High-Fructose Corn Syrup
Gummy worms and other sweet pick-me-ups may seem to provide a quick energy burst, but they're really just loaded with sugar and empty calories, offering zero nutritional value. "If you eat really sugary foods before your workout, you can get 'rebound hypoglycemia,' otherwise known as a sugar crash, during your workout," Dr. Metzl explains.
Another reason to resist the urge to splurge on sugary stuff? Sweet treats, whether they contain high-fructose corn syrup, real sugar, or artificial sweeteners, could also make you "skinny fat," promoting dangerous fat buildup around your organs! (Here's why you should ditch artificial sweeteners once and for all.)
TRY THIS INSTEAD: Fruits, vegetables, and anything else from nature. Dr. Metzl's rule of thumb? "If it doesn't expire until 2026, don't eat it," he says.
Related: 14 Foods These Health Experts Will Never, Ever Eat
Pre-Workout Dairy and Fried Foods
These types of foods take a long time to digest, so avoid eating dairy and fried foods right before your workout or run so your gut has time to break everything down—that takes a lot of energy!
TRY THIS INSTEAD: An apple or other simple, one-ingredient snack from nature.
Forget fried chicken and eat lean roasted chicken instead. Here's the simplest roast chicken recipe ever:
Metabolic Efficiency Training Specialist Nicci Schock, founder of Elevate by Nicci, says her philosophy and training with nutrition are based on blood sugar and insulin management and metabolic efficiency. She recommends avoiding the following foods:
Yogurt is made from milk (lactose), and lactose breaks down into sugars, Schock explains. "Depending on the brand you choose and how it was processed, you're often consuming an unbalanced portion of carbohydrates, which will lead to blood sugar instability," she says. "Keeping your blood sugar stable is one of the foundations of health."
TRY THIS INSTEAD: Schock recommends that her athletes choose a full-fat Greek yogurt to ensure the right balance of macronutrients, which helps athletes feel full longer, and keeps their bodies in tune with biological hunger patterns.
Related: 10 High-Fat Foods You Should Be Eating More Of, According To Nutritionists
Sports-Nutrition Drinks, Gels, and Bars
Most sports-nutrition products on the market are high in sugars with no nutritional benefit. Since many athletes don't know how to properly modify their overall nutrition plan to incorporate these sports-nutrition products in a healthy way, many eat and drink too much, and in many instances, actually gain weight. (Here are 10 gross ingredients lurking in your energy bars.)
TRY THIS INSTEAD: Get the same energy boost from whole food sources like nuts and seeds, Schock says.
"Cereal is one of the worst breakfasts a person can eat," Schock says. Based on the serving size that fits in most bowls, you could be eating the equivalent of four to five slices of white bread, and that's before you add any liquid to the bowl.
TRY THIS INSTEAD: Start the day with whole eggs, green vegetables, and a slice of sprouted-grain bread spread with avocado.
Related: I Ate 3 Eggs Every Single Morning For A Week—Here's What I Learned
Brendan Brazier, a bestselling author and developer of Vega health foods, often talks about the concept of "crowding out," which essentially coaches people to crowd out the bad-for-you foods by adding in the good ones. The idea is that eventually, the good foods will crowd out the bad. Since Brazier's a plant-based athlete, he says these are some obvious food choices he would coach people away from:
Whey Protein and Other Animal-Based Protein Powders
It was once thought that only animal protein was complete and therefore superior to plant-based options. Complete protein is comprised of all 10 essential amino acids. By definition, essential amino acids cannot be made by the body; they must be obtained through dietary sources. But, in fact, there are actually several complete plant protein sources," Brazier says.
"What's more is that animal-based food is highly-acid forming, which wreaks havoc on the body," Brazier notes. "Eating too many acid-forming foods will promote inflammation, reduce immune function, and cause highly alkaline calcium to be pulled from the bones to keep the blood in its neutral state."
This, of course, leads to lower bone density and in many cases, osteoporosis. Brazier says whey protein isolate, for example, is highly acid forming. Whey, straight from the cow, would be neutral and even slightly alkaline, but once the protein gets isolated (therefore rendering it no longer a whole food) and is then pasteurized, these two steps of processing lower its pH, making it considerably more acid-forming. In contrast, plant-based protein is only slightly acidic or neutral pH.
"Plant-based proteins also tend to have high-net-gain nutrition, which essentially means more nutrients per calorie, needing much less energy to digest and assimilate, but giving you more nutrients in return," Brazier says. "The less energy you spend digesting your food, the more energy you’ll have to use as fuel, thus enhancing your performance."
Related: Here Are 7 Sketchy Ingredients Lurking In Your Protein Powder
TRY THIS INSTEAD: Additionally, plant-based proteins don't cause inflammation. When inflammation goes down, muscle functionality goes up, which means you can move more efficiently which means you don't have to spend as much energy moving. "If you're an athlete—that's huge," Brazier says. So swap out your animal-based protein powders for lentils, legumes, beans, peas, nuts, seeds, and greens. Instead of whey, try a Vega Protein Smoothie, a high-quality, plant-based protein, to fuel your active lifestyle.
There is a lot of advice out there that suggests drinking coffee before a workout will help increase energy and focus, among other things. And it's true that coffee and other caffeine-containing foods and beverages stimulate the adrenal glands, creating energy. "But unfortunately, this energy doesn't last long," Brazier notes. "Adrenal stimulation results in quick yet fleeting energy that is always followed by fatigue. If this cycle of adrenal fatigue is allowed to continue and become part of a regular part of life—as it does for most of the North American population—compounded adrenal exhaustion ensues.
TRY THIS INSTEAD: Brazier recommends drinking green tea before a workout. While green tea leaves do contain a form of caffeine, it differs significantly from the form found in coffee beans, he says. "Theophylline causes a slow, steady release of energy over the course of several hours," Brazier says. "Therefore, it does not cause caffeine jitters and places less stress on the adrenal glands."
Green tea is also rich in chlorophyll and antioxidants. Drinking it before exercise can improve the level of intensity a person can reach during a workout or on race day, which can lead to better, faster results, Brazier notes. Theophylline has also been shown to help improve focus and concentration, calming nerves.
Related: I Drank Match Tea Instead of Coffee Every Morning For A Week And Here's What Happened
Refined, Processed Complex Carbs
(Think pasta, wheat flour, and potatoes.) While complex carbohydrates release energy at a slower rate than simple carbohydrates—and therefore will not cause a sharp blood sugar crash—they have a commonly overlooked fault, Brazier says.
"What complex carbohydrates make up for in sustained energy release, they lose in digestibility and efficient transfer from food into energy," he explains. "In addition, refined, processed complex carbohydrates, such as those found in regular pasta and white bread, cause inflammation." Having an exceptionally low pH, and a significant acid-forming attribute, refined foods will promote inflammation and therefore reduce performance by hampering efficiency.
TRY THIS INSTEAD: In contrast, carbohydrates in raw fruit and sprouted buckwheat, for example, help reduce inflammation, leading to quicker recovery from exercise, better joint mobility, and thus improved endurance. Also try amaranth, quinoa, wild rice, hemp, chia and flax.