References

1.  National Institutes of Health's National Center for Biotechnology Information - Genes & Disease -  http://www.ncbi.nlm.nih.gov/disease/Obesity.html

2.  The American Council on Science and Health - The Irreversible Health Effects of Cigarette Smoking -  http://www.acsh.org/publications/booklets/iesmoke.pdf

3.  BMI calculator - http://nhlbisupport.com/bmi/

4. Cigarette Smoking as a Cause of Cancer, Cancer Rates and Risks, Surveillance, Epidemiology, and End Results (SEER) Statistical Publications, National Cancer Institute - http://seer.cancer.gov/publications/raterik/risks67.html

5. Smoking: Facts and Tips for Quitting, Tobacco Control Research, National Cancer Institute - http://dccps.nci.nih.gov/TCRB/Smoking_Facts/facts.html

6. Wayne State University, Department of Biological Sciences, Toxicity - http://sun2.science.wayne.edu/~bio103/toxicity.html

7. The University of Queensland, Mayne Medical School, Department of Molecular and Cellular Pathology, Alcohol Related Pathology - http://www.som.uq.edu.au/Pathology/teaching/yearThree.html

8. National Organization on Fetal Alcohol Syndrome, What is Fetal Alcohol Syndrome? - (www.nofas.org)

9. National Institute on Drug Abuse, NIDA InfoFacts, Marijuana - http://www.nida.nih.gov/Infofax/marijuana.html

10. Kaplan, Pathology, USMLE Step 1 Preparation Book, 2002

11. Genes and Disease, National Institute of Health -  http://www.ncbi.nlm.nih.gov/books/bv.fcgi?call=bv.View..ShowSection&rid=gnd.section.232

12. American Council on Science and Health - http://www.acsh.org/publications/booklets/iesmoke.pdf

Photo credits

1. Working Out Apple: San Francisco State University Student Health Service (http://www.sfsu.edu/~shs/dpm/wellness.htm)

2. Drug-free Zone: The Public School Parent's Network (http://www.psparents.net/SubstanceAbuse.htm)

3. Lungs: PresMark Publishing Co. (http://www.presmark.com/htmlfile/pictures.htm)

4. Liver: University of Utah, Health Sciences Library (http://www-medlib.med.utah.edu/WebPath/LIVEHTML/LIVERIDX.html#1)