If you are drinking diet drinks, eating at restaurants, using most foods on your local market shelf, etc. you are being poisoned and that may well be the reason you have PD. And why it gets worse. From a good, understandable site at

http://en.tox.it/index.php?option=co...d=67&Itemid=73

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Excitotoxins are a group of substances, usually acidic amino acids, that react with specific receptors in the brain in such a way as to lead to destruction of certain types of neurons. Glutamate is one of the more commonly known excitotoxins, but over seventy have thus far been identified. Monosodium glutamate (MSG) is the sodium salt of glutamate. Glutamate is the physiologic excitatory neurotransmitter in the brain.

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Glutamate, as a neurotransmitter, exists in the extracellular fluid only in very, very small concentrations. When the concentration of glutamate rises above normal levels, the neurons begin to fire abnormally. At higher concentrations, the cells undergo a process of delayed cell death, called “excitotoxicity”. That is, they are excited to death

There are a large and growing number of clinicians and basic scientists who believe that excitotoxins play a critical role in the development of several neurological disorders including migraines, seizures, abnormal neural development, neuropsychiatric disorders, learning disorders in children, AIDS dementia, episodic violence, lyme borreliosis, hepatic encephalopathy, specific types of obesity, neurodegenerative diseases, such as ALS, Parkinson's disease, Alzheimer's disease, Huntington's disease, and olivopontocerebellar degeneration.

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as MSG, hydrolyzed vegetable protein, and aspartame.

The amount of these neurotoxins added to our food has increased enormously since their first introduction.

Ironically, these food additives have nothing to do with preserving food or protecting its integrity. They are all used to alter the taste of food. MSG, hydrolyzed vegetable protein, and natural flavoring are used to enhance the taste of food so as to mask disagreeable taste and magnify desired taste. Aspartame is an artificial sweetener.

Excitotoxins are present in a lot of foods, in almost all processed foods. In many cases they are being added in disguised forms, such as natural flavoring, spices, yeast extract, textured protein, soy protein extract.

We know that when subtoxic levels of excitotoxins are given to animals in divided doses, full toxicity is evident, i.e., they are synergistic.

Liquid forms of excitotoxins, as occurs in soups, gravies and diet soft drinks are more toxic because they are more rapidly absorbed and reach higher blood levels.

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.MSG and aspartame are probably not direct causes of the neurodegenerative diseases, such as Alzheimer's dementia, Parkinson's disease, or amyotrophic lateral sclerosis (ALS). They may well precipitate these disorders and certainly worsen their pathology.

Many people with a propensity for developing one of these diseases would never develop a full blown disorder had it not been for their exposure to high levels of food borne excitotoxin additives.