This research first hypothesis is that Cortisol, the hormone in charge of sugar transfusion to the bloodstream to handle stressful situations is what’s causing Alzheimer’s disease because high calibers of this hormone for protracted periods of time lead to deterioration of Secretases alpha beta and gamma, in charge of the peptide of beta amyloid within the neurons. The 2nd hypothesis is that Diabetics consumption of glucose additionally stems from wanting to deter hyper cortisol secretion. Methods: This research is a review of many studies exhibiting correlation between Alzheimer’s disease and Diabetes as well as other illnesses (Hypertension, Cushing Syndrome and Schizophrenia) with High Cortisol Levels, as well as low Vitamin B12 and Folic Acid Levels and high calibers of Homocysteine. Results: In Alzheimer’s Diseases, Diabetes, Hypertension, Schizophrenia and Cushing Syndrome, High Cortisol Levels as well as Low Folic Acid and Vitamin B12 levels are conspicuous Conclusions:This proves true the hypotheses brought in the background section regarding both AD and Diabetes to stem from Cortisol secretion and rudimentally from dealing with stress and stressful everyday lives. What these finding suggest is that a possible way of downgrading Cortisol Levels and obviating or even treating verbalized diseases is by maintaining a salubrious diet of folic acid and vitamin b12 and that deficiency of these vitamins could possibly not only cause the above diseases but additionally to be the cause of stress itself.