! Well balanced and informative! Thank you!