PT on the Net Research

Vegetarian Athlete


More people than ever are switching to a vegetarian lifestyle. And, like the general public, some athletes have decided to embrace this form of eating as well. People choose to eat a vegetarian or vegan diet for a variety of reasons such as cultural, moral, environmental or health concerns. Headlines screaming “Mad Cow,” “Mercury and Fish,” or “Jet Fuel in Milk” has caused many to worry about the safety of food that comes from animals.

Studies typically report that 2-8% of athletes follow a vegetarian diet, with considerably more athletes following a diet that specifically excludes red meat. Vegetarian diets are more common among endurance athletes such as runners and cyclists, who are more concerned about meeting carbohydrate requirements to refuel working muscles. They will often just replace the meat on their plates with more pasta.

Vegetarianism has a certain reputation in the athletic community. People believe adhering to it will make an athlete sick and result in poor performance. Unfortunately, many coaches and trainers are still completely mystified by vegetarianism and consequently dissuade their athletes from following a vegetarian lifestyle. However, contrary to popular belief, it is entirely possible, depending on one’s own genetic make up, to have a great athletic career while consuming a plant-based diet. Carl Lewis, Martina Navratilova, Billie Jean King, Edwin Moses, Hank Aaron and six-time Ironman champion Dave Scott are examples of successes that can be achieved while following a vegetarian lifestyle.

Vegetarian diets can offer a number of advantages including lower levels of contaminated animal food and higher levels of fibre, magnesium, boron, folate, Vitamin C, Vitamin E, carotenoids and antioxidants such as phytochemicals, all of which can benefit the athletic individual. However, an athlete who consumes a poorly planned vegetarian diet or one with a genetic make up not designed for a vegetarian eating plan may be at risk for nutritional deficiencies as well as poor physical performance.

Types of Vegetarian Diets

Vegetarians are placed in various categories depending on the degree of restriction in their diets. The most common categories are:

It is likely that each person will have his or her own degree of restriction. For example, someone may follow a vegan diet but try to incorporate egg whites from a carton into their diet. In this situation, the individual may not want to eat a whole egg, but the carton egg whites bring a certain degree of disassociation from the hen that provides the egg.

Vegetarianism and Athletic Performance

The research that has been conducted to date has failed to find any significant differences in performance or lean body mass gain between athletes following any of the above vegetarian/vegans diets and a diet that contains foods of animal origin. As many studies typically report that vegetarians/vegans consume a diet higher in carbohydrates than non-vegetarians, one could assume that as long as he or she is meeting their energy, vitamin and mineral requirements, then this type of diet would be beneficial for the endurance athlete who requires a constant and adequate supply of carbohydrates for peak performance. However, if the diet results in any nutritional deficiency, then one could expect a decrease in performance.

For vegetarians/vegans, there are certain macro and micronutrients that are of particular concern. However, keep in mind that the market for vegetarian foods is increasing greatly each year, and many of these foods (e.g., meat analogs, frozen entrees) are coming fortified with nutrients such as calcium, zinc, iron, Vitamin B12, Vitamin D and riboflavin to help consumers better meet their dietary needs.

Protein

Protein consumption has always been a concern for many athletes, especially for the vegetarian/vegan athlete. As for all athletes, the needs for energy and protein are higher than for the non-athlete. Protein requirements for athletic individuals range from 1.2 to 2.0 grams per kilogram of body weight per day. Those involved primarily in endurance activities (e.g., long-distance running) require the lower end of this range, while those involved in strength activities (e.g., ice hockey) need to strive for the higher end. The assumption that vegetarian/vegan athletes are unable to meet these protein requirements is just that: an “assumption” not based on any scientific evidence. The protein myth for vegetarians/vegans stems from the fact that plant-based proteins have lower amounts of some essential amino acids and thus a lower biological value than animal-based proteins. Yet, a well-designed and regularly followed vegetarian/vegan diet can more than meet the protein needs of any athlete. However, without the proper education and guidance, an athlete can fall short in this category (this can also be true for omnivorous athletes). Vegans who do not consume eggs or dairy need to be particularly diligent.

Since plant-based protein sources such as beans and grains usually have one or more essential amino acids that are limiting (present in small amounts). It was once widely believed that foods with complementary amino acids needed to be combined during a particular meal to provide a complete protein. For example, grains such as pasta and rice are low in an essential amino acid called lysine while legumes (beans) are low in a another amino acid, but combining them (e.g., beans and rice) can create a combination of amino acids similar to that of a complete protein found in animal products. However, conscious combining of plant foods is now considered to be unnecessary as long as high-quality plant-based proteins and essential amino acids are consumed throughout the day. Amino acids are available in the blood for many hours after being eaten (an amino acid pool), and as long as the complementary amino acids appear in the next meal or two that day, the body will have what it needs to make protein (e.g., muscle synthesis). Although, after vigorous exercise, it is very important that a vegetarian/vegan athlete consume an ample amount of protein as soon as possible because the muscles are the most sensitive to amino acids during this time. Optimal recovery and growth will occur with proper nutrition.

The following is a list of good vegetarian/vegan sources of protein. For vegans, eggs and dairy products will not be an option.

Soy and hemp provide the highest quality plant protein. Gram for gram, soybean protein is just as good as milk or meat when it comes to both protein quality and amino-acid profile (contains all the essential amino acids). In other words, no combining is required. However, concerns over genetically modified soy, excessive phytoestrogen intake and the presence of allergens makes soy a question mark for some. This is where hemp protein can help fill the gap. Hemp products are becoming increasingly available in the marketplace, and the protein they contain is on a par with soy without the worry of any of the concerns associated with soy products. All vegetarian/vegan athletes should be encouraged to incorporate hemp foods such as hempseeds and hemp protein powder into a daily diet to help meet overall protein requirements. An added benefit is the essential fatty acids (omega-6 and omega-3) that hemp foods contain.

While all grains contain some protein, the quality of this source of protein can be mediocre at best. However, quinoa is one grain that stands above the rest. Quinoa contains the highest quality protein of any grain and thus can be useful in an athlete’s training diet. It also contains a wide array of vitamins and minerals and is a good source of dietary fibre.

Vegetarian/vegan athletes can use the following tips to meet their protein requirements:

Fat

Similar to the general population and meat-eater athletes, vegetarian/vegan athletes are susceptible to inadequate intakes of essential fatty acids, especially the omega-3 family (e.g., alpha-linolenic acid). Of these fats, the omega-3s present in fish (EPA/DHA) are of particular concern, as vegetarians and especially vegans have been shown to have low levels of these long-chain fatty acids. These are crucial to keeping the immune system strong and in maintaining healthy joints. EPA and DHA can be synthesized in the body from plant-based alpha-linolenic acid (ALA), which is present in flaxseed, hempseed, walnuts and some vegetable oils (e.g., canola, soybean). However, this conversion appears to be inadequate for optimal wellness. Vegetarian athletes who consume fish can meet EPA and DHA needs by consuming 2-3 servings of fatty fish (e.g., salmon, sardines) per week or by using a fish oil supplement. Vegans and vegetarians who do not consume fish products now have the option of supplementing with DHA in a non-gelatine capsule that is derived from the oil of the algae that fish consume.

Iron

All athletes, but especially female athletes, are at risk of iron deficiency. Consuming adequate iron should be a concern among vegetarians/vegans since iron stores generally tend to be lower among this population than among non-vegetarians. In addition, vegetarians/vegans may need more total iron on a daily basis as a result of a heavier reliance on foods containing poorly-absorbed plant-based non-heme iron (2-8% absorption) as opposed to the heme-iron (15-35% absorption) found in meats. The significance of this is unclear since low iron stores do not in themselves result in poor performance. However, iron deficiency anemia does result in a decrease in athletic performance, and low iron stores (non-anemic iron deficiency) are a risk factor for anemia. The main symptoms of iron deficiency anemia in an athlete are weakness and rapid fatigue upon exertion as a result of poor oxygen delivery to the working muscles. Still, one needs to keep in mind that, unlike non-anemic iron deficiency, the incidence of iron deficiency anemia is similar among athletes who are vegetarians/vegans and those who are meat eaters.

As many athletes have increased requirements for iron, and non-heme iron sources are more poorly absorbed by the body than heme iron sources, it is important for vegetarian/vegan athletes to be aware of iron-rich foods and factors that inhibit or enhance iron absorption. The main inhibitor of iron absorption in vegetarian/vegan diets is phytate, found in many plant foods. Since iron intake usually increases as phytate intake increases, effects on iron status are mitigated.

The richest sources of iron from plants are dark green leafy vegetables, soy products (e.g., TVP), blackstrap molasses, fortified breakfast cereals, legumes, whole grains, dried fruits, nuts and seeds. Dairy foods generally are deficient in iron.

Food Amount of food Iron (mg)
Soybeans, boiled 1 cup 8.8
Lentils, boiled 1 cup 6.6
Pumpkin seeds ¼ cup 5.2
Cream of wheat ½ cup 5.1
Legumes (kidney, lima, navy, black, chickpeas) 1 cup 3.6-5.2
Blackstrap molasses 1 Tbsp 3.5
Tofu, firm ½ cup 3.4 – 6.6
Spinach, cooked ½ cup 3.2
Tahini 2 Tbsp 2.7
Potatoes 1 medium 2.3
Tempeh ½ cup 2.2
Almonds 1oz 2.2
Quinoa ½ cup cooked 2.1
Cashews ¼ cup 2.1
Dates 5 1.7
Soy nuts ¼ cup 1.7
Oatmeal 1 cup 1.7
Egg 1 whole 1.5
Apricots ¼ cup dried 1.5
Raisins ½ cup 1.5
Sunflower seeds 1oz 1.4
Mushrooms ½ cup 1.4
Prunes 5 1.3
Whole wheat bread 1 slice 0.9
Bok choy, cooked ½ cup 0.9
Peanuts, dry roasted ¼ cup 0.8
Soy beverage 1 cup 0.8-1.0
Veggie “meats” fortified 1oz 0.5-1.9

Fortified cereals can have up to 18mg of non-heme iron per serving.


To increase the absorption of iron in a vegetarian/vegan diet, you can use the following strategies:

Iron stores (serum ferritin) of vegetarian athletes should be monitored regularly, and if low stores are detected, appropriate measures should be taken (e.g., dietary adjustment/supplementation). Supplementation should only be used if a blood test reveals low iron stores, as excess iron can be toxic. Just because an athlete says he or she is tired does not necessarily indicate an iron deficiency. Over training, poor overall diet and lack of sleep can all contribute to tiredness.

Calcium

It is recommended that most vegetarian athletes, depending on their individual assessment (which may vary), aim for at least 1,000 milligrams of calcium per day through diet and/or supplements.

For vegetarians who include dairy products in their diet, this should not be difficult. Achieving calcium requirements becomes more challenging for the vegan athlete. Plant sources include dark green leafy vegetables (e.g., kale, collard greens), broccoli, beans, fortified soy beverage, fortified soy yogurt, tofu made with calcium carbonate, sesame seeds, almonds, figs, seaweeds and calcium-fortified orange juice. Although plant foods contain oxalates and phytates, which can reduce calcium absorption, the calcium in plant foods is generally well absorbed. Vegetarian/vegan athletes need to be encouraged to ensure that when choosing soy beverages instead of cow’s milk, the soy beverage is fortified with at least 100mg of calcium per 100ml of fluid (e.g., 300mg per cup).

If it is determined that an athlete’s diet is inadequate in calcium, then a daily supplement should be considered (500-1000mg/day). However, since the consumption of protein from animal sources may increase calcium requirements by causing the removal of calcium from the bone to neutralize the acid produced from protein digestion, a vegetarian/vegan athlete may need less total calcium than an omnivorous athlete.

Food Amount of Food Calcium (mg)
Cultured soy yogurt, fortified ½ cup 350
Milk 1 cup 300
Orange juice – Fortified 1 cup 300
Yogurt, plain 1 cup 280-460
Blackstrap molasses 2 Tbsp 274
Yogurt, fruit 1 cup 245-385
Collard greens, cooked 1 cup 240
Cheese, cheddar 2/3 oz 155
Soy beverage – fortified 1 cup 200-500
Tofu firm – calcium set ½ cup 200-430
Blackstrap molasses 1 Tbsp 172
Cottage cheese 1% fat 1 cup 140
Tofu soft – calcium set ½ cup 140
Figs, dried 5 137
Soybeans, green ½ cup 130
Tahini 2 Tbsp 128
Spinach, cooked ½ cup 120
Okra, cooked 1 cup 107
Almonds ½ cup 95
Tempeh ½ cup 92
Kale, raw 1 cup 90
Almond butter 2 Tbsp 86
Soybeans ½ cup 85
Tempeh ½ cup 85
Ice-cream, vanilla ½ cup 85
Bok choy ½ cup 80
Soynuts, dry roasted ¼ cup 60
Legumes (chickpeas, black, navy) ½ cup 40-65
Sour cream, reduced fat 2 Tbsp 32
Broccoli, raw ½ cup 20-40

Fortified cereals can have 55-315 mg of calcium per serving.

Vitamin D

Vitamin D is essential for the proper absorption of calcium. It can be obtained through the diet or formed in the presence of sunlight. Due to the limited number of foods with adequate amounts of Vitamin D, production from the sun is very important. During the summer months, athletes are generally exposed to more sun than the general public as a result of training and competing outdoors. However, a sunscreen with an SPF of 8 or higher can significantly decrease Vitamin D synthesis. In addition, depending on the area of residence (e.g., northern latitudes), Vitamin D production from sun exposure will not be possible from late fall to early spring. Thus, vegetarian/vegan athletes obtaining insufficient sun or not eating fortified foods should consider a Vitamin D supplement with at least 400 I.U. of Vitamin D. Strict vegan athletes need to keep in mind that Vitamin D3 (cholecalciferol) is often of animal origin. Vitamin D2 (ergocalciferol) is a form acceptable to vegans but may be less bioavailable.

A potentially useful blood test for vegetarian/vegan athletes is a blood test for 25-hydroxyvitamin D (not 1,25-dihydroxyvitamin D), which can help determine Vitamin D status.

Food Amount of Food Vitamin D (IU)
Milk, fortified 1 cup 90-100
Fortified soy beverage 1 cup 85
Fortified rice beverage 1 cup 85
Margarine 1 tsp 25
Eggs 1 whole 15-25 – level changes with chicken feed

Zinc

As a component of over 200 enzymes, zinc is involved in hundreds of different metabolic pathways including DNA replication and synthesis, immune system function, endocrine (hormones) function and energy metabolism. It is considered to be a nutrient of concern for vegetarians/vegans since one of the main sources of zinc in the diet is meat, and low zinc levels have been reported in athletes during heavy training. Compounding the problem is that phytates present in plant-based foods bind to zinc, while animal protein is believed to enhance zinc absorption. Zinc can be obtained from vegetarian sources such as pumpkin seeds, pecans, split peas, Brazil nuts, rye, whole wheat, wheat germ, oats, peanuts, walnuts, almonds, lima beans, fortified cereals and buckwheat. Similar to iron, compensatory mechanisms such as soaking and sprouting beans, grains and seeds can reduce binding of zinc by phytates and increase bioavailability. Even though it is generally clear that vegetarians/vegans have lower zinc stores, adverse health effects from lower zinc status have not been demonstrated with varied vegetarian diets in developed countries.

Food Amount of Food Zinc (mg)
Soy nuts, dry roasted ½ cup 4.2
Pumpkin seeds 1.4 cup 2.6
Navy beans ½ cup 2.3
Yogurt, plain 1 cup 2.2
Sunflower seeds ¼ cup 1.8
Wheat germ 2 Tbsp 1.8
Baked beans without pork ½ cup 1.7
Cashews, dry roasted 1oz 1.6
Tahini 2 Tbsp 1.4
Pecans, dry roasted 1oz 1.4
Chick peas ½ cup 1.3
Lentils ½ cup 1.2
Peanuts, dry roasted ¼ cup 1.2
Cheese, Swiss 1oz 1.1
Almonds, dry roasted 1oz 1.0
Milk 1 cup 1.0
Soybeans, cooked ½ cup 1.0
Walnuts 1oz 1.0
Tofu, firm ½ cup 1.0
Cheese, cheddar 1oz 0.9
Peanut butter 2 Tbsp 0.9
Milk 1 cup 0.9
Tempeh ½ cup 0.9
Cheese, cheddar 1oz 0.9
Kidney beans ½ cup 0.8
Yogurt ½ cup 0.8-1.1
Green peas ½ cup 0.8
Oatmeal, instant 1 packet 0.8
Quinoa, cooked ½ cup 0.8
Mushrooms ½ cup 0.7
Soy beverage 1 cup 0.6
Eggs 1 whole 0.5
Bread, Whole wheat 1 slice 0.5

Fortified cereals can range from 0.7 to 15mg of zinc per serving.


Vitamin B12

Vitamin B12 is needed for cellular growth and nervous system development, and a deficiency of B12 can play a role in iron- and exercise-induced anemia. Meat eaters acquire B12 through micro-organisms living in the animal flesh they eat. Lacto-ovo- vegetarians can get their B12 through eggs and dairy products. Obtaining B12 in a vegan diet is more difficult as no plant food, unless fortified, contains significant amounts of active Vitamin B12.

Sources of vegetarian/vegan B12 include: fortified soy beverage, Red Star nutritional yeast, fermented soy products and potentially surface bacteria on lightly washed organic produce. Despite a lack of reliable sources of dietary Vitamin B12 in a vegan diet, long-term studies have observed low rates of deficiency in vegans. This may have a lot to do with the fact that the human body can store a 2-7 year supply of vitamin B12. A possible contributor to this low detection of deficiency is that vegetarian/vegan diets tend to be high in foliate, which can mask the haematological symptoms of Vitamin B12 deficiency. To be on the safe side, vegetarian/vegan athletes should consider a Vitamin B12 supplement to help cover their needs.

Food Amount of Food B12 (mcg)
Nutritional yeast (Red Star) 1 Tbsp 1.5
Veggie “meats”, fortified 1oz 0.5-1.2
Eggs 1 whole 0.5
Soy beverage, fortified ½ cup 0.4-1.6
Cow’s milk ½ cup 0.4-0.5

Fortified cereals can have 0.6 to 6.0 mcg per serving of vitamin B12.


Although sea vegetables and spirulina contain significant amounts of Vitamin B12, the types of vitamin they contain are B12 analogs and are most likely not bioavailable to humans.

Riboflavin

In addition to Vitamin B12, riboflavin (B2) intake can be low in vegan athletes, mainly because no dairy products are consumed. Riboflavin is necessary for the production of energy (ATP) and therefore essential to athletic performance. Plant sources include fortified grains, soybeans, dark green leafy vegetables, sweet potatoes, wheat germ, avocados, nuts, bananas, kale, beans and sea vegetables. Vegan athletes need to be encouraged to incorporate these foods as part of a balanced diet.

Sugar

Unfortunately, many vegetarian/vegan foods can be high in added sugars (e.g., soy yogurt, flavoured soy beverage, supplement bars and cereals). A trip to a vegetarian food fair will reveal a fair share of overweight vegetarians. Generally extra sugars should not be a significant problem for those who are very active, but for those athletes concerned about their body weight and body fat, there is a need to be cautious. Choosing plain soy beverages and low-sugar cereals can help decrease added sugar intake.

Supplementation

The following is a list of potentially useful supplements for the vegetarian/vegan athlete:

Traveling

Vegetarian/vegan athletes training or competing away from home can find it difficult to follow their dietary lifestyle to the degree that is needed to achieve maximum results. These athletes should determine ahead of time what foods will be available and then provide for any deficiencies by bringing what is required with them on the road. For example, packing some protein powder can help fill a protein need on the road when only protein from meat is available.

A Final Note

For optimal health and performance, vegetarian/vegan athletes need to increase their dietary repertoire beyond the standard tofu, beans and rice. The use of molasses, wheat germ and hemp protein in a post-workout shake; experimentation with sprouting; the addition of various nut butters to whole grain crackers; and tempeh burgers with quinoa for dinner are all ways to accomplish this. Proper education is a must. Coaches and trainers with little understanding of this dietary lifestyle are not appropriate sources for nutritional education. Also, some athletes, based on their genetic make up, will not respond properly to a strict vegetarian lifestyle no matter how educated they are on the matter. What is good for the goose is not always good for the gander.  (For a basic description of metabolic typing and how this may effect an individual’s nutritional requirements, see Noah Hittner’s Q&A on " Metabolic Typing .")

References

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