What are the effects of fats ( saturated and unsaturated ), proteins and carbohydrates on the sensitivity of the cells to Insulin and other ligands that control cell activity?
First, let us see the recent researches that are connected to this aspect:
# At Rutgers University, Dept of Nutrition, Researchers found that fish oil- fed animals- have greater stimulation of the Glucagon stimulated adenylate-cyclase ( Glucagon is a hormone that raises blood glucose, and adenylate-
cyclase is its responsive enzyme). They found the stimulation is less in corn oil- fed animals, they found also that Butter fat- and all cholesterol supplemented group- fed animals show a depression in Glucagon-adenylate cyclase- stimulation. In other words, fish oil and corn oil increased blood glucose and Butter fat and cholesterol
supplements decreased blood glucose in this specific experiment.
#R.S.MacDonald and W.H.Thornton Jr. found that dietary fat composition has been shown to alter the plasma membrane lipid composition of adipocytes, muscles and other tissues. These changes in membrane lipid composition have been correlated with altered Insulin receptors binding and signal transduction( across the cell membrane).
#As is written in Medical Journal of Australia(e MJA), the functionality of proteins in the membrane is dependent on membrane fluidity ( which was found to decrease with age leading to a stiff membrane as S.M.Harman M.D. showed), especially when the proteins have to collide with other molecules to exert their effects (as in case of Insulin effect).
#Surveys in some Asian islands revealed that inhabitants never knew overweight, diabetes and cardiovascular
diseases while eating grains, vegetables,fruits and coconut oil until they changed their nutritional style to eating
the modern rich diet composed of meat, refined flour and the new wave oils, when they were found to have high incidence of cardiovascular diseases, obesity and diabetes ( 1 out of 2 is diabetic).
Before we lead ourselves to certain conclusions of these scientific findings, let us first recognize the Insulin and other ligands ( molecules that bind a receptor to exert its effects, like hormones) receptors and their surrounding environment.
Cell membranes are designed to act like a boundaries between the cell and its surrounding environment. Both the cell and its surrounding environment are composed mainly of water, then the membrane should not be water soluble, and the material that fulfils this crucial function is phospholipids which is neither water soluble nor lipid soluble at its concentration in the membrane ( to keep an intact membrane and not a detached one).
The phospholipid molecule is present in edible fats in small concentrations (except egg yolk). It is a derivative of TriAcylGlycerol ( triglycerides) ,the main component of fats, and is composed of a molecule of Glycerol attached to 3 molecules of fatty acids and is not charged. But phospholipids has an electrically charged part attached to one of the fatty acids in a triglyceride molecule, this charged part acts like a polar head that is entailing a bi-forked uncharged tail composed of the remaining 2 fatty acids. An electric charge in a molecule increases its solubility in water.
The fluidity of membrane depends on the nature of the tail of a phospholipid molecule ( the 2 molecules of fatty acids in that molecule) when they are saturated fatty acids ( present abundantly in coconut and palm kernel oils), then they are closer to each other making a denser membrane, but when one of them is mono- or
poly-unsaturated fatty acid, then the part bearing a double-bond acquires coils acquiring the shape of the letter S when bearing 2 double bonds or half the latter S when bearing one double-bond.This bend or -kink- in the molecule shortens the molecule and causes a change in the electrical affinity of the adjacent molecule at the same time, leading to more spaces between them.
Cell membranes are composed of 2 layers of phospholipids having the polar multi-head part in the outer most and innermost surfaces facing blood and cytoplasm respectively ( both are composed mainly o water ). The non-polar tails of phospholipid molecules are included between the 2 polar surfaces, and they represent the matrix of the membrane. The nature of a phospholipid layer is determined in part by the lipid matrix of the membrane ( Diet ) and its polar heads part ( genetically ).
Embedded in these 2 layers of phospholipid are Protein molecules, which act like locks on the membrane and open the cells for import or export of metabolites (products of metabolism, like sugars, amino acids,fatty acids, electrolytes....etc). The keys of these locks are either hormones or neurotransmitters ( the end product of a nerve impulse or signal ).
The receptors or locks on the cell membrane are arranged within the cell membrane in such a way to expose its functional part with a spacial configuration that has a geometrical design and electric affinity to specifically fit a specific ligand ( hormone or neurotransmitter). Any change in the position of the displayed functional part of a receptor (lock) may change the response of this receptor to its specific key ligand, with an attenuated, impaired or abolished response.
We cannot derive any solid conclusions from these results, because scientific facts cannot be based on speculations or conventional wisdom, there should be a design of many experiments that lead to an approved conclusion leading to a specific recommendations. It is a premature time to throw accusations on this side or that side.
For you and me as folks reading these published findings, we can think about what we have in hands now of solid facts. We should eat polyunsaturated fats to supply us the Essential Fatty Acids, and we can now think about using the saturated fats when our food should be exposed to high temperature to minimize the production of Trans-Fats.
Living with Type II Diabetes?
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Atkins "Nightmare" Diet
When Dr. Atkins Diet Revolution was first published, the President of the American College of Nutrition said, "Of all the bizarre diets that have been proposed in the last 50 years, this is the most dangerous to the public if followed for any length of time."[1]
When the chief health officer for the State of Maryland,[2] was asked "What's wrong with the Atkins Diet?" He replied "What's wrong with... taking an overdose of sleeping pills? You are placing your body in jeopardy." He continued "Although you can lose weight on these nutritionally unsound diets, you do so at the risk of your health and even your life."[3]
The Chair of Harvard's nutrition department went on record before a 1973 U.S. Senate Select Committee investigating fad diets: "The Atkins Diet is nonsense... Any book that recommends unlimited amounts of meat, butter, and eggs, as this one does, in my opinion is dangerous. The author who makes the suggestion is guilty of malpractice."[4]
The Chair of the American Medical Association's Council on Food and Nutrition testified before the Senate Subcommittee as to why the AMA felt they had to formally publish an official condemnation of the Atkins Diet: "A careful scientific appraisal was carried out by several council and staff members, aided by outside consultants. It became apparent that the [Atkins] diet as recommended poses a serious threat to health."[5]
The warnings from medical authorities continue to this day. "People need to wake up to the reality," former U.S. Surgeon General C. Everett Koop writes, that the Atkins Diet is "unhealthy and can be dangerous."[6]
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