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bojan_bozovic
Član broj: 29028
Poruke: 3292
*.dynamic.sbb.rs.
Sajt: angelstudio.org
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Citat: Vasastajić:
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Grešiš i to jako.
Jedina prava hrana za mozak su masnoće, odnosno holesterin koji sintetizuje jetra.
Šećeri, pogotovu rafinisani, a bogami ni ostali, ne trebaju ti ni u starim cipelama, pogotovu u količinama kojih nisi ni svestan da koristiš.
Samo jedan lagani primer, učio si još u školi da pomorandža sadrži veći procenat C vitamina od limuna, pa šta misliš zašto ga organizam lakše koristi iz limuna.
Odgovor je jednostavan, molekulska struktura C vitamina i šećera su gotovo identične, pa ih organizam gotovo i ne razlikuje, a bivajući stalno "gladan"energije, pre će se okrenuti šećeru nego C vitaminu, a bez C vitamina nema sinteze kolagena, bez kolagena nema regeneracije mekih tkiva u organizmu.
U meka tkiva spadaju i krvni sudovi, pa ti sada vidi.
Sa http://www.acnp.org/
http://www.acnp.org/g4/gn401000064/ch064.html
Citat: P. J. Magistretti, L. Pellerin, and J.-L. Martin: Institut de Physiologie, Faculté de Médecine, Université de Lausanne, CH 1005 Lausanne, Switzerland
Glucose is the obligatory energy substrate for brain and it is almost entirely oxidized to CO2 and H2O. This simple statement summarizes, with few exceptions, over four decades of careful studies of brain energy metabolism at the organ and regional levels, extensively reviewed elsewhere (e.g., 10, 60, 61). To reflect the focus of this book, and to include recent observations made in several laboratories including our own, we provide in this chapter a key for reinterpreting brain energy metabolism with a cellular perspective. This key relies primarily on the cytological relationships and chemical interactions among the various cell types of the brain. The view that emerges from this cellular and molecular analysis is a cell-specific sequence of processes that eventually leads to the almost complete oxidation by the brain of blood-borne glucose, which is in accordance with the introductory statement. The proposed model relies on already available data; it can further be tested experimentally, and it provides an explanation for some recent unexpected data obtained by positron emission tomography (PET) and functional magnetic resonance imaging (MRI) studies in humans (14, 40, 49).
ENERGY METABOLISM AT THE ORGAN LEVEL
Although the brain represents only 2% of the body weight, it receives 15% of the cardiac output, 20% of total body oxygen consumption, and 25% of total body glucose utilization. With a global blood flow of 57 ml/100 g·min, the brain extracts approximately 50% of oxygen and 10% of glucose from the arterial blood. Hence, the glucose utilization of the brain, as assessed by measuring the arterial–venous difference (22), is 31 mmol/100 g·min. Oxygen consumption is 160 mmol/100 g·min; because CO2 production is almost identical, the respiratory quotient (RQ) of the brain is nearly 1, indicating that carbohydrates are the substrates for oxidative metabolism (60). Given a theoretical stoichiometry of 6 mmol of oxygen consumed for each mmole of glucose, glucose utilization by the brain should in theory be 26.6 mmol/100 g·min. As indicated earlier, the measured glucose utilization is 31 mmol/100 g·min, indicating that an excess of 4.4 mmol/100 g·min of glucose follows other metabolic fates. Glucose can produce metabolic intermediates, such as lactate and pyruvate, which do not enter necessarily in the tricarboxylic acid cycle but rather can be released and removed by the circulation. Glucose can be incorporated into lipids, proteins, and glycogen, and it is also the precursor of certain neurotransmitters such as g-aminobutyric acid (GABA), glutamate, and acetylcholine (10, 60).
Numerous studies have been performed to identify molecules that could substitute for glucose as an alternative substrate for brain energy metabolism. Among the vast array of molecules tested, mannose is the only one that can sustain normal brain function in the absence of glucose (59). Mannose crosses the blood–brain barrier and in two enzymatic steps is converted to fructose-6-phosphate, a physiological intermediate of the glycolytic pathway. However, mannose is not normally present in the blood and cannot therefore be considered a physiological substrate for brain energy metabolism. Lactate and pyruvate can sustain synaptic activity in vitro (36, 55). Because of their limited permeability across the blood–brain barrier, they cannot substitute for plasma glucose to maintain brain function (43). However, if formed inside the brain parenchyma, they are useful metabolic substrates for neural cells (66). Under particular conditions, such as starvation, diabetes, or in breast-fed neonates, plasma levels of the ketone bodies acetoacetate and D-3-hydroxybutyrate increase markedly (41). Under these conditions, acetoacetate and D-3-hydroxybutyrate can be used by the brain as metabolic substrates (41).
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Re: Zdrava hrana - ljudi dal` je ovako i u Svetu ili moze samo kod nas?