The idea that your mind can be affected by your stomach sounds strange ... but we actually make it a part of our lives every day, and a study published in the American Journal of Epidemiology bears out the link. This study found that men who consumed dairy products had up to a 60% increase in the risk of developing Parkinson's disease in later life. The study followed 57,000 men for several years. Men who consumed more processed milk had the most increased risk of the disease, however raw natural milk was not found to have the same effect on the body. We explain why.

The milk that most of us drink is processed - it is rare to find somebody that squeezes it straight from an udder onto their cereal! In fact, many people find the taste of unprocessed milk distasteful, so used to homogenization and pasteurization are our tastebuds. These manufacturing processes impact the molecular structure of milk, and also the microorganism makeup of the milk. Remember that not all microorganisms are bad for you - of course, salmonella and other germs do not do any good, but here are also plenty of beneficial bacteria living in your body and in substances such as milk. The pasteurization process kills the good bacteria with the bad, and decreases digestive health.

Homogenization is another unnatural process - fat molecules are split into tiny pieces, allowing the fat to stay in suspension in the liquid, rather than rising to the top as cream, as they used to do. This process is widely suspected to be the cause of dairy's impact on the risk of developing Parkinson's disease for men.

Parkinson's disease affects people's motor skills and speech, and is usually developed later in life. It is a movement disorder and a brain disease - physical movement is slowed, and tremors often develop. Secondary symptoms may include cognitive impairment, and language problems. Some of the symptoms of Parkinson's are slowed reaction time, dementia, memory loss, sleepiness or insomnia, dizziness, impact on color discrimination and contrast sensitivity and dermatitis. Most cases of Parkinson's that are currently diagnosed are described as idiopathic - that is, they don't really known the reason why they developed. This dairy theory goes a long way towards explaining all of these idiopathic cases.

Presently, it is understood that there is often a link between Parkinson's and environmental toxins (along with a susceptibility to these toxins). These toxins can include pesticides, or any that bind to neuromelanin, or generate reactive oxygen (or free radicals). Individuals who have been exposed to pesticides also are known to have a 70% higher chance of developing Parkinson's than those who have not been exposed.

Researchers are still working on discovering the cause for this link between dairy products and Parkinson's disease. The mechanism for the increase has not yet been identified, and they are still unable to explain the fact that the figures so conclusively show that men are affected, but not women. One of the theories that is being explored is the possibility that cows that have been treated with recombinant Bovine Growth Hormone may produce milk which increases the risk of Parkinson's - homogenization may increase the effect of this chemical, which has also been linked to breast, colon and prostate cancer.