This method for aiding Alzheimer's detection provided by the present invention includes: determining a profile of signal peptides contained in a bodily fluid from a test subject, and comparing the signal peptide profile thus determined for the test subject with a previously-determined profile of signal peptides in a bodily fluid from a healthy subject. A difference between the signal peptide profile of the test subject and the signal peptide profile of the healthy subject at a specific molecular weight is then associated with the test subject's suffering from or developing Alzheimer's.