Common Nutrition Mistakes Athletes Make
As a sports dietitian, I see a lot of the same nutrition mistakes show up across sports, levels, and seasons. Most of the time, these mistakes aren’t because athletes don’t care or aren’t disciplined enough—they’re usually the result of confusing, oversimplified, or flat-out bad nutrition advice.
If you’ve ever felt overwhelmed by what you’re “supposed” to eat as an athlete, you’re not alone. Let’s break down some of the most common nutrition mistakes I see and talk about what actually supports performance.
Cutting out foods
You might have been told that you should cut carbs, candy, or “junk food” for your performance or health. I see this backfire time and time again. When we focus on what we can’t have, that often makes those foods more interesting and harder to avoid.
It’s like telling you not to think about a pink elephant. It’s a surefire way to think about a pink elephant.
Instead of focusing on restriction, it’s often much more helpful to think about what you could add to support your performance. Can you make snacks a little more balanced? Are you including multiple food groups at meals? Are you eating often enough to support your training?
All foods can fit (especially foods that you enjoy) but athletes do need to be smart about when certain foods are eaten. For example, fuel timing around practices and games matters a lot more than whether a food is considered “good” or “bad.”
When athletes overly restrict foods, I often see:
Low energy in training
Increased cravings later in the day or week
Inconsistent fueling that hurts recovery
Performance nutrition works best when it’s flexible, not rigid.
Getting nutrition information from random sources (or copying what someone else is doing)
Everybody eats, but that doesn’t make them an expert on nutrition. That’s like saying because your neighbor pulled out a splinter, they should be trusted to do surgery!
There are plenty of people online who say a certain way of eating “worked for them.” And while that might be true for their body, schedule, and training load, it doesn’t mean it will work for you. I can promise you—after working with hundreds of athletes—that there is no one way of eating that works for everyone.
Nutrition needs vary based on:
Body size and composition
Position or event
Training volume and intensity
Injury history
Schedule, access to food, and stress
There is often a lot of trial and error involved in finding an approach that actually works for you.
There are credible sports nutrition resources out there. A few I regularly recommend include:
There are also a lot of opinions out there—and not all opinions are accurate, useful, or appropriate to apply to yourself. Be critical about where you get your nutrition information.
It’s also important to know that dietitians are licensed health professionals, whereas the term “nutritionist” is not regulated or licensed. There is an additional board certification called the CSSD (Certified Specialist in Sports Dietetics) that demonstrates advanced expertise in sports nutrition. If possible, I recommend working with someone who has both the RD and CSSD credentials.
Thinking nutrition needs to be strict and disciplined
Yes, you are an athlete—but you are also a human.
There are many reasons we eat beyond performance: celebration, connection, culture, and enjoyment. Joy is an essential nutrient, and food is supposed to taste good.
Balance matters far more than trying to do everything perfectly. Many athletes also have high energy needs and busy, on-the-go schedules. That makes convenience, prepared, or processed foods not just acceptable, but often a very practical option.
The most important thing for athletes is that they are getting enough food to keep their bodies functioning, recovering, and adapting to training. Overly rigid nutrition rules can actually make this harder, not easier.
Even athletes at the highest level fuel their bodies with foods they enjoy, alongside foods that provide essential nutrients. Sustainable nutrition beats “perfect” nutrition every time.
Taking supplements because that’s what the pros do
While supplements can be necessary in certain situations, like correcting a nutrient deficiency under the guidance of a medical professional, they are not a catch-all solution for performance.
I often see athletes missing the biggest needle movers:
Sleeping ~8 hours per night
Eating 5–6 times per day
Staying adequately hydrated
…and taking multiple supplements.
Supplements like creatine can’t replace training, recovery, or consistent fueling. Creatine might help you eke out a few extra reps, but the majority of your quality training reps come from adequate fuel, hydration, and smart programming. Maxing out once doesn’t make you stronger. Showing up and repeating quality sessions over and over make you stronger and 99% of that is proper fuel and recovery.
Think of supplements like sprinkles on an ice cream sundae. They’re a nice touch and they look fancy, but it’s what’s underneath them that actually makes the dish.
If supplements are being considered, it’s important to proceed with caution. Many products are not third-party tested, which means:
The manufacturing process could lead to contamination
The product may not contain the ingredients (or amounts) listed on the label
Look for supplements that are USP verified, NSF Certified for Sport, or Informed Sport certified. USP testing checks batches for purity and accuracy, while NSF and Informed Sport specifically screen for banned substances and label accuracy. These products tend to be more expensive, which is another reason to make sure the basics are dialed in first.
The big picture
Most performance gains don’t come from extremes, restriction, or supplements. They come from consistently doing the basics well: eating enough consistently, staying hydrated, sleeping, and choosing nutrition strategies that actually fit your life.
You don’t need perfect nutrition to perform well. You need adequate, flexible, and sustainable nutrition that supports both your body and your humanity.
If you want help sorting through what that looks like for you, working with a sports dietitian can make a huge difference.
