Vegetarian Diet and Sport

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Vegetarian Diet and Sport
5th EduSportInternational Summer School

• Cristina Angeloni, PhD
• University of Bologna
• Department of Biochemistry G. Moruzzi
• Nutrition Research Center

September 17th 2008, Rimini
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Vegetarian diet a growing phenomenon

• 2.5 of American adults and 4 of Canadian report
  following a vegetarian diet.
• Motivations
• religious or cultural customs,
• perceived health benefits,
• ethical or philosophical beliefs,
• concern for the environment and animal welfare
  factors,
• world hunger.

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Characteristics of vegetarianism

• Advantages
• Lower levels of
• Satured fat
• Cholesterol
• Higher levels of
• Carbohydrates
• Fiber
• Magnesium
• Folate
• Antioxidants
• Vitamins C and E
• Carotenoids
• Phytochemicals

• Disadvantages
• Lower levels of
• Iron
• Vitamin B12
• Vitamin D
• Calcium
• Zinc
• Riboflavin

American Dietetic Association, Dietitians of
Canada. Vegetarian diets. J Am Diet Assoc
2003103748
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Health implications of vegetarianism

• Reduced risks for
• obesity,
• type 2 diabetes,
• hypertension,
• cardiovascular disease,
• some cancers.

Key TJ, et al. Am J Clin Nutr 199970(suppl)516S
Key TJ, et al. Proc Nutr Soc 199958271 Fraser
GE. Am J Clin Nutr 199970(suppl)532S
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Macronutrients

• Proteins
• Carbohydrates

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Typical protein recommendations for athletes

• 1.2 to 1.4 g/kg/d for endurance athletes
• up to 1.7 g/kg/d for resistance and
  strength-trained athletes

Do vegetarian athletes require more proteins than
non-vegetarian athletes?

• American Dietetic Association, Dietitians of
  Canada, American College of Sports Medicine. J Am
  Diet Assoc 20001001543

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Vegetarian athletes and protein

• Observational studies of vegetarian and non
  vegetarian athletes have not found differences in
  performance associated with the amount of animal
  protein consumed.
• Hanne N et al. J Sports Med Phys Fitness
  198626180
• Cotes JE et al. J Physiol 1970209(suppl)30P
• Nieman DC. Am J Clin Nutr 198848(suppl)754
• Richter EA et al. Med Sci Sports Exerc
  199123517

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Effect of exercise and vegetarianism on protein
requirements

• Separate recommendations for protein consumption
  are not required for vegetarians who consume
  dairy products or eggs and complementary mixtures
  of high-quality plant proteins.

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Effect of exercise and vegetarianism on protein
requirements

• Plant proteins may be limiting in
• lysine
• threonine,
• tryptophan,
• sulfur-containing amino acids.
• The issue of protein quality is recognized as a
  potential concern for individuals who avoid all
  animal protein sources

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Food And Nutrition Board/Institute Of Medicine
Scoring Pattern
It represents mg of an essential amino acid that
must be present per g of dietary protein to meet
the recommended daily allowance for the essential
amino acid when total protein intake is equal to
the recommended daily allowance.
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Lysine intake of vegetarians

• 50 kg adultRDA for protein 40 g/d (0.8 g/kg/d x
  50 kg)RDA for lysine 2 g/d (38 mg/kg/d x 50
  kg)
• If that individual consumes a diet containing 40
  g of protein, 25 of which provided from wheat,
  rice, almonds, this would provide only 1.6 g of
  lysine.
• However, if total protein intake is increased to
  50 g or more, this would provide at least 2 g of
  lysine.

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Protein intakes of vegetarians

• Vegetarians protein intakes are lower than those
  of omnivores.
• American Dietetic Association, J Am Diet Assoc
  2003103748
• Barr SI et al. J Am Coll Nutr 200019781
• Larsson CL et al. Am J Clin Nutr 20026100

But vegetarians protein intakes are generally
well above the RDA
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Protein intakes

• Vegans
• 10-12
• Lacto-ovo-vegetarians
• 12-14
• Omivores
• 14-18

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Protein intakes of active vegetarians

• 50 kg vegetarian young woman
• If she was a vegetarian with a relatively low
  protein intake (e.g., 11 of energy)
• her diet would provide 55 g/d of protein
• If she was an athlete expending 3000 kcal/d with
  11 from protein,
• her protein intake would further increase to 82
  g/d.

The possible exception could be athletes
following low-protein vegan diets who are also
attempting to limit their energy intake.
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Carbohydrate

• Recommendations for athletes 6-10 g/kg body
  weight
• Diets of omnivores and vegetarians can readily
  provide from 7 to 8 g of carbohydrate per kg of
  body weight per day

60 kg endurance athlete expending 3600 kcal/d
would receive more than 8 g of carbohydrate per
kg of body weight per day even if the diet
provided only 55 of energy from carbohydrate.

• American Dietetic Association, Dietitians of
  Canada, American College of Sports Medicine. J Am
  Diet Assoc 20001001543

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Micronutrients

• Iron
• Vitamin B12
• Antioxidants

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Iron

• Iron occurs in the food supply in two chemical
  forms
• Heme
• 40 of the iron in meat, fish, and poultry.
• about 15 to 40 absorption
• Non-heme
• the remaining iron in meat, fish, and poultry and
  all iron in other foods
• about 1 to 15 absorption,

Vegetarian diets contain no heme iron
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Iron balance

• Total iron intake of vegetarians than that of
  omnivores.
• Total iron intake provides almost no indication
  of the amount of absorbed iron, which varies
  inversely with body iron stores and is influenced
  by different factors.

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Iron absorption

• Inhibitors
• phytate
• calcium and phosphate salts
• polyphenols in tea
• coffee
• cocoa
• some spices
• fibers

• Enhancers
• vitamin C
• alcohol
• retinol
• carotenoids

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Recommended iron intake for vegetarians

• Recommended iron intakes for vegetarians are
  increased by 80 to compensate for the reduced
  bioavailability of iron from vegetarian diets.
• RDAs for omnivorous adult men and premenopausal
  women are 8 mg/d and 18 mg/d respectively
• RDAs for vegetarians 14 mg/d and 32 mg/d

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Vitamin B12

• Inadequate intakes of vitamin B12 will lead to
  macrocytic anemia that is associated with reduced
  oxygen transport.

Vegetarians who exclude all foods from animal
sources do not have a reliable source of vitamin
B12 in their diet
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Vitamin B12

• An additional concern about vitamin B12
  deficiency in vegetarians is that macrocytic
  anemia may be masked by high folate intakes,
  which would be expected higher in vegetarians.

Vegan athletes need to include synthetic vitamin
B12 in their diets to prevent macrocytic anemia.
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O2
ROS
Protein
DNA
LIPIDS
enzyme inactivation
genetic mutation
membrane function
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Antioxidant status of vegetarians

• Plasma vitamin C , E and ß-carotene
  concentrations are consistently higher in
  vegetarians than in omnivores.
• Rauma AL, Mykkanen H. Antioxidant status in
  vegetarians versus omnivores.Nutrition
  200016111
• Fruit and vegetable are rich source of
  phytochemicals that are antioxidants
• Polyphenols
• Glucosinolates

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Creatine

• Creatine is found in meat, fish, and poultry.
• Typical omnivorous diets provide 1 g/d.
• Creatine is also synthesized endogenously at a
  rate of about 1 g/d.
• A large majority of the body creatine pool is
  found in muscle, primarily in the form of
  phosphocreatine, and serves as a temporary
  storage site for ATP.

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Creatine in vegetarians

• Adopting a vegetarian diet lead to a reduction in
  muscle creatine concentration.
• Lukaszuk JM et al. Int J Sport Nutr Exerc Metab
  200212336
• It could be hypothesized that vegetarians
  performances could be impaired in athletic events
  that rely on the high-energy phosphate system
• Burke et al. suggested that vegetarians
  experience a greater benefit from creatine
  supplementation than do omnivores.
• Burke DG et al. Med Sci Sports Exerc 2003351946

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The Female Athlete Triad

• The female athlete triad denotes a combination of
  three conditions that can affect female athletes
• disordered eating,
• amenorrhea,
• osteoporosis.
• The consequences of the female athlete triad are
  serious with respect to athletic performance in
  the short term and to reproductive and bone
  health in the long term.

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Vegetarianism and the female athlete triad

• A vegetarian diet could be associated with
  disordered eating habits
• Menstrual cycle disturbances may be more common
  among vegetarians
• A LOV diet does not appear to predispose one to
  osteoporosis however, vegan diets are typically
  low in calcium and may be associated with lower
  bone mineral density

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Young vegetarian athletes

• A well-planned vegetarian diet can support normal
  growth and development.
• Adolescents following a restrictive diet have
  lower intakes of vitamin B12 and calcium, and
  their serum ferritin levels are lower. Tests of
  cognitive functioning found reductions in
  performance among those who were deficient in
  vitamin B12.
• Because of the potential bulk of a vegetarian
  diet it may be challenging for young athletes to
  meet their energy needs

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Does vegetarianism have any implication on
athlets performances?
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Assessing the effects of a vegetarian diet on
performance

• Vegan diet does not impair the physiological
  response to submaximal exercise.
• No significant differences in fitness parameters
  were found between vegetarian and non-vegetarian
  athletes in a variety of physical fitness,
  anthropometric and metabolic measures
• Lacto-ovo-vegetarian diet does not affect
  endurance performances

Venderley AM and Campbell WW, Sport Med 2006
36293-305
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Conclusions

• A well-planned vegetarian diets appear to
  effectively support athletic performance
• Vegetarian diets provide protein intakes
  adequated to meet needs for total nitrogen and
  the essential amino acids
• Vegetarians are at increased risk for non-anemic
  iron deficiency, which may limit endurance
  performance
• Vegetarians have lower mean muscle creatine
  concentrations than do omnivores, and this may
  affect supramaximal exercise performance

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Who is this man?
1983 World championship 3 gold medals
1984 Olympic games 4 gold medals 1987 World
championship 3 gold medals 1988 Olympic games
2 gold medals 1991 World championship 2 gold
medals 1992 Olympic games 2 gold medals
1996 Olympic games 1 gold medals
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Thanks for the your attention!

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