As if you needed another reason to quit smoking (or hopefully never start), a new study has found that smoking is a significant risk factor for developing Alzheimer’s disease (AD). Amazingly enough, the same study found that when research was affiliated with the tobacco industry, a bias seemed inherent in the findings that indicated that smoking actually protects people from AD. Meanwhile, independent research has revealed the exact opposite.

Scouring over twenty years of research and excluding tobacco related information, the authors of the study concluded that the average risk for developing AD nearly doubled for smokers. However, when considering only research linked to cigarette manufacturers, the numbers were markedly different, indicating a risk factor of less than one, thus implying that smoking might actually protect you from AD. When both sets of data were combined, they resulted in a neutral and statistically insignificant probability.

The new findings, published in the Journal of Alzheimer's Disease, are important due to the fact that previous reviews of the existing data did not control for any potential biases or conflicts of interest due to any connection to the tobacco companies in their research, which in fact accounted for 25% of the studies out there.

Affiliations with the tobacco industry were included current or past funding, payment as consultation fees or employment, and any working relationship with someone who had funding from cigarette manufacturers within 10 years of publication.

The conclusions drawn by the paper highlight the importance of knowing where your information is coming from, especially when favorable results are desired from the subjects being investigated. Then again, to many of us, it may come as no surprise.

In the end, it’s up us, the public, to practice a little common sense when sifting through all of the conflicting information. While the decision to smoke is the inalienable right of each person, it may be a bit of a stretch at this point in time for cigarette companies to make positive health claims regarding their product.

According to the Center for Disease Control and Prevention (CDC), “tobacco use is the single most preventable cause of disease, disability, and death” in this country. Nearly 9 million people come down with serious illnesses caused by smoking, and tobacco is responsible for an estimated 443,000 premature deaths.

Smoking damages nearly every organ in your body. It is the root cause of a majority of lung cancer deaths (87%), and adversely affects the heart, blood vessels, and even the eyes. Smoking increases the chances of problems during pregnancy, including sudden infant death syndrome (SIDS), and more than 126 million people in the U.S. are exposed to the harmful effects of secondhand smoke.

Even in lieu of these overwhelming statistics, nearly 43 millions Americans still choose to smoke cigarettes, resulting in large sums of money spent for their purchase, but more importantly, staggering costs in terms of health care, lost productivity, and decline in quality of life.

If you or someone you know smokes, take some time to think about these statistics. For more information, visit the website for the CDC and the American Lung Association.