Clean eating can help athletes perform better. But it’s not as easy as it sounds. Inexperience can often lead to mistakes, especially when foods claim to be healthy but in reality are not. Here are three food items that can deceive an unsuspecting athlete.

Trans Fat

It seems safe to assume that when a product label states “0 grams of trans fat,” it’s true. Yet it’s not a safe assumption, because it can mean that each serving contains a minimal amount (less than one gram) of trans fat, but if you eat more than one serving, the trans fat begins to add up. Read the list of ingredients. If it includes “hydrogenated oils” or “partially hydrogenated vegetable oil,” then the product contains trans fat. (See more Sneaky Food Label Tricks.)

Energy Bars

Energy bars were made especially for athletes, so they seem like a great snack option. The problem is that they often contain high fructose corn syrup, plus added sugar and saturated fats. Even “meal replacement” bars can contain too many extra calories. Read the label carefully to determine if an energy bar really qualifies for clean eating. (What a healthy bar looks like: How to Select a Healthy Protein Bar.)

Sports Drinks

Sports drinks play a vital role for athletes in competition. However, outside of activity, they provide little nutritional value due to their calories and added sugar, similar to sodas and energy drinks. Before, during and after activity, they are appropriate, but if you are not active, stick to a lower calorie sports drink, water, milk or green tea.