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אוטיזים, תזונה וחשיפה לשמש

כמעט כולם באמריקה (ובעולם) משוכנעים בשני העקרונות הבאים בנוגע לאיך לחיות חיים ארוכים ובריאים: הקפידו על תזונה דלת שומן, הימנעו מחשיפה לקרניים המזיקות של השמש. המטרה של ד"ר סטפני סנף במאמר הזה היא לשכנע אותך כי שני העקרונות הללו יחדיו, הם עצה רפואית גרועה וכי ההשלכות של ההצלחה בשיווק המלצה זו לציבור הן הרסניות וארוכות טווח , במיוחד לילדים . "למעשה, ניתן לשרטט עכשיו פרופיל נפשי של האם הטיפוסית לילד אוטיסט: היא תהיה אשה המקפידה מאוד לגבי הימנעות ממזונות עשירים בשומן, היא תעמוד על המשמר להגן על עצמה מפני הקרניים המזיקות של השמש בכל פעם שהיא יוצאת מהבית. כמו כן היא תקפיד להישאר רזה כעיפרון ולשמור על עצמה בכושר גופני. בקיצור, עבור רוב האמריקנים, היא תהיה ההתגלמות של בריאות טובה."

The Two Factors That Elevate Your Risk for an Autistic Child By Dr. Stephanie Seneff Just about everyone in America is convinced of two well-established tenets for how to live a long and healthy life: • Eat a low-fat diet • Avoid the damaging rays of the sun My goal in this essay is to convince you that these two tenets, taken together, are extremely bad medical advice, and that the consequences of our government`s success in selling this well-intended but misguided recommendation to the American public are devastating and long-lasting, particularly to our nation`s children. In fact, I have now formed a mental profile of the prototypical mother of an autistic child: she would be a woman who is extremely conscientious about avoiding foods that are high in fat content, she would be very vigilant to protect herself from the harmful rays of the sun whenever she ventures outside, and she would be very careful to stay pencil thin and to keep herself physically fit. In short, to most Americans, she would be the epitome of good health.

How Diet and Sun Exposure May Impact Your Chances of Having Autistic Child

The onset of menstruation will not occur until the body fat content rises above 17 percent. Young female athletes often find that menstruation is delayed, or that their menstrual periods are suddenly shut down, likely because their exercise has upset the ratio of muscle to fat to the point where Mother Nature considers it a bad bet to risk a pregnancy. Ballet dancers and gymnasts, who must stay thin but still be very strong, are at great risk of having their menstrual cycles shut down completely [1]. Human biology wants fat not just on the person, but also in the diet, if a pregnancy is in the wings. This fact has been proven quite conclusively by a recent analysis of data from the Nurses` Health Study, an ambitious long-term study involving over 18,000 nurses, which has yielded a wealth of data on issues related to women`s health. Dr. Jorge Chavarro at the Harvard School of Public Health analyzed data on their dietary practices over an eight year period, and looked for correlations with various health issues ( Dairy Fat Fertility). Of all the dietary associations that were investigated, the one associating fat in dairy consumption with fertility gave the most striking and statistically significant results. Women who said they ate low-fat diary (e.g., skim milk and low-fat yogurt) increased their risk of infertility by 85 percent, whereas women who consistently ate high-fat dairy (whole milk and ice cream) decreased their risk by 27 percent [2]. Consider this: chicken eggs are now considered "unhealthy" due to their high concentration of cholesterol. They are also one of the best food sources of vitamin D. This is to say, a mother hen supplies her unborn chick with nutritional supplements that include a rich supply of cholesterol and a rich supply of vitamin D. Cow`s milk is also high in fat, unless it`s been manipulated into skim milk, and would be high in natural vitamin D if it weren`t pasteurized (the high temperature destroys the vitamin D). We now artificially restore synthetic vitamin D to replace what`s been destroyed by pasteurization, a process that can`t work well with skim milk, since vitamin D is only soluble in fat, and there is none. We can conclude that a mother cow loads up the milk she feeds to her newborn calf with fats and vitamin D. Even fish supply their offspring with plenty of vitamin D and cholesterol, as evidenced by the fact that caviar (fish eggs) is high in fat and a good source of vitamin D. Human milk has an even higher fat content than cow`s milk; 55 percent of the calories in breast milk are from fat. It would also be loaded with vitamin D if the mother had not aggressively protected herself from the "damaging" rays of the sun. Mother Nature considers it important for newborns, whether chicks or calves or fish or human infants, to be well supplied with fats and vitamin D, in order to assure healthy development. The most crucial role for both vitamin D and cholesterol in the embryo is in the development of the brain and central nervous system. The human brain makes up only 2 percent of the body`s weight, but it contains nearly 25 percent of its total cholesterol [3], so it`s easy to imagine that the supply chain had better be loaded with cholesterol. One of the critical things that happens during the development of the embryonic brain is the growth of millions of nerve fibers or "axons" to form connections among all the neurons in the developing brain. These axons are coated with a thick fatty substance called the myelin sheath, which provides insulation that keeps the signal intact and allows for fast and long-distance transport with minimal loss. This myelin sheath has very high cholesterol content — higher than that of any other brain tissue. According to Ursula Dicke and Gerhard Roth [4], it is the extra length and extra thickness of the myelin sheaths around the nerve fibers of the human brain that most clearly differentiates it from the brains of other mammals. While we do also have more cortical neurons, the difference in their counts between humans and elephants and whales is only about 5 percent, not enough to account for the observed distinct differences in intelligence. Thus, humans uniquely need even more fat in the baby`s milk for a good reason: the infant needs to grow substantially more, longer, and thicker myelin sheaths than any other animal.

Cholesterol and Vitamin D: A Brief Introduction

Everybody in America thinks they know what cholesterol is: it`s that bad stuff that gums up all your arteries and leads to sudden death by heart attack. If you have too much in your blood, you should be very worried. The argument is then that, to lower the level, you need to adopt a low-fat diet. If that doesn`t work, you`ll have no choice but to start taking a cholesterol-lowering drug like Lipitor. There is actually only a weak correlation between high cholesterol and heart disease. Many people with high cholesterol never get heart disease, and, conversely, many people with heart disease have low cholesterol levels. And the ever-so-popular statin drugs lead to many disturbing side effects that should convince the informed reader that they can`t possibly be good for you [5] . Vitamin D is also familiar as the "sunshine" vitamin: most people remember the story about 19th Century Great Britain and the rickets epidemic, brilliantly solved by the realization that rickets is a consequence of vitamin D deficiency, a problem which can easily be solved by getting out in the sun. Recently, researchers are finding out more and more critical roles that vitamin D plays, far beyond strengthening the bones, in diverse systems throughout your body. One thing most people may not realize is that vitamin D and cholesterol are chemically almost indistinguishable. Vitamin D is manufactured in your body from cholesterol, specifically, from 7-dehydrocholesterol, through a very small change in chemical structure (which involves dropping a single hydrogen molecule) [6] . This happens in the skin, and only happens if a catalyst in the form of ultraviolet rays from the sun, is present. If you`re wearing a sunscreen with an SPF level of 8 or greater, then you`re pretty much guaranteeing that you won`t generate any vitamin D. Furthermore, cholesterol is the predecessor to a host of other factors that your body uses as catalysts for all kinds of biological processes. For example, testosterone, the male hormone. And cortisol, a hormone produced by the adrenal glands that plays a critical role in managing stress. Furthermore, the myth that high cholesterol is bad is not borne out by the facts. In 1990, researchers from 19 studies worldwide met in Bethesda, Md, to compare results on cholesterol studies, and produced plots summarizing their conclusions ([7], p. 81). For women, there is, over the entire curve, an inverse correlation between cholesterol levels and mortality rates. That`s right: the lower the cholesterol reading, the more likely she is to die. It is true that men with very high cholesterol (> 240 mg/dl) have an increase in mortality due to an increased incidence of heart disease; however, mortality increases on the low side as well (below 160 mg/dl), due to increased risk of cancer and respiratory and digestive diseases. This means that both men and women have higher mortality if their cholesterol levels are too low. Women should worry only about low cholesterol, never about high cholesterol.

The Horrendous Dangers of Statins During Pregnancy

But my concern is not so much about the longevity of the adult, but rather the health of the unborn child; specifically, the unborn child whose mother conscientiously adheres to the regimens of a low-fat diet and sun avoidance. If her cholesterol levels are high, she will likely lament that fact. But one thing she should not do, if she`s planning on having a child, is take a statin drug like Lipitor to lower her cholesterol readings. The reason is simple, although not widely advertised by the drug industry: Statin drugs will with high probability render her unborn child non-viable. Researchers at the U.S. National Institutes of Health found severe abnormalities in the central nervous system, as well as limb deformities, in nearly 40 percent of the babies in a study of women who took statins during the first trimester of pregnancy [8] . Statins are labeled as a category X drug with respect to pregnancy by the Food and Drug Administration, the same category as that given to Thalidomide. If you are above a certain age, you will remember this infamous drug that swept Europe by storm in the 1950`s. Widespread use of Thalidomide led to an epidemic of infants being born without arms; without legs; without ears; deaf. They eventually traced the source to the new wonder drug that was supposed to be a calming tranquilizer with essentially no side effects. A pregnant woman who takes Thalidomide between the 4th and 7th week of her pregnancy has a 20 percent or greater risk of producing a baby that is missing significant body parts. But at least these children were mentally sound. Their brains were generally fine, and they grew up to have normal intelligence, which allowed them to lead productive lives. The effects of statin drugs are so potent that there`s little hope for survival, let alone anything resembling a normal life. This outcome is due to the disruption of a critical step in a biological pathway that leads to the production of cholesterol, an essential building block of the nervous system. A serious disorder known as ("Smith-Lemli-Opitz") " syndrome (SLOS) is characterized by a genetic defect resulting in an inability to synthesize adequate cholesterol. Most fetuses that are unfortunate to be conceived with this genetic defect don`t make it to 16 weeks of gestation before the pregnancy ends in a miscarriage. If they do manage to make it to term, they typically suffer from major brain defects, resulting in autism or other forms of mental retardation [9].

The Roles of Cholesterol and Vitamin D in Your Brain

As I`ve already mentioned, your brain is characterized by an overabundance of well-conditioned nerve fibers. All of these fibers are coated with a fatty myelin sheath that is critical to their ability to carry a signal from one neuron to another one, especially one that is some distance away. The human infant must construct this marvel of nature from raw materials it obtains from the mother`s supply chain. Not only is cholesterol a core building block of the brain, but also vitamin D plays a critical although not well-understood role in brain development. Researchers at the University of Queensland in Australia have studied brain development in embryonic rat brains in order to assess whether low maternal vitamin D might affect brain development [11]. First of all, the vitamin D receptor (VDR) is prevalent in your brain cells, a clear indicator that vitamin D plays some role (Vitamin D in Nervous System). These researchers determined that the VDR appeared simultaneously with the well-described stage when there is an increase in apoptotic cells and decrease in mitotic cells during brain development. Apoptosis is a natural process that programs the cell to die; mitosis is the process of splitting to become two cells instead of one. Thus, these processes are controlling which cells live on to become integral parts of the final brain and which cells are judged to be useless and therefore pruned. In addition to the nerve fibers, a substantial component of your brain is made up of so-called glial cells, which intermix with the neurons and are thought to provide nutrients and to regulate apoptosis and mitosis, i.e., which nerves live or die during pruning stages. In 1997, it was discovered that a factor secreted by glial cells played a critical role in facilitating the growth of synapses, which are the locales of junctions between nerve fibers. By 2001, this unknown factor had been identified as cholesterol. A decisive study showed that externally supplied cholesterol could substitute for this glial substance to produce highly efficient functioning synapses. Furthermore, if cholesterol was removed from the glial secretion, it lost its ability to stimulate synapse growth. Another critical role that cholesterol plays in your nervous system is in forming areas in your cell membrane where certain proteins important to cell signaling are anchored. In a 2004 study, it was found that these so-called lipid rafts stimulate and guide the growth of nerve axons. Cholesterol deprivation has been demonstrated to destroy the axon`s ability to grow in the proper direction. Professor Bartzokis, professor of neurology at UCLA`s David Geffen School of Medicine, has been conducting very fascinating research over the past several years on the role of myelin sheath in neurological disorders [12] . While Alzheimer`s is perhaps his main area of interest, increasingly of late he has come to believe that defective development of the myelin sheath in the nerve fibers of the developing fetus`s and/or infant`s brain could be one of the critical factors that leads to autism. He also suspects that ADHD could be caused by a disruption of brain growth during early childhood. He hypothesizes that ADHD and autistic spectrum disorder could be due to the same toxic chemical, but that the exposure occurred at different points in the child`s development. I.e., that different parts of the brain are myelinated at different times, and, depending on when the damage was done, the symptoms could manifest as either autism or ADHD. While he seems to suspect a toxin in the environment, I believe that it could be attributable to an absence rather than a presence: the absence of an adequate supply of both vitamin D and cholesterol. In an interview, Professor Bartzokis was quoted as saying: "The thicker and heavier the cells` coat, the faster and more effective their communication. Myelination, a process uniquely elaborated in humans, arguably is the most important and most vulnerable process of brain development as we mature and age." As I said before, the myelin sheath, which insulates all the nerve fibers in the nervous system, is made entirely from fat. In a series of experiments, researchers in Bartzokis` lab have demonstrated, very logically, that a thinning and breakdown in the myelin sheath can expose the nerve beneath, with the likely consequence of a multitude of neurological and behavioral problems. Without adequate insulation, cells won`t be able to communicate intact signals to one another. A recent study which measured cholesterol levels for children with autism found a striking correlation between low cholesterol and symptoms of either autism or Aspberger`s syndrome (Cholesterol Deficiency and Autism).

Brain Development in the Young Child

A human child`s brain undergoes tremendous development outside the womb: mostly from birth to two years of age. As the child experiences sensory inputs from the eyes, the ears, the skin, it sprouts a massive overgrowth of nerve fibers and connects these up at millions of synaptic junctions throughout the brain. For this growth to take place, it needs an abundant and steady supply of both cholesterol and vitamin D, which it should be getting from its mother`s milk supply, as well as its own exposure to the sun. On a good supply of fatty mother`s milk, the human baby quickly fills out with layers of fat on its thighs and upper arms. It`s almost instinctive to react to a fat baby as a healthy baby. I believe one of the biggest roles all this extra fat plays is to maintain a reserve supply of nutrients to help feed the rapidly growing brain. By the age of two the child has typically thinned out, but in the mean time this body fat has served as an excellent buffer to maintain a consistent supply of fat to nourish the explosive growth of myelin sheath throughout its brain. At around the age of two, the normal child`s brain undergoes a massive pruning stage. Through the sensory experiences it has accumulated during its first two years of life, the glial cells in its brain have been constantly making note of which fibers transmitted useful signals to which neurons at which synapses. It has been adjusting synaptic weights correspondingly, and it is now prepared to identify those nerve fibers that turned out to be counterproductive. A process of apoptosis (cell death) ensues on a magnificent scale. In studies on the brains of autistic children, it has been observed that one of the most striking anomalies is that their brains seem to be unwilling to perform the massive pruning through apoptosis at age two [13]. This could be because their brain`s glial cells don`t know which nerve fibers are unproductive. Signal transmission was unreliable throughout their first two years of life due to the poorly constructed myelin sheath. As the signal tried to travel down a pathway, noise eventually overtook it, and the distinction between productive and unproductive pathways was hopelessly blurred. To compound this problem, as we have seen, the signaling to control apoptosois depends critically on both cholesterol and vitamin D, so that, even if a glial cell was aware that it should prune a particular axon, it might not be able to execute on that plan.

What about Calcium?

Breast milk provides at least three critical nutrients to the newborn: fat, vitamin D, and calcium. Obviously, calcium is needed in rich supply for the developing bones and teeth. But calcium also plays an important role in many biochemical processes throughout the body, particularly in the immune system and the developing nervous system [14]. In the brain, communication among distant nerve cells depends on the active transport of calcium across cell membranes. Defects in calcium transport have been associated with autism spectrum disorder in several rare genetic diseases. This is one of the few areas where the search for specific genetic factors for autism has borne fruit [15] . For example, Timothy syndrome, known to be associated with calcium transport defects, causes a multitude of problems, including immune system disorders, congenital heart disease, seizures, irregular sleep patterns, small and decaying teeth, etc. It is suspected that as many as 80 percent of people with Timothy syndrome have autistic spectrum disorder. Skim milk is obviously missing the fat. The vitamin D artificially added to skim milk will be poorly absorbed due to the lack of associated fat. But what about the calcium? The good news is that calcium is water soluble, so when the fat is removed, all the calcium stays behind in the milk. The bad news is that, as for vitamin D, the lack of fat interferes with the absorption of the calcium through the gut. If you pour the milk over a bowl of bran flakes, you further reduce your ability to make use of the calcium. In a study involving 142 women [16], researchers found that those who had the highest ratio of fat to fiber in their diet were best able to utilize dietary calcium, while those who ate the least fat and the most fiber wasted a good part of their calcium intake. Of course, vitamin D deficiency itself, easily a consequence of sun avoidance, has a severe impact on calcium absorption. Promoting the absorption of calcium in the gut is the best-known biological function of vitamin D.

A Note from the Author:

I have been intrigued by autism for at least two decades. I have watched as theories for causes of autism come and go — like the Pertussin in the DPT shot and mercury in fish and infant shots. In parallel, I have been dismayed by the degree to which the American public has bought into the now widespread practices of over-aggressive protection from the sun and over-diligence in avoiding fats in the diet. I have long believed that these misguided practices are the direct cause of a host of health issues now facing America`s children, including childhood obesity, ADHD, multiple allergic reactions, and teenage adult-onset diabetes. It was only recently that I began to assemble enough facts about autism to begin to believe that I had a compelling story to tell. This essay is my attempt to put that story out on the Web, in the hopes that experts and statisticians will take action to prove or disprove this theory. Disclaimer: I am not an expert on this topic, and my research at MIT is completely unrelated.

References:

• 1 Frisch, R.E., Wyshak, G. and Vincent, L., "Delayed Menarche and Amenorrhea in Ballet Dancers," New England Journal of Medicine, Vol. 303, No. 17, 1980. • 2 Jorge Chavarro, Walter C. Willett, and Patrick J. Skerrett, The Fertility Diet, McGraw Hill, 2008. • 3 Henderson, S. T., "High carbohydrate diets and Alzheimer`s disease," Med. Hypotheses 62: 689-700, 2004. • 4 Ursula Dicke and Gerhard Roth, Intelligence Evolved, pp. 71-77 in Scientific American Mind , John Rennie, Ed. in Chief, Vol. 19, No. 4, Aug/Sept 2008. • 5 www.westonaprice.org/moderndiseases/statin.html • 6 www.cholesterol-and-health.com/Vitamin-D.html • 7 Gary Taubes, Good Calories Bad Calories:Challenging the Conventional Wisdom on Diet, Weight Control, and Disease., Alfred A. Knopf., 2007. 8 www.ajc.com/health/content/shared-auto/healthnews/bird/518293.html • 9 www.cholesterol-and-health.com/statins-For-Pregnant-Women.html • 10 www.autismtoday.com/articles/Researcher%20sees%20link.asp • 11 Rachel Burkert, John McGrath, and Darryl Eyles, "Vitamin D receptor expression in the embryonic rat brain", Neuroscience Research Communications Volume 33, Issue 1 , Pages 63 – 71 • 12 www.autismconnect.org/news.asp?section=00010001&itemtype=news&id=6066 • 13Courchesne E, Carper R, Akshoomoff N., "Evidence of brain overgrowth in the first year of life in autism," Journal of the American Medical Association, July 16, 290(3), pp. 337-44, 2003. • 14content.karger.com/ProdukteDB/produkte.asp?doi=10.1159/000095221 • 15 C.P. Turner, R. Miller, C. Smith, L. Brown, K. Blackstone,S.R. Dunham, R. Strehlow, M. Manfredi, P. Slocum, K. Iverson, M. West, S.L. Ringler, and Z.C. Berry, "Widespread Neonatal Brain Damage following Calcium Channel Blockade," Developmental Neuroscience, Vol. 29, No. 3, 2007. http://www.autismcalciumchannelopathy.com/Genetic_Factors.html • 16 Wolf, RL, Cauley, JA, Baker, CE, et al., "Factors Associated with Calcium Absorption Efficiency in Pre-and Perimenopausal Women," American Journal of Clinical Nutrition, 72: 466-471, August, 2000.

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