Influence of Fats and Oils in Evolutionary Aspects of Humanity. Fats made us humans

Transcription

1 Influence of Fats and Oils in Evolutionary Aspects of Humanity. Fats made us humans José Enrique Campillo Álvarez. University of Extremadura, Spain

2 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; 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

3 Missing the forest for the trees? Why is it so difficult to elucidate the biological role of lipids and their contribution to major diseases affecting us today in developed societies? Cunnane S.C. British Journal of Nutrition; 2007

4 Evolutionary or darwinian medicine Oxford University Press, 1999 Many contemporary diseases: Incompatibility between the lifestyles and environments in which human currently live, and the condition under which human biology evolved.

5 The lipid discrepancies The fats have played an important role in adaptation to various adverse circumstances during human evolution. 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. Simopoulus A.P. Mol Neurobiol; 2011.

6 Nutritional main stages in the evolution of the human species Drought. Savannas and shrub steppes. More drought and brain growth. The Neolithic Revolution. Warm and humid jungle of final Miocene Million years b.p.

7 First stage: the end of the Miocene. Fruits leaves stems roots Large bowel fermentative The main nutrients were fructose and complex polysaccharides. Furthermore, some proteins and very little fats.

8 Fructose metabolism differs markedly from that of glucose due to its almost complete hepatic extraction and rapid hepatic conversion into lactate and fat. FRUCTOSE FA GP TG hepatic TG TG-VLDL Tappy L., Physiol Rev, 2010 Fatty deposits

9 Sugars are the foods that produce more fat in the body. Sugar consumption (kg / person / year) Prevalence of obesity (%) Data from United Kingdom and U.S.A. tolerance limit Johnson R.J., Am J Clin Nutr, 2007 Year

10 Fructose abuse in developed societies. The ability to convert the fructose into fat that allowed our ancestors to evolve. Today it causes obesity and related diseases such as diabetes and metabolic syndrome. 10 m.y. b.p. The monosaccharide that is consumed most in the developed world is the FRUCTOSE

11 Second stage: the life in the shrub savanna of Pliocene. five million years ago, geological and climatic changes caused the beginning of a great drought in East Africa. Food: Roots, berries, fruits, stems, leaves, insects, rodents, reptiles, carrion. Food poor, with long periods of fasting.

12 The thrifty genotype Long periods of starvations. Gene mutations Metabolic changes TRIFTY GENOTYPE Humans are one of the animals with the highest percentage of fat THE OBESE APE J.V. Neel: The thrifty genotype, 1962

13 The thrifty genotype 1. In 2002, it was described the first nine thrifty loci and their function in producing obesity. Kagawa Y: BBRC, 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

14 The thrifty genes cause obesity in societies where abundance is constant. DEPENDENCE OF ENVIRONMENTAL FACTORS ALWAYS ARE THIN ALWAYS ARE OBESE Low Amount of thrifty loci High ENVIRONMENT GENES

15 Third stage: more drought and brain growth. The genus Homo 1.More difficult to find food. 2.Adaptation to eating animal food. 3.Change in the type of dietary fat. Turkana boy, 1,8 m.y.b.p.

16 Evolution of human brain Cranial capacity (cc) Ardipithecus ramidus H. habilis Autralopithecus H. sapiens H. heilderbergensis H. erectus Chimpanzee Million years before present Schoenemann. Ann rev Anthropol, 2006

17 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, Provide the necessary bricks: The brain requires large amounts of polyunsaturated fats, especially DHA. Crawford M.A. Nutr Health. 2012

18 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.

19 Relative gut volume % human chimpacee stomach small intestine colon 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. Aiello L.C. Ann Rev Anthopol. 2002

20 Fat diet made us smart Animal fat could also be a very efficient source of the brics required for brain construction. 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

21 Two circumstances allowed our ancestors to obtain the necessary polyunsaturated fat: 1.Physiological circunstances 2.Geological circunstances

22 1. The physiological circunstances physical weakness lack of effective weapons 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 Hunting was very difficult Both could be extracted with rudimentary stone tools. Blumenschine R.J. Sci. Am., 1992.

23 2. The geological circumstances The acuatic ape Large shallow lakes with an abundance of life The ocean coast E. Morgan. The Acuatic Ape

24 Paleolithic balance: ω-6 / ω-3 = 1 Meat, liver, bone marrow, brain, eggs, fish, shellfish, plants, green leafy vegetables fruits, nuts and berries. LINOLEIC ACID ARACHIDONIC ACID PROSTAGLANDINS PGE2 THROMBOXANE TXA2 PROSTACYCLIN PGI2 CYCLOOXYGENASE LINOLENIC ACID EICOSAPENTAENOIC ACID PROSTAGLANDINS PGE3 THROMBOXANE TXA3 PROSTACYCLIN PGE3 LEUKOTRIENES LTA4 5 LIPOXYGENASE DOCOSANOIDS Protectins Resolvins LEUKOTRIENES LTA5 Simopoulos A.P. Mol Neurobiol. 2011; Crawford M.A. Nutr Health. 2012

25 Fourth stage: the neolithic revolution the start of the ω-6 / ω-3 disbalance AGRICULTURE LIVESTOCK Cereals Saturated Fat Legumes Grain-fed beef Dairy Cordain L. Eur J Clin Nutr, CERAMICS, CRAFTS Cooked Vegetal oils Alcohol Bread and sweets Salt

26 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 Δ6 Y Δ5 DESATURASES ELONGASE ARACHIDONIC ACID AA C20:4 N-6 EICOSAPENTAENOIC ACID EPA C20:5 N-3 Δ4 DESATURASE The same enzyme systems are used for both, resulting competition. ELONGASE DOCOSAHESAENOIC ACID DHA C22:6 N3 Crawford M.A. Nutr Health. 2012

27 The ω-6 / ω-3 disbalance was dramatically increased in the last century. 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. ω-6 / ω-3 = 16

28 Today: increase of pro inflamatory and pro atherosclerotic conditions and the prevalence of opulence diseases and mental disorders. LINOLEIC ACID ARACHIDONIC ACID PROSTAGLANDINS PGE2 THROMBOXANE TXA2 PROSTACYCLIN PGI2 CYCLOOXYGENASE LINOLENIC ACID EICOSAPENTAENOIC ACID PROSTAGLANDINS PGE3 THROMBOXANE TXA3 PROSTACYCLIN PGE3 LEUKOTRIENES LTA4 5 LIPOXYGENASE DOCOSANOIDS Protectins Resolvins LEUKOTRIENES LTA5 Simopoulos A.P. Mol Neurobiol. 2011; Crawford M.A. Nutr Health. 2012

29 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.

30 We should try to harmonize our Stone Age genes with our way of life in the Space Age. THANKS FOR YOUR ATENTION!