influence of fats and oils in evolutionary aspects of...
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Influence of Fats and Oils in Evolutionary
Aspects of Humanity.
“Fats made us humans”
José Enrique Campillo Álvarez.
University of Extremadura, Spain
There are two importants facts about
lipids:
1.Lipids are the least understood of the
biomolecules.
Compared with polynucleotides (DNA, RNA), proteins, organic acids,
or sugars, lipids remain a poorly described and a perplexing black box.
J.B. German. Maternal and Child Nutrition; 2011
2. Lípids are related with the so-called
diseases of affluence.
Inflamatory and autoinmune disorders, metabolic syndrome, obesity,
atherosclerosis and cardiovascular disease, mental and psychiatric
diseases.
C.E.Ramsden. British Journal of Nutrition; 2010
Missing the forest for the trees?
Cunnane S.C. British Journal of Nutrition; 2007
Why is it so difficult to elucidate the biological
role of lipids and their contribution to major
diseases affecting us today in developed
societies?
Evolutionary or darwinian medicine
Many contemporary diseases:
Oxford University Press, 1999
Incompatibility between the lifestyles and environments in
which human currently live, and the condition under which
human biology evolved.
In the last century, major changes have been taken
place in our diet, particularly in the type and amount
of fats and in the antioxidant content of foods.
The fats have played an important role in adaptation
to various adverse circumstances during human
evolution.
The lipid discrepancies
Simopoulus A.P. Mol Neurobiol; 2011.
Drought.
Savannas and
shrub steppes.
More drought and
brain growth.
The Neolithic
Revolution.
Nutritional main stages in the evolution of
the human species
Warm and
humid jungle of
final Miocene.
8 4 2 0.02Million years b.p.
Large bowel fermentative
Fruits leaves stems roots
The main nutrients were fructose and complex polysaccharides.
Furthermore, some proteins and very little fats.
First stage: the end of the Miocene.
FRUCTOSE
TG
TG hepatic
TG-VLDL Fatty
deposits
FA GP
Tappy L., Physiol Rev, 2010
Fructose metabolism differs markedly from that of
glucose due to its almost complete hepatic extraction
and rapid hepatic conversion into lactate and fat.
Johnson R.J., Am J Clin Nutr, 2007
Year
Prevalence of
obesity (%)
Sugar consumption
(kg / person / year)
Sugars are the foods that produce more
fat in the body.
tolerance limit
Data from United Kingdom and U.S.A.
Fructose abuse in developed societies.
10 m.y. b.p.
The ability to convert
the fructose into fat
that allowed our
ancestors to evolve.
The monosaccharide that is
consumed most in the developed
world is the FRUCTOSE
Today it causes obesity
and related diseases such
as diabetes and metabolic
syndrome.
five million years ago, geological
and climatic changes caused the
beginning of a great drought in
East Africa.
Second stage: the life in the shrub
savanna of Pliocene.
Food: Roots, berries, fruits, stems, leaves,
insects, rodents, reptiles, carrion.
Food poor, with long periods of fasting.
Long periods of starvations.
TRIFTY GENOTYPE
Gene mutations
Metabolic changes
THE OBESE
APE
J.V. Neel: The thrifty genotype, 1962
Humans are one
of the animals
with the highest
percentage of fat
The thrifty genotype
The thrifty genotype
1. In 2002, it was described the first nine thrifty loci and theirfunction in producing obesity.
Kagawa Y: BBRC, 2002
2. In 2010 it was published an association analyses of
249,796 individuals reveal eighteen new loci associated
with body mass index.
-It was confirmed the 14 known loci.
-It was described 18 new loci.
-The thrifty genes showed a Gaussian distribution in
the population.
Elizabeth K. Speliotes. Nat. Genet, 2010
Low High
ALWAYS ARE THIN
ALWAYS ARE OBESE
DEPENDENCE OF ENVIRONMENTAL FACTORS
ENVIRONMENT
GENES
The thrifty genes cause obesity in societies
where abundance is constant.
Amount of thrifty loci
Third stage: more drought and
brain growth.
Turkana boy, 1,8 m.y.b.p.
1.More difficult to find food.
2.Adaptation to eating animal food.
3.Change in the type of dietary fat.
The genus Homo
300
600
900
1200
1500
02 134567
Million years before present
Chimpanzee
Ardipithecus
ramidus
Autralopithecus
H. habilis
H. erectus
H. heilderbergensis
H. sapiens
Cranial capacity (cc)Evolution of human brain
Schoenemann. Ann rev Anthropol, 2006
To move from one brain of 400 cc to
another of 1400 required two essential
conditions:
1.- Provide the necessary energy:
Because the ongoing increase in human brain it became the most
metabolically energy-expensive organ in the human body, consuming
20–25% of the adult and 70–75% of the newborn metabolic budget.
Ben-Dor M, PLoS ONE, 2011.
2.- Provide the necessary bricks:
The brain requires large amounts of polyunsaturated fats,
especially DHA.
Crawford M.A. Nutr Health. 2012
Because the metabolic ceiling on protein intake
and the energetic ceilling on plant food intake,
how could our ancestors provide for the brain
caloric requirements?
The answer may lie in the obligatory
consumption of animal fat.
Ben-Dor M, PLoS ONE, 2011.
Relative gut volume %
stomach
Aiello L.C. Ann Rev Anthopol. 2002
small
intestine
colon
human
chimpacee
The more compact, the human gut is less efficient at extracting
sufficient energy and nutrition from fibrous foods and considerably
more dependent on higher-density bioavailable foods.
1.The brain is a lipid dense organ, second only to adipose tissue.
60% of the dry weight of the brain consists of
polyunsaturated fatty acids- phospholipids.
2. The ω-3 DHA has been identified as the most important fatty
acid of functional significance in the brain.
3. Published estimation of the total amount of DHA in the human
brain was 5g.
Approximately 1,3 % of the dry weight.
Bradbury J. Nutrients, 2011
Animal fat could also be a very efficient source of the brics
required for brain construction.
Fat diet made us smart
Two circumstances allowed our ancestors
to obtain the necessary polyunsaturated
fat:
1.Physiological circunstances
2.Geological circunstances
1. The physiological circunstances
One solution was scavenging that was relatively easy
and gave them food rich in ω-3 PUFA.
1. Bone marrow of large herbivores
2. Brains
Both could be extracted with rudimentary stone tools.
physical
weakness
lack of effective
weapons
Hunting was very difficult
Blumenschine R.J. Sci. Am., 1992.
2. The geological circumstances
The acuatic ape
Large shallow lakes
with an abundance
of life
The ocean coast
E. Morgan. The Acuatic Ape. 1982.
ARACHIDONIC ACIDEICOSAPENTAENOIC ACID
CYCLOOXYGENASE
5 LIPOXYGENASELEUKOTRIENES LTA5LEUKOTRIENES LTA4
Paleolithic balance: ω-6 / ω-3 = 1
Protectins
ResolvinsDOCOSANOIDS
LINOLEIC ACID LINOLENIC ACID
Meat, liver, bone marrow, brain, eggs,
fish, shellfish, plants, green leafy
vegetables fruits, nuts and berries.
PROSTAGLANDINS PGE2
THROMBOXANE TXA2
PROSTACYCLIN PGI2
PROSTAGLANDINS PGE3
THROMBOXANE TXA3
PROSTACYCLIN PGE3
Simopoulos A.P. Mol Neurobiol. 2011; Crawford M.A. Nutr Health. 2012
Fourth stage: the neolithic revolution
the start of the ω-6 / ω-3 disbalance
AGRICULTURE
Cereals
Legumes
LIVESTOCK
Saturated Fat
Grain-fed beef
Dairy
CERAMICS, CRAFTS
Cooked
Vegetal oils
Alcohol
Bread and sweets
Salt
Cordain L. Eur J Clin Nutr, 2002.
The competition problem of elongation and
desaturation of ω-6 and ω-3 PUFA
LINOLEIC ACID
LA C18:2 N-6
LINOLENIC ACID
ALA C18:3 N-3
ARACHIDONIC
ACID AA C20:4 N-6
EICOSAPENTAENOIC ACID
EPA C20:5 N-3
Δ4 DESATURASE
ELONGASE
DOCOSAHESAENOIC ACID
DHA C22:6 N3
The same enzyme systems
are used for both, resulting
competition.
Δ6 Y Δ5
DESATURASES
ELONGASE
Crawford M.A. Nutr Health. 2012
The ω-6 / ω-3 disbalance was dramatically
increased in the last century.
ω-6 / ω-3 = 16
Meat and eggs
raised on grains.
Few fish
and marine
products.
Butter, margarine
and manufactured
foods.Seed oils: corn,
sunflower,
soybean,
safflower.
Excess fructose,
sweets, syrups,
sweetened drinks.
Few fruits and
vegetables.
ARACHIDONIC ACIDEICOSAPENTAENOIC ACID
CYCLOOXYGENASE
5 LIPOXYGENASELEUKOTRIENES LTA5LEUKOTRIENES LTA4
Protectins
ResolvinsDOCOSANOIDS
LINOLEIC ACID LINOLENIC ACID
PROSTAGLANDINS PGE2
THROMBOXANE TXA2
PROSTACYCLIN PGI2
PROSTAGLANDINS PGE3
THROMBOXANE TXA3
PROSTACYCLIN PGE3
Simopoulos A.P. Mol Neurobiol. 2011; Crawford M.A. Nutr Health. 2012
Today: increase of pro inflamatory and pro
atherosclerotic conditions and the prevalence of
opulence diseases and mental disorders.
Conclusions
Affluent societies are caught in a mismatch
between our evolutionary design and the actual
lifestyle.
With respect to the lipids should be noted three dangerous defects:
1.Fructose excess that becomes fat.
2.Excess of energy intake that thrifty genes stored as fat in the
adipose tissue.
3.Excess of intake of saturate, trans and ω - 6 fats and a reduction of
intake of ω – 3 fats.
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THANKS FOR YOUR ATENTION!
We should try to harmonize our Stone Age
genes with our way of life in the Space Age.