KNES 337 - Unit 16 Vegetarian Diets

vegan

excludes all animal derived foods

lactovegetarian

includes milk products

lacto-ovo-vegetarian

include milk and egg

partial vegetarian

excludes red mean (chicken is fine)

pesco-vegetarian

excludes poultry and red mean (only fish and pesco meat)

health benefits

• Research shows (on average)

  • Lower body weight

  • Lower blood pressure

  • Less heart disease

  • Lower mortality from cancer, especially colon

at risk nutrients

• The more restrictive the diet, the more likely you are to be at risk

• Highest risk is vegan diet 

• e.g. protein, iron, zinc, calcium, vitamin D, vitamin B₁₂

protein

• Complete proteins = animal sources, incomplete = plant protein

• Just eat complementary proteins:

  • Grains and legumes (e.g. beans and rice)

  • Milk and grains

  • Milk and legumes 

iron

• Iron in plant foods (non-heme) - legumes, dark green leafy vegetables, iron-fortified cereals, whole grain breads, cereals → more poorly absorbed than animal sources of iron (heme) 

• Vitamin C enhances absorption of non-heme (plant sources of iron)

• Iron absorption from mixed diet with meat, fish, and poultry = 14-18%

• Iron absorption from vegetarian diet = 5-12%

iron absorption from mixed diet

(consuming meat, fish, poultry) = 14-18%

iron absorption from vegetarian diet

= 5-12%

non-heme iron

legumes, dark green leafy vegetables, iron-fortified cereals, whole grain breads, cereals → more poorly absorbed

heme iron

found in animal sources - better absorbed

zinc

• Meat is rich source

• Seafood also good source

• Whole grains, nuts, legumes

• Critical for immune function and growth 

• In developing countries, zinc deficiency is caused by high cereal protein intake, rich in phytates (anti-nutrition factor), which makes zinc unavailable for absorption

  • Especially if you’re a child

high cereal protein

can cause zinc deficiency 

rich in phytates (an anti-nutrition factor) = makes zinc unavailable for absorption especially in children

calcium

• Most reliable - milk (animal sources have highly absorbable calcium)

• Calcium-fortified juices, soy, almond, oat milk to replace cow’s milk 

  • Make sure enough calcium

• Other sources - calcium-set tofu, some legumes (navy and white beans), almonds, tahini and chia seeds

• Oxalate (anti-nutrition factors) - binds calcium, can’t be absorbed 

  • Lower oxalate vegetables - turnip greens, broccoli, kale considered better sources for calcium

  • Higher oxalate vegetables - spinach, beet greens, Swiss chard

  • Boiling can reduce oxalate levels by 30-87% (more effective than steaming or baking)

oxalate

an anti-nutrition factor - binds calcium, can’t be absorbed 

• Lower oxalate vegetables - turnip greens, broccoli, kale considered better sources for calcium

• Higher oxalate vegetables - spinach, beet greens, Swiss chard

• Boiling can reduce oxalate levels by 30-87% (more effective than steaming or baking)

vitamin D

• Vitamin D fortified milk 

• Exposure to sunlight (northern climates limited)

• Supplement likely necessary

• Alberta Health Services says all Albertans should be consuming a vitamin D supplement (regardless of diet)

vitamin B12

• Only in animal foods - eggs, meat, poultry, shellfish, milk 

  • Fortified soy milk or breakfast cereals or supplement 

populations at greater risk of deficiency

 pregnancy and lactation, infancy, childhood and adolescence (more growth needs)