Microsoft PowerPoint - 0527_ANGELONI Cristina_ Vegetarian Diet

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					                  6th EduSport
         International Summer School

Vegetarian Diet and Sport
            Cristina Angeloni, PhD

                 University of Bologna
         Department of Biochemistry G. Moruzzi
               Nutrition Research Center

              May 27th 2009, Rimini
   What we will cover today…

Definition of the most practiced vegetarian diets
Health implication of vegetarianism
Energy requirements for vegetarian athletes
Macronutrient requirements for vegetarian
Micronutrient requirements for vegetarian
Vegetarian diet as a source of phytochemicals
Creatine status in vegetarian athletes
Implications of vegetarianism on athletic
Nutrition and sport

 Since the time of the ancient
  Greeks, athletes and their
coaches have practiced special
 dietary regimens to improve
    Vegetarian diet:
    a growing phenomenon

2.5% of American adults and 4% of Canadian report
following a vegetarian diet.

•   perceived health benefits
•   animal welfare factors
•   concern for the environment
•   religious or cultural customs
•   ethical or philosophical beliefs
•   world hunger
Characteristics of vegetarianism
     Lower levels of:
         • levels of:
      Lower Satured fat
         •• Cholesterol
             Animal proteins
          • Iron
     Higher levels of:B
          • Vitamin 12
         •• Carbohydrates
             Vitamin D
         •• Fiber
         •• Magnesium
         •• Folate
         • Antioxidants:
                 • Vitamins C and E
                 • Carotenoids
           • Phytochemicals

  American Dietetic Association, Dietitians of Canada. Vegetarian diets. J Am
  Diet Assoc 2003;103:748
Health implications of

Reduced risks for:
  type 2 diabetes,
  cardiovascular disease,
  some cancers.

              Key TJ, et al. Am J Clin Nutr 1999;70(suppl):516S
              Key TJ, et al. Proc Nutr Soc 1999;58:271
              Fraser GE. Am J Clin Nutr 1999;70(suppl):532S
    Energy requirement for atheltes

Optimum athletic performance is promoted by adequate
energy intake
Energy needs range from 2000 to 6000 kcal/day or more

Energy expenditure for different types of exercise is
dependent on:
 • Duration, frequency, intensity of the exercise.
 • Sex of the athlete
 • Prior nutritional status
 • Heredity
 • Age
 • Body size
 • Fat-free mass
       Energy requirement for
       vegetarian athletes
Vegetarian diets are capable of providing sufficient
energy to meet an athlete's need.

Energy intake among vegetarians are typically lower
than non-vegetarians

Only athletes consuming a vegan diet may be
challenged to consume sufficient quantities of food
to meet their energy needs.

 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. Med Sci Sport Exerc. 2009:709-730
     Effect of exercise and
     vegetarianism on protein
  Separate recommendations for protein
    consumption are not required for
vegetarians who consume dairy products or
eggs and complementary mixtures of high-
           quality plant proteins.
  Effect of exercise and
  vegetarianism on protein

The issue of protein quality is recognized as a
potential concern for individuals who avoid all
animal protein sources

Plant proteins may be limiting in:
 • lysine
 • threonine,
 • tryptophan,
 • sulfur-containing amino acids.
Food And Nutrition
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.
 Lysine intake of vegetarians
50 kg adult
RDA 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

However, if total protein intake is increased to
50 g or more, this would provide at least 2 g of
                  Protein intakes of vegetarians

Vegetarians’ protein intakes are lower than those of
   •   American Dietetic Association, J Am Diet Assoc 2003;103:748
   •   Barr SI et al. J Am Coll Nutr 2000;19:781
   •   Larsson CL et al. Am J Clin Nutr 2002;6:100

                          But vegetarians’ protein intakes are
                            generally well above the RDA
 Protein intakes
 % of daily energy

 • 10-12%

 • 12-14%

• 14-18%
    Protein intakes of active
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.
     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 1986;26:180
 •   Cotes JE et al. J Physiol 1970;209(suppl):30P
 •   Nieman DC. Am J Clin Nutr 1988;48(suppl):754
 •   Richter EA et al. Med Sci Sports Exerc 1991;23:517
       Typical carbohydrate
       recommendations for athletes
6 to 10 g kg-1 body weight d-1

Carbohydrates maintain blood glucose levels during
exercise and replace muscle glycogen.

The amount required depends on the athlete’s:
 • total daily energey expenditure,
 • type of sport,
 • sex,
 • environmental conditions

               American Dietetic Association, Dietitians of Canada, American
               College of Sports Medicine. Med Sci Sport Exerc. 2009:709-730

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 provides only 55% of
                 energy from carbohydrate.

             American Dietetic Association, Dietitians of Canada, American
             College of Sports Medicine. J Am Diet Assoc 2000;100:1543
       Typical fat recommendations
       for athletes
Fat intake should range from 20% to 30% of total
energy intake
Consuming ≤20% of energy from fat does not benefit
Fat are important in the diet of athletes because are
source of
 • Energy
 • Fat soluble vitamins
 • Essential fatty acids

                            High-fat diets
              American Dietetic Association, Dietitians of Canada, American
              College of Sports Medicine. Med Sci Sport Exerc. 2009:709-730
             are not recommended for athletes
Fats and vegetarian atheltes
Vegetarians’ fat intake is compatible with athletic
energy requirements and performances

Vegetable fats and oils have a higher nutritional quality
than animal fats

Healthier fat choices are:
 • nuts,
 • seeds,
 • olive oil,
 • canola oil,
 • fish,
                             These are typical
 • avocados,
                           vegetarians’ choices
 • olives
       Fats and vegetarian atheltes

Whereas vegetarian diets are generally rich in n-6
fatty acids, these diets can be low in n-3 fatty acids
inhibiting the synthesis of EPA and DHA

Diets that do not include fish, eggs, or generous
amount of sea vegetables generally lack of direct
sources of EPA and DHA.

         Position of the American Dietetic Association and Dietitians
         of Canada. J Am Diet Assoc 2003; 103, 748-765.
  Vitamin B12
 Iron and athletic performance

Iron is required for the formation of oxygen
carrying proteins, and for enzymes involved in
energy production.

Oxygen carrying capacity is essential for
endurance exercise

Iron depletion is one of the most prevalent
nutrient deficiencies observed among athletes,
especially females

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
       Iron balance

Total iron intake of vegetarians ≥ than that of

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
Iron absorption
  Inhibitors          Enhancers
   • phytate          • vitamin C
   • calcium and      • alcohol
     phosphate        • retinol
                      • carotenoids
   • polyphenols in
     tea, coffee,
   • some spices
   • fibers
   Vegetarians’ iron absorption

The main inhibitor of iron absorption in vegetarian
diets is phytate.

Because iron intake increases as phytate intake
increases, effects on iron status are somewhat
less than might be expected.

Fiber appears to have a minor effect on iron

Vitamin C and organic acids in fruits and
vegetables consumed at the same time as the
iron source, can help to reduce the inhibitory
effects of phytate
      Recommended iron intake for
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
Vitamin B12 and athletic

  Vitamin B12 is required for the
 production of red blood cells, for
 protein synthesis, and in tissue
repair and maintenance including
            the CNS
        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
       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.

 DNA                        Protein

genetic         membrane    inactivation
mutation         function
          Antioxidant status of
Plasma vitamin C , E and β-carotene concentrations
are consistently higher in vegetarians than in
•   Rauma AL, Mykkanen H. Antioxidant status in vegetarians versus omnivores.Nutrition

Fruit and vegetable are rich source of
phytochemicals that are antioxidants:
 • Polyphenols
 • Glucosinolates

Phytochemicals are secondary plant metabolites

Functions are varied:
 • UV screens / antioxidants
 • Protection from certain types of herbivory (anti-feedants)
 • Protection from pathogen attack
 • Function in wound healing
 • Plant pigments (attract pollinators)

Many phytochemicals are bioactive food component
 • nonessential biomolecules that are present in foods and
   exert biological activity in mammalian systems resulting in
   the promotion of better health
                 Phytochemicals as functional foods

Functional    foods are foods           with
components recognized for their extra
benefits to human health. They do more
than just meet our basic nutritional needs
“Food for Specified Health Use”

The concept of functional
foods was established in
Japan in 1991
 According to European consensus
 document the unique features of
 functional foods are:

Conventional or every day food;

Consumed as part of a normal diet;

Composed of naturally occurring

Having a positive effect on physiological
function beyond nutritive value

Having authorized and scientifically
substantiated health claims
         “Functional” Diet
         “Functional” Diet
Institutions like FAO and WHO recommend a
daily intake of at least 400 g of fruits and
vegetables a day, if possible in 5 different
    Eat the colours of life                    The five
                                              colours of



 White                    Yellow-Orange

Are the most important source of Lycopene

 • Powerful antioxidant
 • Prevents/Counteracts some forms of cancers
 • Is inversely associated with risk for cardiovascular
   Lycopene Content of Foods

                   mg/100 g wet wt
Tomatoes, fresh    2.0
Tomatoes, canned   3.7
Tomato sauce       6.2
Tomato paste       5.4-15.0
Tomato juice       5.0-12
Pizza sauce        13
Ketchup            12
Grapefruit, pink   4
Watermelon         5
Broccoli and other cruciferous
Broccoli are the most abundant source of

Sulforaphane is an indirect antioxidant

Epidemiological evidence has associated the
frequent consumption of cruciferous
vegetables with decreased cancer risk

Sulforaphane consumption has been
associated with a reduction of cardiovascular
disease risk
        Historic Uses

Used historically in China for many different ailments

Used as a currency
              Green Tea
500 A.D. Demand rises, and farmers begin to cultivate tea
    Green Tea

Is rich in flavonoids like epicatechins

Epicatechines are antioxindats

Green tea consuption has been associated to
reduced cancer and cardiovascular disease risks

How green tea is made:

• Leaves are usually picked by hand
• Leaves are steamed, rolled, and dried
  immediately and completely
   • Epicatechins are not modified like black
Objective: This study investigated the effects of the consumption of green tea (GT)
for 7 d on biomarkers of oxidative stress in young men undergoing resistance

 Conclusion: Consumption of Green Tea, a beverage rich
in polyphenols, may offer protection against the oxidative
  damage caused by exercise, and dietary guidance for
        sports participants should be emphasized.

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.
            Creatine metabolism


                     + ATP

   Larger body creatine pool could prolong
                          + ADP + H+ shorten
supramaximal intensity exercise and/or
   recovery time between repeated bouts of
           supramaximal exercise
    Creatine in vegetarians
Adopting a vegetarian diet can lead to a
reduction in muscle creatine concentration.
•   Lukaszuk JM et al. Int J Sport Nutr Exerc Metab 2002;12:336

It could be hypothesized that vegetarians’
performances could be impaired in athletic
events that rely on the high-energy phosphate

It has been suggested that vegetarians
experience a greater benefit from creatine
supplementation than do omnivores.
•   Burke DG et al. Med Sci Sports Exerc 2003;35:1946
   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
Does vegetarianism have any
implication on athlets performances?
  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; 36;293-305

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
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
Thanks for the your attention!


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