Omnivores Dilemma,
by Michael Pollan
“Our eating also constitutes a
relationship with dozens of other
species – plants, animals and fungi –
with which we have co-evolved to the
point where our fates are deeply
entwined,” (pg 10).
Pollan writes:
• About 1/5th of our meals are eaten
in cars, and 1/3rd of children eat
fast foods daily.
• What is our food chain? Huntergatherer, organic or industrial?
• “What am I eating? Where in the
world did it come from?” (17).
Energy: Sun to Plants to Sugar
Energy: Sun to Plants to Sugars
CARBOHYDRATES
SUGARS = Fuel for cells
ALCOHOLS = sugars with an -OH
STARCH = plant energy storage
CELLULOSE = plant structure +
support
• GLYCOGEN = short term animal
energy storage
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What are these things?
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Mono, di, triglycerides
Trans fats
TBHQ
Maltose
High fructose corn syrup (HFCS)
Xanthan gum
Lecithin
Ascorbic acid
Lactic acid
Xanthan gum =
Carbohydrate
http://en.wikipedia.org/wiki/Xanthan_gum
• Xanthan gum is a polysaccharide, derived from the
bacterial coat of Xanthomonas campestris, used as
a food additive andrheology modifier,[2] commonly
used as a food thickening agent (in salad dressings, for
example) and a stabilizer (in cosmetic products, for
example, to prevent ingredients from separating). It is
produced by the fermentation of glucose, sucrose,
or lactoseby the Xanthomonas campestris bacterium.
Maltose is a malt sugar, a
disaccharide
High Fructose Corn Syrup is about 50%
Fructose + 50% Glucose
CARBOHYDRATES = C+H
Fructose is the sweetest refined sweetner
Estimated intakes of total fructose (•), free fructose (▴), and high-fructose corn
syrup (HFCS, ♦) in relation to trends in the prevalence of overweight (▪) and
obesity (x) in the United States.
Bray G A et al. Am J Clin Nutr 2004;79:537-543
©2004 by American Society for Nutrition
Alpha amylase + Glucose isomerase
• Enzyme include Alpha amylase to break up the
starch, and glucose isomerase, which led to the
commercialization of high fructose corn syrups.
http://www.elmhurst.edu/~chm/vchembook/548HFsyrup.html
high-fructose corn syrup
• Consumption of high-fructose corn syrup in
beverages may play a role in the epidemic of
obesity American Journal of Clinical Nutrition, 2004
http://www.ajcn.org/content/79/4/537.short
• The digestion, absorption, and metabolism of
fructose differ from those of glucose. Unlike
glucose, fructose does not stimulate insulin
secretion.
• Because insulin acts as key signals in the regulation
of food intake and body weight, this suggests that
dietary fructose may contribute to increased energy
intake and weight gain.
What are Lipids?
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Lipids are Fats, Oils, Waxes, Steroids
FATS are : Glycerol + 3 Fatty Acids
Lipids are HYDROPHOBIC
Not very soluble (dissolvable) in water
Three types: (generally)
• Triglycerides – energy storage
• Phospholipids -membranes
• Sterols - hormones
LIPIDS !
• Mono, di, triglycerides
• Lecithin
• Trans fats
Monoglyceride
FATS = an alcohol + carbon chain
Triglyceride
Lecithin – a lipid
• Lecithin is a major structural component of
biological membranes1,2. Lecithin + related
phospholipids form as bilayer structures where
the hydrophilic head groups are orientated
towards the watery surface and the
hydrophobic hydrocarbon chains towards the
inside. http://www.nature.com/nature/journal/v281/n5731/abs/281499a0.html
PhosphoLipids =
Carbon
Chains +
Phosphate
Heads
• The fatty acids of unsaturated fats
(plant oils) contain double bonds
– These prevent them from solidifying at room
temperature
• Saturated fats (lard) lack double bonds
– They are solid at room temperature
Figure 3.8C
SATURATION OF FATTY ACIDS
Tertiary butylhydroquinone, or TBHQ
• Stabilization of Nrf2 by tBHQ Confers Protection against Oxidative
Stress-Induced Cell Death in Human Neural Stem Cells
http://toxsci.oxfordjournals.org/content/83/2/313.short
• The present study is aimed to determine whether increased protein
stability is a mechanism by which quinone compounds, like tertbutylhydroquinone (tBHQ), may enhance Nrf2-mediated
transcriptional activation and subsequent antioxidant protection.
The food additive butylated hydroxyanisole
(BHA) has been shown to induce gastrointestinal
hyperplasia in rodents by an unknown
mechanism. We therefore analysed the effect of
BHA and its primary metabolites tertbutylhydroquinone (TBHQ) and tertbutylquinone (TBQ) on 8-oxo-deoxyguanosine
formation and labelling indices in human
lymphocytes in vitro. http://carcin.oxfordjournals.org/content/16/3/507
Plant
Stomata
open +
close for
gas
exchange,
but also
lose
water this
way.
Problem with C3 Photosynthesis
• Photorespiration in C3
plants:
– When its hot out, stomata
close up…why is this a
problem? CO2 can’t get into
cell and O2 can’t leave
– O2 then enters Calvin Cycle
– Sugar production stops
because there’s no carbon
source
C4 plants also photosynthesize “better”
with stomates closed and reduce water
losses in leaves.
The C4 photosynthetic plants also take in
more Carbon-13 isotopes.
Corn, or maize
(Zea mays), was
domesticated
from a wild grass
called Teosinte
about 6300 years
ago in Mexico.
Hybrid Corn Yields
• 1920’s 20 bushels/ acre
• 1930’s first hybrids
• 1950’s 75 bushels/acre
• Now 180 bushels/acre
YieldGard VT Triple
YieldGard VT Triple®: the stacked trait with
enhanced hybrid performance
https://www.dekalb.ca/Eastern/en-CA/Products/Corn/Traits/Pages/YieldGardVTTriple.aspx
According to the invention, a hybrid maize plant,
designated as 34H31, are produced by crossing two
Pioneer Hi-Bred International, Inc. proprietary inbred
maize lines.
This invention relates to the hybrid seed 34H31, the
hybrid plant produced from the seed, and variants,
mutants, and trivial modifications of hybrid 34H31
http://www.patentstorm.us/patents/6897360.html
Nitrogen fixation
• The Haber process, also called the Haber–Bosch
process, is the nitrogen fixation reaction
of nitrogen gas and hydrogen gas, over an
catalyst, which is used to industrially
produce ammonia. http://en.wikipedia.org/wiki/Haber_process
• It is estimated that half of the protein within
human beings is made of nitrogen that was
originally fixed by this process, the remainder
was produced by nitrogen fixing bacteria and
archaea.
Bovine spongiform
encephalopathy
• Epidemiological studies showed the vehicle of
infection to be meat and bone meal that had
been incorporated into concentrated
feedstuffs as a protein-rich supplement.
• The outbreak was probably started by scrapie
infection of cattle, but the epidemic was
driven by the recycling of infected cattle
material within the cattle population
http://faorlc.cgnet.com/es/prioridades/transfron/eeb/pdf/bse.pdf
BSE (Bovine Spongiform
Encephalopathy, or Mad Cow Disease)
• BSE (bovine spongiform encephalopathy) is a
nervous system disorder of cattle from an infection
by an protein called a prion.
• The nature of the transmissible agent is not well
understood. For reasons that are not yet
understood, the normal prion protein changes into
a pathogenic (harmful) form that then damages the
central nervous system of cattle.
http://www.cdc.gov/ncidod/dvrd/bse/