Autism: A Brain Under Attack
By Dr. Scott Olson
While the number of children with autism continues to climb, the reason for this devastating disease has remained a mystery.
A central mechanism (or a theory that explains the entire disease) has been elusive, but Russell Blaylock MD, author of Excitotoxins, has recently authored scientific articles that support the notion that autism may be the result of chronic microglial activation.
What exactly is chronic microglial activation? Let’s take a look.
What is in Your Head?
If you were to ask someone what their brains are made out of, their most likely answer would be to say that their brains are made out of nerves. This, it turns out, is not true.
Saying that the brains are made up of nerves is a little like saying that the universe is full of stars (ignoring the immensity of space that surrounds those stars). The trap is obvious: Stars are bright and interesting, and we tend to focus on them because they are shiny; the rest (we assume) is just empty space.
The same has been true of our brains: Nerves only make up 10 percent of the brain, yet have commanded all our attention. While the nerves are interesting and easy to see (just like the stars), it is the other 90 percent of the brain (mostly filled with cells called glial cells) that play a vital role in the brain functioning and development.
Understanding glial cells and how they react to conditions in our environment has lead Dr. Blaylock to his unified theory of brain destruction in general, and specifically to why the brains of autistic patients don’t work well.
Glia or glial cells make up 90 percent of the brain. The term “glia,” is derived from the Greek word for glue and was coined by Rudolph Virchow, a Polish scientist, who observed the glial cells held the brain together. For many years, these glial cells were thought to be inert and non-functioning; they were simply thought to be the putty holding the whole messy tangle of nerves together in the brain.
In recent years, though, scientists have begun to sit up and notice the glial cells, and – in particular for those interested in autism – the microglial cells.
The microglial cells are a unique type of brain cell that make up 20 percent of the glial cells (or 15 percent of the entire brain mass). These microglial cells act as the immune system for the brain and this is important because when these microglial cells become chronically activated, the end result is destruction of brain cells.
Activated Microglial Cells
Normally the microglial cells are just sitting there in a passive mode, ready to protect the brain. In certain cases, though, these cells go crazy and become “activated.” When microglial cells become activated, it spells disaster for a brain, notably for developing brains.
When microglial cells become active, especially when they become chronically activated, they dump neurotoxins (or nerve toxins) into the brain. These toxins called excitotoxins (mostly glutamate and quinolinic acid) excite nerves to fire. When microglial cells continuously dump glutamate and quinolinic acid into the brain, the result – over the long term – is nerve cell death.
The blessing and problem with human brains is that they develop over a long period of time. The brain begins developing in the womb and continues largely until the child is around four years old. While this type of brain development has its advantages (it may be why we are as smart as we are), is also means that there are almost five years when childrens brains especially need to be protected from attack from excitotoxins.
The question that is probably running around in your head by now is how do you stop these excitotoxins?
To understand how to stop excitotoxins from harming the brain, you have to take a detour to a scientific lab where excitotoxins were discovered. In 1969, John Olney, a scientist, discovered that the brains of experimental animals could be destroyed by giving them monosodium glutamate or MSG during key stages in development.
There are two things you should notice about what Olney discovered. The first is that monosodium glutamate is a substance that contains the exact same chemical (glutamate, an excitotoxin) that the microglial cells secrete when they become chronically activated.
The second thing you want to notice is that MSG is a food additive.
Now you can understand that there are two ways that brains can be destroyed by excitotoxins. The first is that excitotoxins can show up in our environment (in the foods we eat, the chemicals we are exposed to, the air we breathe…) and the second is excitotoxins can be released by chronically stimulating microglial cells.
These two ways, while different, are actually closely related. Many toxins in our environment can actually stimulate the microglial cells to become “primed” or ready for activation or act directly as excitotoxins.
The toxins that tend to lead to chronic microglial activation or act as excitotoxins directly are these:
• Mercury: Mercury, a heavy metal, gets special mention because not only has it shown up in vaccines, but it is also used in dentistry, and is present in some foods (mainly fish and seafood).
• Other Heavy metals: fluoride, lead, cadmium, and aluminum and others.
• Gluten: a protein found in wheat and other grains.
• Casein: a protein found in milk products.
• Food Additives: The food additives that cause the most problems are those that contain glutamate and aspartate.
There are also some thoughts that gut dysbiosis may also lead to microglial activation. Gut dysbiosis is a general term for an imbalanced gut ecology and is often marked by an overgrowth of the yeast Candida.
What to do?
The simply answer is to protect our children’s brains for chemical and environmental insults.
• Avoid vaccinations: I know this is controversial and many people won’t agree, but there are many unknowns about the long-term health of children taking so many vaccinations. The upsurge in autism occurred somewhere in the 1990s, which coincided with an increase in the number of vaccines our children are receiving (the number of suggested vaccines increased from 10 to around 36).
You have two strategies if you don’t want to avoid vaccines altogether. The first is to wait until children are older; this allows their brains and immune systems to develop more before introducing vaccines. The other strategy is to pick-and-choose; you don’t have to have every vaccination, despite what some authorities are suggesting.
• Avoid food additives: While you might think it is easy to avoid MSG, it is not. MSG, or something like it, can be found it almost every prepared food you eat (notice I didn’t say all the food you eat, but almost every prepared food you eat). The foods with the most MSG-like food additives are soups, gravies, diet anything, including diet soft drinks, most frozen foods, sauces, salad dressing, and more. These food additives have names such as yeast extract, textured protein, soy protein extract, MSG, hydrolyzed vegetable protein, vegetable protein, sodium or calcium caseinate and more. And, yes, these food additives show up in baby food as well. If you pick up a package and it has more than four ingredients, set it down and move to the next one.
• Avoid artificial sweeteners: NutraSweet® and Equal® contain aspartate (an excitotoxin) and should be avoided. Other artificial sweeteners are just as bad for your health and the health of our children.
• Keep your house clean: It goes without saying that you should avoid as many chemicals as possible and the house is a major source of many toxic exposures. There are many natural solutions to using chemical cleaners in your home.
Most of what I have suggested is for people who want to avoid the damage done by excitotoxins and is a good preventative. If you child already has autism, then following the above suggestions are likely to help, although some damage may be irreversible. Reports on the removal of gluten and dairy from the diet are encouraging, but need more study. A gluten and dairy free diet is certainly worth a trial to determine if dietary interventions will help.
1. Millward C, Ferriter M, Calver S, Connell-Jones G. Gluten- and casein-free diets for autistic spectrum disorder. Cochrane Database Syst Rev. 2008 Apr 16;(2):CD003498.
2. Blaylock RL. A possible central mechanism in autism spectrum disorders, part 3: the role of excitotoxin food additives and the synergistic effects of other environmental toxins. Altern Ther Health Med. 2009 Mar-Apr;15(2):56-60.
3. Blaylock RL. A possible central mechanism in autism spectrum disorders, part 2: immunoexcitotoxicity. Altern Ther Health Med. 2009 Jan-Feb;15(1):60-7.
4. Blaylock RL. A possible central mechanism in autism spectrum disorders, part 1. Altern Ther Health Med. 2008 Nov-Dec;14(6):46-53.
5. Whitehouse CR, Boullata J, McCauley LA. The potential toxicity of artificial sweeteners. AAOHN J. 2008 Jun;56(6):251-9; quiz 260-1.
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