Making the case for vegetarian diets!
Joan Sabaté, MD, DrPH !
Vegetarian diets are ffffffffffffffff of eating.
The roots of vegetarian diets can be traced back to the
beginnings of recorded history.
The book of Genesis!Pronounces that the seeds of plants and the fruits of trees are the nourishment of human kind.
“The eating of meat extinguishes the seed of great compassion.”
Gautama Buddha!
Plato!The Republic asserted that the ideal city was a vegetarian city because it was more rational to choose a diet less harmful to the environment and to the spirit.
Vegetarian diets are not a
modern invention or fad from a
recent book.
A vegetarian diet is defined by the exclusion of flesh foods.
How are the dietary patterns defined?!
Non-vegetarian!
Pesco!
Lacto-ovo!
Vegan!
Meat! Poultry/Fish! Dairy/Eggs!
Most studies of vegetarians "come from either the: "
"North-American Seventh-day
Adventists Cohorts (AHS-1 & 2)!or"
the EPIC-Oxford study in the UK. !
Health effects of vegetarian diets!
CVD risk factors!
Vegetarians weigh less!
100
120
140
160
180
200
Vegan Lacto-ovo
Wei
ght (
lbs)!
0!
Female 5’ 6” tall! Male 5’ 10” tall!
Adventist Health Study
Vegetarians have lower BMI!
Vegans!
Meat-eaters!
Fish eaters!
Vegetarians!
EPIC-Oxford Study
Vegetarians have lower risk of diabetes!
0%
2%
4%
6%
8%
2.1%!
3.2%!
4.7%!
7.5%!
Vegan Lacto-‐ovo Pesco-‐veg Non-‐veg
% R
epor
ting
Type
2 D
iabe
tes!
Adventist Health Study
• 2–5 points lower BMI
• 25% - 50% lower risk of hypertension
• 25% to 50% lower risk of diabetes
• 50% lower risk of metabolic syndrome
Vegetarians compared to !non-vegetarians have:!
IHD mortality of vegetarians!
1!
0.81!
0.88!
0.71!
0.5
0.6
0.7
0.8
0.9
1
Meat eater Vegetarian
Veg Women Veg Men
Adju
sted
Haz
ard
Ratio
(HR)!
Adventist Health Study
Vegetarians have a slightly lower risk of overall-cancers!
1!
0.92!0.98!
0.88!
0.93!
0.5
0.6
0.7
0.8
0.9
1
Non-‐vegetarian Vegetarian
Pesco-‐V Lacto-‐V
Vegan
Adju
sted
Haz
ard
Ratio
(HR)!
A Vegetarian diet seems to reduce the risk of some cancer sites (colorectal, prostate, GI tract) while it has no
effect on other cancers.
All-Cause mortality for vegetarians!
1!
0.88!0.93!
0.82!
0.5
0.6
0.7
0.8
0.9
1
Meat eater Vegetarian
Veg Women Veg Men
Adju
sted
Haz
ard
Ratio
(HR)!
Adventist Health Study
Longevity"In general, vegetarians live 2 – 3
years longer than non-vegetarians.
What do vegetarians eat?!
Relative food intake of vegetarians compared to non-vegetarians!
0.00 0.50 1.00 1.50 2.00 2.50 3.00
drinking water beverages
snack foods sweets
added fats eggs
dairy products meat
nuts & seeds soy foods & meat analogues
legumes grains
potatoes avocados
vegetables fruit
* Means, adjusted for age, sex & race and standardized to 2000kcal)!
Vegan vs. Nonveg
Lacto vs. Nonveg
Pesco vs. Nonveg
Adventist Health Study
Animal protein foods!
0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40
unprocessed red meat
processed red meat
unprocessed poultry
processed poultry
pork
faHy fish
other fish
regular milk products
reduced milk products
cheese
eggs
Rela1ve mean quan1ty eaten compared to non vegetarians (adjusted for age, sex & race and standardized to 2000kcal)
Vegan vs. Nonveg
Lacto vs. Nonveg
Pesco vs. Nonveg
Adventist Health Study
Plant protein foods!
0.00 1.00 2.00 3.00 4.00 5.00 6.00
legumes
meat analogues
soybeans & tofu
soymilks
peanuts
peanut buHer
tree nuts
mixed nuts
seeds
Rela1ve mean quan1ty eaten compared to non vegetarians (adjusted for age, sex & race and standardized to 2000kcal)
Vegan vs. Nonveg
Lacto vs. Nonveg
Pesco vs. Nonveg
Adventist Health Study
Fruits and vegetables!
0.00 0.50 1.00 1.50 2.00 2.50 3.00
avocados
tomatoes
leafy greens
cruciferous vegetables
onions
other vegetables
citrus
berries
other fruits
dried fruits
Rela1ve mean quan1ty eaten compared to non vegetarians (adjusted for age, sex & race and standardized to 2000kcal)
Vegan vs. Nonveg
Lacto vs. Nonveg
Pesco vs. Nonveg
Adventist Health Study
0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
whole grains
refined grains
mixed grains
sweet potatoes
white potatoes
fried potatoes
Rela1ve mean quan1ty eaten compared to non vegetarians (adjusted for age, sex & race and standardized to 2000kcal)
Vegan vs. Nonveg
Lacto vs. Nonveg
Pesco vs. Nonveg
Starchy foods!
Adventist Health Study
Fats, Sweets & Snacks!
0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40
solid fat
liquid fat
salad dressing
buHer
dairy dessert
other dessert
Rela1ve mean quan1ty eaten compared to non vegetarians (adjusted for age, sex & race and standardized to 2000kcal)
Vegan vs. Nonveg
Lacto vs. Nonveg
Pesco vs. Nonveg
Adventist Health Study
• More plant foods • Less dairy and eggs • Less refined foods • Less beverages • And more water
A healthy vegetarian diet includes:!
Sustainability of Vegetarian diets!
""
The production of Plant foods "is more sustainable because:"
""
they require fewer natural resources ""
are less taxing on the environment "compared to production of animal foods.
Not all foods are produced equally!
Green house Gas emissions in the production of different foods!
Post-‐producMon emissions
ProducMon emissions
0
2
4
6
8
10
12
14
16
18
20
Land Water Fuel FerMlizer PesMcide Animal waste
Rela
tive
Envi
ronm
enta
l Im
pact! Beans Almonds Eggs Chicken Beef
*Beans as the reference value =1!!
Sabate et al., 2014
Relative environmental impacts of protein production from plants vs. animal sources!
0 10 20 30 40 50 60 70 80 90 100
FerMlizer
PesMcide
Energy
Water
Moderate Meat diet Vegetarian diet
Marlow et al., 2015
The production of foods within a vegetarian diet requires less resources!
Adventist Health Study
0 1 2 3 4 5 6 7 8
High meat-‐eaters (≥100 g/day)
Medium meat-‐eaters (50–99 g/day)
Low meat-‐eaters (<50 g/day)
Fish-‐eaters
Vegetarians
Vegans
Scarborough et al., 2014.!
kg CO2e/2000 kcals!
The production of all foods within vegetarian diets emits less GHGe!
EPIC-Oxford Study!
*Adjusted to 2000 kcal!
0 0.5 1 1.5 2 2.5 3
Moderate Meat
Low Meat
Vegetarian
Plant Foods Meat Dairy/Eggs Beverages
17%! 14%!
13%!
20%! 19%! 17%!
29% decr
22% decrease!
68%!
59%!
40%!
15%!
6%!
kg CO2e/d!
Soret et al., 2014 Adventist Health Study
The production of foods within a vegetarian diet emits less GHGe!
“The adoption of vegetarian diets at the global level has the potential to, all at once, optimize the food supply, improve human health, increase environmental sustainability, and advance social justice outcomes.”!
Sabate and Soret 2014
Making the case for vegetarian diets!
Simple – easy to understand and practice. Adaptable – many cultures and cuisines. Healthy - lower risk for chronic disease. Sustainable – requires less natural resources.
It is not “all or nothing”
