Researchers have stated that heavy smoking during a person middle aged years can double their risk of Alzheimer’s disease and dementia in the following decades.

A study was conducted which gathered and analyzed data from over 21,100 members which previously partook in a survey when they were in their 50s and 60s. Of these individuals, 25 percent were later diagnosed with some form of dementia is the 20 years that followed the survey. Over 1,000 of these individuals where diagnosed with Alzheimer’s disease, the most common form of dementia, which is a disease that gradually causes individuals to lose their memory, reason, and ability to function regularly.

This study showed that those who smoked more than two packs of cigarettes a day, during the time of the survey, were at a higher risk of developing Alzheimer’s disease and/or vascular dementia.

Smoking has already been proven to cause numerous types of cancers as well as heart disease. Last month a report was put together determining that the worldwide cost of coping with dementia and other similarly related disease will reach over $600 billion by the end of 2010.