We have all heard the expression that beauty is only skin deep. But recent research is indicating that you may not need go any further than skin deep to determine quality of health.

Aspects related to diet, diseases impacting cognitive function and diseases of movement have been identified in the skin. Now, in addition to indicating the presence of good health, the skin may also reveal the risk for Alzheimer's disease and indications of Parkinson's disease.

The American Academy of Neurology has released preliminary information regarding a study that will be presented at their upcoming meeting in April. This study was led by Ildefonsa Rodriguez-Leyva, M.D., from Central Hospital at the University of San Luis Potosi, Mexico, and demonstrates that skin tissue taken in biopsies could detect increased levels of the abnormal proteins associated with the neurodegenerative diseases Alzheimer's and Parkinson's.

"We hypothesized that since skin has the same origin as brain tissue while in the embryo that they might also show the same abnormal proteins," Rodriguez-Leyva explained. "This new test offers a potential biomarker that may allow doctors to identify and diagnose these diseases earlier on."

The study was small, including 20 participants with Alzheimer's disease, 16 with Parkinson’s disease, 17 with dementia of other nature and 12 healthy control participants.

The research revealed that participants with Alzheimer's and Parkinson's had a particular suspect protein, tau, at a rate seven times that of healthy participants and those with dementia unrelated to either Alzheimer's or Parkinson's. Alpha-synuclein protein is strongly associated with Parkinson's disease, and those participants with Parkinson's had the protein at a rate eight times higher than the healthy participants.

An earlier study also undertaken by Rodriguez-Leyva had demonstrated a higher rate of alpha-synuclein in a group of 34 participants with Parkinson's disease, 33 with atypical movement disorder Parkinson's-like and 20 healthy control participants.

In the new study, he found that those with Parkinson's disease had a higher rate of alpha-synuclein in the skin compared to the movement disorder group. The control group had no alpha-synuclein. The conclusion was that as a minimally invasive procedure, using a biopsy of skin tissue may facilitate the accuracy of the diagnosis of Parkinson's disease.

Currently, Alzheimer's and Parkinson's cannot be conclusively diagnosed without a biopsy of brain tissue. The presumptive diagnosis based on symptoms and decreases in cognitive function is generally not made until there is considerable damage within the brain.

Having an earlier diagnosis is important. Further research is needed to determine if a simple skin biopsy will contribute to an accurate and earlier diagnosis. Beauty still remains in the eye of the beholder, but the diagnosis of serious disease should not be subjective.