Mistakes Vegetarian and Vegan Athletes Should Avoid

Plant-Based Diets and Athletic Performance

Vegetarian and vegan questionnaire
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Vegetarian and vegan diets are rising in popularity and athletes are taking notice. There is enough evidence to support plant-based diets providing numerous health benefits, but research is lacking for athletic performance. On top of that, eating this way remains questionable because of food myths and discussions focusing more on how to avoid nutrient deficiencies rather than the benefits of eating whole foods.

However, according to the American Dietetic Association (ADA), vegetarian diets can be nutritionally sound and adequate for all, including athletes.

Benefits of Plant Diets

Studies indicate plant-based diets provide numerous health benefits, including:

  • Reduced risk of heart disease
  • Lower low-density lipoprotein (LDL) cholesterol levels
  • Lower blood pressure
  • Lower rates of type 2 diabetes
  • Lower body mass index
  • Lower insulin resistance
  • Lower rates of cancers

Despite the positive health benefits, many active individuals and athletes accept rumors about veganism without even knowing what it means to eat vegetarian or vegan. Before exploring the common myths and mistakes among vegetarian and vegan athletes, understanding the following definitions will be helpful:

  • Vegetarian — Eats no animal flesh, but may consume eggs and dairy.
  • Vegan — Does not consume any food of animal origin. 
  • Flexitarian — Regularly follows a vegan diet, but occasionally consumes dairy, meat, fowl, or fish.
  • Nutritarian — Follows a nutrition plan high in micronutrients, based on unrefined plant foods including vegetables, fruits, nuts, seeds, and beans (may or may not be vegan).

Although an optimal diet for the vegan athlete has yet to be defined, Dr. Joel Fuhrman, nutritional medicine expert for over 25 years, suggests vegan athletes who follow a nutritarian diet will have a performance advantage. His article published in Current Sports Medicine Reports suggests vegan athletes can effectively perform at high endurance levels while consuming a diet focused on micronutrient-rich whole plant foods.

Several high-profile vegan athletes, including Olympian Carl Lewis, Ironman triathlete Brendan Brazier, and tennis champion Venus Williams, have demonstrated superior athletic performance without consuming animal products. The performance of these well-known vegan athletes is remarkable but it’s only anecdotal evidence of athletic success. More research is required to dispel the common myths surrounding vegetarian (vegan) diets for athletes.

Common Myths and Mistakes

Athletes seem to have assumptions about vegetarian and vegan diets. The most common myths surround protein intake, plant proteins needing to be paired to create complete proteins, and sugar intake. It appears the following belief systems continue to be problematic for vegetarian (vegan) athletes:

  • Fear that plant foods are unable to supply enough protein.
  • Need to pair vegetarian proteins.
  • Focus on only protein rather than a balanced diet full of phytonutrients and antioxidants.
  • Think all sugars are the same.
  • Think juice is always a no-no.

Getting Adequate Protein From Plants

Athletes require additional protein to support extreme physical demands and repair muscle protein breakdown caused by intense workouts. Adequate protein intake is essential to this process. Insufficient protein consumption can lead to a negative nitrogen balance and insufficient muscle recovery.

Plant-based diets can supply enough protein for athletes according to Nancy Clark, internationally known sports nutritionist, counselor, and author of The Sports Nutrition Guidebook. Many vegetarians and vegans are excellent athletes but that doesn’t mean they’re getting enough protein, says Clark. The problem is many athletes simply don’t eat enough. For example, it’s not uncommon for female, weight-conscious athletes not to get enough protein due to consuming too small of portions per meal.

What also remains a point of confusion and disagreement among athletes and the scientific community is how much protein should be consumed for optimal body functioning. Whether the protein comes from animal or plant source, consuming the right amount and amino acid profile is said to determine how well your body is able to recover from high levels of physical exercise. Studies indicate protein requirements can be easily met for athletes who consume meat and vegan athletes using proper dietary planning.

The Academy of Nutrition and Dietetics recommend vegetarians and vegans consume a wide variety of plant-based foods to meet their protein and amino acid requirements.

Meat is a good source of protein, but plants contain protein as well. There are about seven grams of protein per ounce of meat and one ounce of pistachios contains six grams of protein. If the athlete is vegetarian, then milk, yogurt, and cheese can add additional sources of protein. For the vegan athlete, beans can add the needed protein, says Anding.

The Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine recommend 1.2 to 2.0 grams of protein per kilogram of body weight per day for athletes, depending on training.

Consuming protein in excess of 2.0 g/kg/day has shown no benefit in several studies and may even cause adverse health effects. Excessive protein intake can negatively affect calcium stores, kidney function, bone health, and cardiovascular functioning.

Combining Plant Proteins

Remember how it was important to eat beans and rice together at one point? The once popular recommendation to combine plant proteins to achieve a complete essential amino acid profile is no longer considered necessary. Current research suggests vegetarian or vegan athletes can get enough protein when eating a variety of plant foods over the course of the day, rather than a single meal.

Consuming a variety of plant proteins daily provides differing amino acids and ensures all amino acids are included, according to sports nutritionist Nancy Clark. It’s not necessary to pair the proteins at the specific meals. The goal is to have 15 to 20 grams of protein per meal to supply the correct amount of protein per day, says Clark.

Plant foods including grains, legumes, nuts, and seeds are recommended for the vegan diet and ensure essential amino acids (EAAs) and branch chained amino acids (BCAAs) are available for optimal body function and muscle recovery. Excellent sources of quality plant protein can be found in the following whole foods:

  • Lentils
  • Quinoa
  • Tofu
  • Black beans
  • Pumpkin seeds
  • Almonds
  • Oats

Protein Intake vs. Balanced Diet

Many vegetarian or vegan athletes believe they need to focus on consuming more protein to meet daily requirements. Protein intake is essential but consuming all macronutrients including carbohydrates and healthy fats are just as important for athletic performance. The problem for many of these athletes is not considering the role of carbohydrates in muscle function, growth, and recovery.

According to sports nutritionist Nancy Clark, many athletes are working out but only consuming a protein drink. These drinks lack the necessary glucose and other nutrients coming from carbohydrates to properly refuel their muscles. Eating a balanced diet pre and post workout satisfies macronutrient requirements for optimal athletic performance.

Consuming a wide variety of plant foods not only provides protein, but also the energy to complete intense workouts. Eating a plant-based diet also supplies the body with essential phytonutrients and antioxidants necessary for working muscles. Foods high in phytonutrients and antioxidants may reduce the effects of excess inflammation and promote recovery from physical training.

The following green vegetables are high in protein, micronutrients, and antioxidants: 

  • Kale
  • Bok choy
  • Broccoli
  • Collards

The following fruits are high in antioxidants:

Sugar Is Sugar

Most vegetarian and vegan athletes stay away from sugar mostly because of the refining process. Refined sugar is bleached using bone char filters. The sugar doesn’t actually contain bone particles, but the sugar has come in contact with the sterilized animal bone. Not all sugar is processed this way so really can’t be considered the same. There are sugars considered acceptable in a plant-based diet. However, keeping sugar intake to a minimum is still recommended for general health.

Athletes require more sugar compared to the average American according to sports nutritionist Nancy Clark. Sugar is the gas in the car and required to refuel working muscles. Post recovery drinks like chocolate milk contain sugar but also essential vitamins and minerals essential for optimal body function and athletic performance.

Refined sugar is certainly less healthy than beet sugar or agave nectar but the body reads sugar as sugar. All sugar contains 4 calories per gram and is a subcategory of carbohydrates. There are five different sugar types:

  • Glucose — Simple sugar also called dextrose and commonly referred to as blood sugar. 
  • Fructose — Simple sugar also called fruit sugar quickly absorbed by the body.
  • Galactose — Simple sugar found in milk and yogurt slowly absorbed by the body.
  • Maltose — Simple sugar also called malt sugar quickly absorbed by the body.
  • Lactose — Also called milk sugar and contains glucose and galactose. 

Sugar is the primary energy source used during exercise. The following sugars are considered acceptable for vegetarian/vegan diets:

  • Agave
  • Brown rice syrup
  • Maple syrup
  • Date syrup
  • Molasses
  • Stevia
  • Beet sugar
  • Coconut sugar
  • Honey (debated sugar)

Endurance athletes, especially, benefit from consuming more sugar in order to support increased glucose uptake into the muscle cells. Without adequate sugar (energy) to fuel your muscles, you won't perform as well when exercising.

Should I Avoid Drinking Juice?

Athletes, in general, assume juice is nothing but sugar and shouldn’t be included in a healthy diet. Juice concentrates contain natural fruit juice mixed with lots of water compared to sugar-added juice cocktails. It’s the type of juice being purchased that can be problematic. Pure juice from concentrate is routinely recommended by sports nutritionists and registered dietitians to help high-endurance athletes meet daily caloric requirements.

Many athletes struggle with weight loss because of the physical demands of their sport. Adding a glass or two of 100 percent juice instead of water daily has helped these athletes gain and maintain an appropriate weight. Sometimes food just isn’t enough and juice provides that additional boost for athletes who need lots of calories to meet physical demands. Athletes who may benefit from adding juice to their nutrition programs include high school athletes, long-distance runners, triathletes, and cyclists.

More Research

Research has shown plant foods beneficial to improve health and reduce disease risk factors, but little evidence exists showing the effects of these diets on athletic performance. Because vegetarian, vegan, and combination plant-based diets are being adopted by athletes, more studies are starting to surface.

A small study published in the Journal of Nutrients measured cardiorespiratory fitness between vegetarian and omnivore (meat-eating) endurance athletes. Results indicated vegetarian athletes had higher oxygen uptake values and equivalent strength compared to meat-eating athletes.

Other research conducted by Baylor University Medical Center followed the dietary intake of a female vegan cyclist during an 8-day mountain bike stage race. The athlete consumed over the recommended carbohydrates to maintain her stamina and performance. Her protein intake was also higher than recommended for vegetarian athletes. She was able to sustain faster times compared to non-vegan cyclists participating in the race. Results indicated a well-planned vegan diet is compatible with ultra-endurance mountain biking.

A study was published in Case Reports of Cardiology and examined the effects of a vegan diet on an ultra-triathlete (Triple-Ironman). Results indicated that a vegan diet provides similar athletic performance compared to an athlete using a conventional mixed diet. The report further suggests a well-planned vegan diet can apparently be adopted by ultra-endurance athletes without risk to health necessarily being incurred.

A Word From Verywell

Vegan diets continue to rise in popularity and are shown to provide numerous health benefits. Although research is lacking in plant-based diets and athletic performance, there are well-known vegan athletes who are achieving athletic success. What appears to cause continued confusion are the myths behind veganism and lack of research to debunk these untruths. More focus on the positive health benefits of eating mostly plant foods would help dispel concerns surrounding vegetarian and vegan diets.

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